CN1161693A - Synthetic lubricating oil - Google Patents

Abstract

The present invention relates to a synthetic lubricating oil comprising cyclic ketals or cyclic acetals obtained by a reaction between one or more polyhydric alcohols having an even number of hydroxyl groups of not less than 4 and not more than 10 and one or more specific carbonyl compounds, or one or more ketals or acetals which are reactive derivatives of said carbonyl compounds; a working fluid composition for a refrigerating machine comprising a hydrofluorocarbon and a refrigeration oil containing the cyclic ketals or cyclic acetals; and novel compounds of the above cyclic acetals and a production method thereof. The present invention provides a synthetic lubricating oil which shows a good thermal stability, a good oxidation resistance, no carboxylic acid formation due to hydrolysis and a low hygroscopicity and is inexpensive as well. Also, a working fluid composition for a refrigerating machine which shows a good insulating property, favorable hygroscopicity, and no carboxylic acid formation due to hydrolysis as well as being inexpensive can be provided.

Description

Synthetic Lubricant

technical field

The present invention relates to a synthetic lubricating oil based on a cyclic ketal or cyclic acetal compound with a specific structure. In addition, it also relates to a refrigeration refrigerant composition using the synthetic lubricating oil.

Furthermore, the present invention also relates to the preparation of polar oils, organic solvents, lubricants, synthetic lubricating oils, refrigerating machine oils, etc., or as intermediates for surfactants, organic solvents, polar oils, synthetic lubricating oils, refrigerating machine oils, etc. Cyclic acetals and methods for their preparation.

Background technique

In recent years, with the extension of oil change intervals, energy saving requirements, or the high performance and miniaturization of mechanical devices, the performance required for lubricating oils has become more stringent, especially for those with excellent thermal stability and oxidation stability. Lubricants are in strong demand. In addition, the destruction of the ozone layer caused by Freon, global warming caused by carbon dioxide and methane gas, forest destruction caused by sulfur dioxide or NOx in exhaust gas, soil and lake pollution caused by chemical leakage, etc., such global environmental pollution issues have become increasingly urgent. Corresponding countermeasures are also required in terms of lubricating oil.

In order to meet the requirements of improving thermal stability and oxidation stability, ethers such as polyalkylene glycols or esters such as aliphatic diesters or hindered esters have been developed, and are used in engine oils, working fluids, grease base oils, gears oil, rolling oil, precision machinery oil, etc.

However, ethers such as polyalkylene glycols have disadvantages such as (1) high hygroscopicity and (2) insolubilization of conventionally used additives because they are too highly polar than conventionally used mineral oils. As an ether that is less polar than this polyalkylene glycol, there is an ether synthesized from an alkyl halide and a polyol described in Japanese Patent Publication No. 1-29240, but a small amount of ether remains in the resulting ether. Halogen may degrade thermal stability and oxidation stability.

In addition, esters also have the problem of being hydrolyzed to form carboxylic acid and corrode metals, or have the advantage of reducing the friction coefficient due to their excellent adsorption to metals, but conversely, they may damage oiliness improvers and extreme pressure agents. effect such a disadvantage.

Therefore, there is a need for a synthetic lubricating oil that is not too polar, has excellent thermal stability and oxidation stability, does not generate carboxylic acid due to hydrolysis, and has low hygroscopicity.

On the other hand, from the viewpoint of the global environment, in order to protect the ozone layer, the use of dichlorodifluoromethane (CFC-12) used in refrigerators and car air conditioners is restricted by law, and it was decided to ban its use at the end of 1995. Subsequently, there are also legal restrictions on the use of chlorodifluoromethane (HCFC-22) used in room air conditioners and the like. Therefore, as a substitute for such CFC-12 or HCFC-22, hydrofluorocarbons that do not deplete the ozone layer, for example, 1,1,1,2-tetrafluoroethane (HFC-134a) or difluoromethane ( HFC-32) or pentafluoroethane (HFC-125).

However, since the polarity of hydrofluorocarbons is higher than that of CFC-12 or HCFC-22, if lubricating oils such as naphthalene-based mineral oils or poly-alpha-olefins and alkylbenzenes generally used in the prior art are used as refrigerating machine oils, Then these lubricating oils have poor compatibility with hydrofluorocarbons, and two-layer separation will occur at low temperatures. If the two layers are separated, the oil backflow will worsen, and a thick oil film will be attached near the condenser or evaporator as a heat exchanger to prevent heat transfer, and it will cause important defects such as poor lubrication or foaming at start-up. Therefore, prior art refrigerating machine oils cannot be used as refrigerating machine oils for these new refrigerant atmospheres. Lubricating oils with good compatibility with hydrofluorocarbons are therefore required.

Moreover, in terms of lubricity, CFC-12 or HCFC-22 also partially decomposes to generate hydrogen chloride, and this hydrogen chloride reacts with the friction surface to form a chloride film, which has the effect of improving lubricity. However, since such an effect cannot be expected from hydrofluorocarbons that do not contain chlorine atoms, lubricating oils that are more excellent in lubricity than conventional products are required for refrigerating machine oils used together with hydrofluorocarbons.

In addition, as a refrigerating machine oil used together with hydrofluorocarbons, it must also have good thermal stability under the coexistence of hydrofluorocarbons.

Furthermore, in compression refrigerators such as refrigerators and room air conditioners, since there are organic materials used in motors such as insulating materials or enameled wires, as a working medium composed of hydrofluorocarbons and refrigerator oil, it is necessary to treat these organic materials. The material has no adverse effects and its electrical insulation must also be good.

As a refrigerating machine oil that can be used in combination with hydrofluorocarbons such as 1,1,1,2-tetrafluoroethane (HFC-134a), it is described in US Pat. Polyalkylene glycol-based compounds are disclosed in JP-14894 A (European Patent No. 377122), JP-A-2-182780 (WO90/05172) and the like.

Since polyalkylene glycols are more polar than naphthalene-based mineral oils, they have good low-temperature compatibility with HFC-134a. However, as described in the specification of US Pat. No. 4,755,316, the polyalkylene glycol compound has a problem that two-phase separation occurs instead when the temperature rises. Also, for polyalkylene glycol compounds, there are several problems in addition to this. One is the problem of poor electrical insulation. This is a very big problem, and it cannot be used in refrigerators for refrigerators or refrigerators for air conditioners in which the motor is built in the compressor. Therefore, it has been proposed that this class of compounds may be used in automotive air conditioning applications where there is no such concern. Another problem is high hygroscopicity. Moisture in the polyalkylene glycol compound deteriorates thermal stability in the coexistence of HFC-134a, or hydrolyzes organic materials such as PET films. By reducing the number of ether bonds per unit weight, electrical insulation can be improved and hygroscopicity can be reduced, but compatibility with hydrofluorocarbons is deteriorated. Therefore, ether compounds such as polyalkylene glycols cannot satisfy compatibility with hydrofluorocarbons, electrical insulating properties, and hygroscopic properties at the same time.

In order to improve the problems of such polyalkylene glycol-based compounds such as electrical insulation, hygroscopicity, etc., ester-based compounds or carbonate-based compounds have been developed. For example, as refrigerating machine oil compatible with 1,1,1,2-tetrafluoroethane (HFC-134a), there are US Patent No. 4,851,144 specification (JP-A-2-276894) or JP-A-2-158693 A mixed oil of a polyalkylene glycol compound and an ester oil is disclosed in JP-P3-505602 (WO90/12849), JP-3-128991, JP-3-128992, JP-P Ester oils are disclosed in JP-A-3-88892 and JP-A-3-179091. In addition, carbonate oils are disclosed in JP-A-2-132178, JP-A-3-149295, and European Patent No. 421,298.

The ester compound or carbonate compound has excellent compatibility with hydrofluorocarbons, and also has excellent thermal stability in the presence of hydrofluorocarbons. Compared with polyalkylene glycol compounds, the electrical insulation is extremely excellent, and the heat absorption is also quite low. However, compared with the prior art working fluid of the CFC-12-mineral oil system, the polarity of freon and oil in the hydrofluorocarbon-ester oil system or hydrofluorocarbon-carbonate oil system is increased, and it is easy to contain water. Therefore, esters are hydrolyzed to generate carboxylic acids, and the generated carboxylic acids corrode metals, causing a problem of abrasion. In addition, since carbonate oil is hydrolyzed to generate non-condensable carbon dioxide, there is also a problem of lowering refrigeration capacity.

In particular, since the refrigerant filling of room air conditioners is usually carried out on site, unlike the case of refrigerators filled in factories, it is almost impossible to prevent the ingress of moisture, making HFC-ester oil The reliability of the system or HFC-carbonate oil system in room air conditioners is a concern.

In addition, WO93/24435 A discloses polyvinyl ether compounds as polyether compounds capable of improving the electrical insulation problem of polyalkylene glycols. This polyvinyl ether compound is obtained by polymerizing and hydrogenating vinyl ether monomers, and it is disclosed that this compound has good compatibility with hydrofluorocarbons and is also good in electrical insulation. However, polyvinyl ether compounds are synthesized by a polymerization method, and the products have molecular weight distribution dispersion, so some high molecular weight substances may cause capillary clogging, and may deteriorate compatibility with hydrofluorocarbons. In addition, the post-treatment method is complicated, and unstable vinyl ether monomers are used in the raw materials, so it is difficult to say that a high yield can be achieved. Especially in the case of a low degree of polymerization (about 6 degrees of polymerization), there is a disadvantage that the yield decreases. Furthermore, vinyl ether-based monomers differ in structure, and raw materials may be difficult to obtain, resulting in high prices.

On the other hand, JP-A-4-320498 and JP-A-6-57243 describe examples of using cyclic ketals and cyclic acetals in refrigerator working fluids. The former describes the use of ketals or acetals obtained from monohydric alcohols or dihydric alcohols and ketones or aldehydes for the preparation of ester or polyalkylene glycol synthetic lubricants, and the latter contains ketal or acetal groups in the molecule esters or carbonate derivatives of glycerol, tris(hydroxymethyl)ethane, tris(hydroxymethyl)propane, pentaerythritol. The former acetals and ketals have the disadvantages of small molecular weight, boiling point, and low flash point. The latter acetals and ketals have the disadvantages of high prices due to more than two steps in preparation, and some of them are difficult to achieve. Disadvantages of high purity. In addition, the latter compounds specifically disclosed as acetals and ketals have a problem that electrical insulation cannot be sufficiently improved because they contain two or more ether bonds in the molecule.

In this way, the hydrofluorocarbon-polyalkylene glycol system developed so far has problems in hygroscopicity and electrical insulation, and the hydrofluorocarbon-ester system and hydrofluorocarbon-carbonate system have problems in hydrolysis resistance. Moreover, compared with the prior CFC-12-mineral oil system, any system has problems such as easy water content, decreased thermal stability or deterioration of organic materials, metal corrosion or wear, and cannot be used as a refrigerating machine working fluid. satisfied. In addition, polyvinyl ether compounds contain a part of high-molecular-weight compounds due to their molecular weight distribution, which has the disadvantage of lowering compatibility, and also has the disadvantage of increasing cost due to restrictions on the types of raw materials. Furthermore, all the ketals and acetals reported so far have disadvantages of low molecular weight and high price.

However, acetone is mainly used as a ketone in conventional cyclic acetals, and it is often used as a protecting group in the field of sugar or polyol synthesis. Recently, 1,3-dioxolane synthesized from formaldehyde and ethylene glycol has been marketed as an organic solvent.

On the other hand, as a cyclic acetal synthesized from sorbitol and benzaldehyde, dibenzylidene sorbitol is known as a gelling agent, while a cyclic acetal synthesized from an unsaturated aldehyde and sorbitol It is used as a polymer raw material.

In addition, cyclic acetals synthesized from sorbitol and acetone, formaldehyde, acetaldehyde or butyraldehyde are known, but cyclic acetals having longer linear or branched chains than this are unknown. Furthermore, cyclic acetals synthesized from sorbitol and isobutyraldehyde are also unknown.

In terms of the use of cyclic acetals, in addition to the above-mentioned organic solvents, solvents or additives for inks, paints, etc., gelling agents, and polymer raw materials, it is also known that they can be used as absorbents for absorption refrigerators (JP-A-59-25892), dehydrating agents for refrigerating machine oils (JP-A-4-320498, JP-A-6-57243), etc.

So far, the cyclic ketals of hexahydric alcohols such as sorbitol or mannitol have been synthesized with acetone for the protection or structural identification of some compounds, but this cyclic ketal has a high melting point and is difficult to use. For polar oils, synthetic lubricating oils or refrigeration oils that require liquid properties around room temperature. Although cyclic ketals having unsaturated bonds in the alkyl chain have a feature of relatively low melting point, they also have the disadvantage of poor stability. In addition, cyclic ketals having an aromatic ring such as a phenyl group have a characteristic of gelling, and are not suitable for uses such as polar oils, synthetic lubricating oils, or refrigerating machine oils. On the other hand, cyclic acetals synthesized using alcohols with a small number of valences such as ethylene glycol have low viscosity and are not suitable for applications such as synthetic lubricating oils and refrigerating machine oils.

invention disclosure

Therefore, the object of the present invention is to provide a synthetic lubricating oil that is excellent in thermal stability and oxidation stability, does not generate carboxylic acid due to hydrolysis, etc., has low hygroscopicity, and is inexpensive, or provides compatibility with hydrofluorocarbons, electrical insulation, It is an inexpensive composition for refrigerating machines that has excellent properties such as hygroscopicity, does not generate carboxylic acid due to hydrolysis, etc.

Furthermore, another object of the present invention is to provide novel cyclic acetals which are particularly suitable for such applications as synthetic lubricating oils or refrigerating machine oils. Still another object of the present invention is to provide a process for the preparation of such novel cyclic acetals in high yields by a simple process.

As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention noticed ether compounds having a structure that does not generate carboxylic acid or carbon dioxide, and found that ketal or acetal compounds having a specific structure have extremely high electrical insulation properties , and succeeded in making it compatible with hydrofluorocarbons, electrical insulation, and hygroscopicity, which cannot be achieved in the prior ether compounds, and finally completed the present invention.

That is, the gist of the present invention involves

式中R¹表示氢原子或1～18个碳原子的直链、支链或环状烷基，R²表示1～18个碳原子的直链、支链或环状烷基，或者R¹和R²合在一起表示2～36个碳原子的亚烷基；(1) Synthetic lubricating oil, which is characterized in that it contains more than one kind (including one kind, the same below) of more than 4 yuan to less than 10 yuan (including 4 yuan and 10 yuan, the same below), and polyhydric alcohols with an even number of yuan and A cyclic ketal or cyclic acetal obtained by ketaling or acetalizing a carbonyl compound represented by the above general formula (I) or its active derivative,

In the formula, R ¹ represents a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 18 carbon atoms, R ² represents a straight chain, branched chain or cyclic alkyl group of 1 to 18 carbon atoms, or R ¹ Together with ^R2 , it represents an alkylene group of 2 to 36 carbon atoms;

式中R³表示氢原子或1～12个碳原子直链、支链或环状烷基，R⁴表示1～12个碳原子的直链、支链或环状烷基，或者R³和R⁴合在一起表示2～13个碳原子的亚烷基，R³和R⁴的合计碳原子数是1～13个；(2) Synthetic lubricating oil, which is characterized in that it contains more than one polyhydric alcohol with an even number of 4 to 8, and one or more carbonyl compounds represented by general formula (II) or their active derivatives ketal or cyclic ketals or cyclic acetals obtained by acetalization,

In the formula, ^R3 represents a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, ^R4 represents a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, or ^R3 and R ⁴ together represent an alkylene group of 2 to 13 carbon atoms, and the total number of carbon atoms of R ³ and R ⁴ is 1 to 13;

(3) The synthetic lubricating oil described in (1) or (2) above, wherein the polyhydric alcohol does not have an ether bond;

(4) The synthetic lubricating oil described in (1) or (2) above, wherein the polyhydric alcohol has one ether bond;

(5) The synthetic lubricating oil described in (3) or (4) above, wherein the cyclic ketal or cyclic acetal contains a 1,3-dioxolane structure and/or a 1,3-dioxane structure;

(6) The synthetic lubricating oil described in any one of the above (3) to (5), characterized in that it contains a saturated aliphatic alcohol of 4 or 6, 4 to 25 carbon atoms and more than one general formula (II) Cyclic ketals or cyclic acetals obtained by ketalizing or acetalizing the carbonyl compound or its active derivatives;

式中R³表示氢原子或1～12个碳原子的直链、支链或环状烷基，R⁴表示1～12个碳原子的直链、支链或环状烷基，或者R³和R⁴合在一起表示2～13个碳原子的亚烷基，R³和R⁴的合计碳原子数是1～13个；(7) Synthetic lubricating oil, which is characterized by containing one or more cyclic ketals or cyclic acetals represented by formula (IIIa), (IIIb), (IVa) or (IVb),

In the formula, ^R3 represents a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, ^R4 represents a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, or ^R3 Together with ^R4 , it represents an alkylene group of 2 to 13 carbon atoms, and the total number of carbon atoms of ^R3 and ^R4 is 1 to 13;

(8) Synthetic lubricating oil, characterized in that it contains more than one cyclic ketal or cyclic acetal represented by formula (V) or (VI), In the formula, ^R3 represents a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, ^R4 represents a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, or ^R3 Together with ^R4 , it represents an alkylene group of 2 to 13 carbon atoms, and the total number of carbon atoms of ^R3 and ^R4 is 1 to 13;

(9) Refrigerator working medium composition, which includes refrigerator oil and hydrofluorocarbons containing the cyclic ketal or cyclic acetal described in any one of the above (2) to (8);

(10) The refrigerant composition for refrigerators described in (9) above, wherein hydrofluorocarbons and refrigerator oils are contained with hydrofluorocarbons/refrigerator oils = 50/1 to 1/20 (weight ratio);

式中R⁵表示氢原子，在这种情况下，R⁶表示3个碳原子的支链烷基，或4～21个碳原子的直链或支链烷基；或者R⁵表示1～21个碳原子的直链或支链烷基，在这种情况下，R⁶表示2～21个碳原子的直链或支链烷基；(11) Cyclic acetals represented by the following general formula (i) or (ii),

In the formula, R ⁵ represents a hydrogen atom, in this case, R ⁶ represents a branched chain alkyl group with 3 carbon atoms, or a straight chain or branched chain alkyl group with 4 to 21 carbon atoms; or R ⁵ represents 1 to 21 a straight-chain or branched-chain alkyl group of 2 to 21 carbon atoms, in which case ^R represents a straight-chain or branched-chain alkyl group of 2 to 21 carbon atoms;

(12) The cyclic acetals described in (11) above, wherein R ⁵ is a hydrogen atom and R ⁶ is a branched chain alkyl group of 3 carbon atoms or a straight chain or branched chain alkyl group of 4 to 12 carbon atoms , or R ⁵ is a straight chain or branched chain alkyl group of 1 to 12 carbon atoms and R ⁶ is a straight chain or branched chain alkyl group of 2 to 12 carbon atoms;

(13) The cyclic acetals described in (11) above, wherein R ⁵ is a hydrogen atom and R ⁶ is a branched chain alkyl group with 3 to 12 carbon atoms, or R ⁵ is a straight chain with 1 to 12 carbon atoms. Chain or branched chain alkyl and R ⁶ is a straight chain or branched chain alkyl of 2 to 12 carbon atoms;

(14) The cyclic acetals described in any one of (11) to (13) above, wherein the hexahydric alcohol residue is derived from sorbitol;

式中R⁵表示氢原子，在这种情况下，R⁶表示3个碳原子的支链烷基，或4～21个碳原子的直链或支链烷基；或者R⁵表示1～21个碳原子的直链或支链烷基，在这种情况下，R⁶表示2～21个碳原子的直链或支链烷基；(15) The preparation method of the cyclic acetals described in the above (11) represented by the general formula (i) or (ii), characterized in that the hexahydric alcohol represented by the following formula (iii) and the general formula (iv) The shown carbonyl compound or its active derivative (ketal or acetal) is reacted in the presence of an acid catalyst,

In the formula, R ⁵ represents a hydrogen atom, in this case, R ⁶ represents a branched chain alkyl group with 3 carbon atoms, or a straight chain or branched chain alkyl group with 4 to 21 carbon atoms; or R ⁵ represents 1 to 21 a straight-chain or branched-chain alkyl group of 2 to 21 carbon atoms, in which case ^R represents a straight-chain or branched-chain alkyl group of 2 to 21 carbon atoms;

(16) The production method described in (15) above, wherein the hexahydric alcohol is sorbitol.

BEST MODE FOR CARRYING OUT THE INVENTION

The present invention includes synthetic lubricating oil and refrigerant composition containing specific cyclic ketals or cyclic acetals, and novel compounds with specific structures in these cyclic ketals or cyclic acetals. In this specification, for the sake of convenience, the former is referred to as the first invention, and the latter is referred to as the second invention, and each invention will be described separately below. First, the first invention will be described.

The polyol used in the first invention is a polyhydric alcohol having 4 to 10 valences and an even number of valences. When the polyhydric alcohol has an odd number, unreacted hydroxyl groups inevitably remain to increase the viscosity, which is not preferable. Furthermore, when it is used as a working fluid of a refrigerator, if a hydroxyl group remains, the compatibility with hydrofluorocarbons deteriorates, which is not preferable. Forming an ether structure by alkylating unreacted hydroxyl groups can improve viscosity or compatibility with hydrofluorocarbons, but it is not good because the number of reaction steps increases during the production process. Moreover, it is therefore difficult to obtain high-purity products. Specifically, there are erythritol, diglycerin, arabinose, ribose, sorbitol, mannitol, galactitol, iditol, talitol, allicitol, 4,7-dioxo Heteradecane-1,2,9,10-tetraol, 5-methyl-4,7-dioxadecane-1,2,9,10-tetraol, 4,7,10-trioxa Tridecane-1,2,12,13-tetraol, 1,6-dimethoxyhexane-2,3,4,5-tetraol, 3,4-diethoxyhexane-1, Polyols such as 2,5,6-tetraol, or pentaerythritol, dimerized tri(hydroxymethyl)ethane, dimerized tri(hydroxymethyl)propane, dimerized pentaerythritol, trimerized pentaerythritol, 2,9-diethylene Base-2,9-bis(hydroxymethyl)-4,7-dioxadecane-1,10-diol, 2,12-diethyl-2,12-bis(hydroxymethyl)-5 , 8-dimethyl-4,7,10-trioxatridecane-1,13-diol and other hindered alcohols. Among them, 4,7-dioxadecane-1,2,9,10-tetraol, 5-methyl-4,7-dioxadecane-1,2,9,10-tetraol, 4 , 7,10-trioxatridecane-1,2,12,13-tetraol, 1,6-dimethoxyhexane-2,3,4,5-tetraol, 3,4-di Ethoxyhexane-1,2,5,6-tetraol, 2,9-diethyl-2,9-di(hydroxymethyl)-4,7-dioxadecane-1,10- Diol, 2,12-diethyl-2,12-bis(hydroxymethyl)-5,8-dimethyl-4,7,10-trioxatridecane-1,13-diol Some polyols with more than 2 ether linkages; are not good because they are not easily available in industry and require many steps in the preparation process, thus high cost.

The number of polyols used in the first invention is 4, 6, 8 or 10, preferably 4, 6 or 8, more preferably 4 or 6. If it is more than 10 members, the viscosity of the resulting cyclic ketal or cyclic acetal will be too high. And if it is less than 4 yuan, the molecular weight is too low, so that the boiling point and flash point are low, so it is not good.

The polyol used in the first invention has 4 to 25 carbon atoms, preferably 4 to 20 carbon atoms. If more than 25 carbon atoms, the viscosity of the resulting cyclic ketal or cyclic acetal will be too high. On the other hand, if the number of carbon atoms is less than 4, the molecular weight will be too low, so that the boiling point and flash point will be low, which is not good.

In addition, the polyhydric alcohol used in the first invention is a saturated aliphatic alcohol. If there is an unsaturated bond, it is not good because thermal stability deteriorates.

Furthermore, the polyol used in the first invention preferably does not have an ether bond in the molecule from the viewpoint of having good electrical insulation. And even if it has an ether bond, it is preferably an ether bond. If there are two or more, the electrical insulating property deteriorates, so it is not preferable when the cyclic ketal or cyclic acetal of the first invention is used for an electrical insulating oil, a refrigerant, or the like. Specific examples of polyhydric alcohols having no ether bond in the molecule are erythritol, sorbitol, mannitol, galactitol, iditol, talitol, allicitol, pentaerythritol, etc., which have an ether bond Specific examples of the polyhydric alcohol are diglycerin, dimertris(hydroxymethyl)propane, dimerized tris(hydroxymethyl)ethane, and the like.

Moreover, in the case where the cyclic ketal or cyclic acetal of the first invention is used in the refrigerator working fluid, the number of polyols is preferably 4, 6 or 8, more preferably 4 Yuan or 6 Yuan. If the number of polyols is greater than 8, the viscosity will be too high, and the compatibility with hydrofluorocarbons will deteriorate. On the other hand, if the number of polyols is less than 4, the molecular weight will be too low, resulting in low boiling point and flash point, which is not good. In addition, the number of carbon atoms is preferably from 4 to 20, more preferably from 4 to 15, particularly preferably from 4 to 10. When the number of carbon atoms exceeds 20, the compatibility with hydrofluorocarbons deteriorates, which is unfavorable. On the other hand, if the number of carbon atoms is less than 4, the molecular weight will be too low, so that the boiling point and flash point will be low, which is not good. Furthermore, when a highly symmetrical alcohol such as pentaerythritol is used, the obtained cyclic ketal or cyclic acetal has a relatively high melting point, and therefore, it is not suitable for use as a refrigerator working fluid.

The carbonyl compound used in the first invention is a ketone or an aldehyde represented by the general formula (I).

The number of carbon atoms in the ketone or aldehyde represented by the general formula (I) is 2 to 37, preferably 2 to 25, more preferably 2 to 17. When the number of carbon atoms exceeds 37, the resulting cyclic ketal or cyclic acetal has too high a viscosity, which is not preferable.

^R represents a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 18 carbon atoms, preferably a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, More preferably, it represents a hydrogen atom or a linear, branched or cyclic alkyl group of 1 to 8 carbon atoms. ^R represents a straight chain, branched or cyclic alkyl group of 1 to 18 carbon atoms, preferably a straight chain, branched or cyclic alkyl group of 1 to 12 carbon atoms, more preferably 1 A linear, branched or cyclic alkyl group of ~8 carbon atoms. Alternatively, R ¹ and R ² together represent an alkylene group having 2 to 36 carbon atoms, preferably 2 to 24 carbon atoms, more preferably 2 to 16 carbon atoms. Also, R ¹ and R ² may be the same or different.

If the number of carbon atoms in ^R1 or ^R2 exceeds 18, the viscosity of the obtained cyclic ketal or cyclic acetal will be too high, which is not preferable. Moreover, if the number of carbon atoms of the alkylene group formed by combining ^R1 and ^R2 exceeds 36, the viscosity of the obtained cyclic ketal or cyclic acetal will be too high, which is undesirable.

Specifically, examples of ketones in which R ^{and R} are alkyl include acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isopropyl ketone, methyl Butyl ketone, ethyl propyl ketone, methyl sec-butyl ketone, methyl isobutyl ketone, ethyl isopropyl ketone, methyl tert-butyl ketone, methyl amyl ketone, Ethyl butyl ketone, diisopropyl ketone, methyl isoamyl ketone, dipropyl ketone, isopropyl propyl ketone, methyl neopentyl ketone, ethyl tert-butyl ketone, Methyl hexyl ketone, ethyl amyl ketone, 6-methyl-2-heptanone, 4-methyl-3-heptanone, 2-methyl-3-heptanone, 5-methyl-3- Heptanone, methyl cyclohexyl ketone, methyl heptyl ketone, ethyl hexyl ketone, dibutyl ketone, diisobutyl ketone, methyl octyl ketone, methyl nonyl ketone, dipentyl ketone ketone, methyl decyl ketone, methyl undecyl ketone, dihexyl ketone, 5-(2',2',5'-trimethylcyclohexyl)-2-pentanone, 6,10 -Dimethyl-2-undecanone, methyl tridecyl ketone, diheptyl ketone, methyl tetradecyl ketone, dioctyl ketone, methyl pentadecyl ketone , diisooctyl ketone, methyl cetyl ketone, 6,10,14-trimethyl-2-pentadecanone, dinonyl ketone, methyl heptadecyl ketone, methyl Base octadecyl ketone, didecyl ketone, etc.

In addition, examples of ketones in which R ^and R together form an alkylene group include cyclopropanone, cyclobutanone, cyclopentanone, ^{cyclohexanone} , 2-methylcyclopentanone, and 3-methylcyclopentanone. , 2-methylcyclohexanone, 3-methylcyclohexanone, 4-methylcyclohexanone, cycloheptanone, 2,4-dimethylcyclohexanone, 2,6-dimethylcyclohexanone , cyclooctanone, 2-ethylcyclohexanone, 3-ethylcyclohexanone, 4-ethylcyclohexanone, 3,5,5-trimethylcyclohexanone, 2-tert-butylcyclohexanone, 4 - tert-butylcyclohexanone, 2-isopropyl-4-methylcyclohexanone, cyclodecanone, cyclododecanone and the like.

Furthermore, examples of aldehydes in which R1 is a hydrogen atom include acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, 2-methylbutanal, hexanal, 2-methylpentanal, 3 -Methylpentanal, 4-methylpentanal, 2-ethylbutyraldehyde, 2,3-dimethylbutyraldehyde, 3,3-dimethylbutyraldehyde, cyclopentylacetaldehyde, heptanal, 2 -Methylhexanal, 3-methylhexanal, 4-methylhexanal, 5-methylhexanal, 2-ethylpentanal, cyclohexylacetaldehyde, octanal, 2-methylheptanal, 2 -Ethylhexanal, 2-propylpentanal, 2,4,4-trimethylpentanal, nonanal, 3,5,5-trimethylhexanal, decanal, isodecanal, 3,7 -Dimethyloctylaldehyde, 2-isopropyl-5-methylhexanal, undecanal, dodecanal, tridecylaldehyde, isotridecylaldehyde, deca Hexa(alkane)aldehyde, isostear(decane)aldehyde, octadecylaldehyde, 2-methyloctadecylaldehyde, etc.

And under the situation that the cyclic ketal or cyclic acetal of the first invention is used in the base oil for refrigerator working medium, preferably the ketone or aldehyde shown in the general formula (II) in the general formula (I) .

The number of carbon atoms in the ketone or aldehyde represented by the general formula (II) is 2-25, preferably 2-17, more preferably 2-11. When the number of carbon atoms exceeds 25, the compatibility between the obtained cyclic ketal or cyclic acetal and hydrofluorocarbon deteriorates, which is unfavorable.

^R represents a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 12 carbon atoms, preferably a hydrogen atom or a straight chain, branched chain or cyclic alkyl group of 1 to 8 carbon atoms, more preferably Preferable is a hydrogen atom or a linear, branched or cyclic alkyl group of 1 to 5 carbon atoms. ^R represents a linear, branched or cyclic alkyl group of 1 to 12 carbon atoms, preferably a linear, branched or cyclic alkyl group of 1 to 8 carbon atoms, more preferably 1 to 5 straight-chain, branched-chain or cyclic alkyl groups of carbon atoms. Alternatively, R and R together represent an alkylene group of 2 to 13 carbon atoms, preferably ^an alkylene group ^of 4 to 10 carbon atoms, more preferably an alkylene group of 4 to 5 carbon atoms . The total carbon number of ^R3 and ^R4 is 1-13, preferably 1-10, more preferably 1-5.

If the number of carbon atoms of ^R3 or ^R4 exceeds 12, the compatibility of the obtained cyclic ketal or cyclic acetal with hydrofluorocarbons deteriorates, which is not favorable. In addition, if the number of carbon atoms in the alkylene group formed by combining ^R3 and ^R4 exceeds 13, the compatibility of the obtained cyclic ketal or cyclic acetal with hydrofluorocarbons will deteriorate, which is not good. Furthermore, when the total number of carbon atoms of ^R3 and ^R4 exceeds 13, the compatibility of the obtained cyclic ketal or cyclic acetal with hydrofluorocarbons deteriorates, which is unfavorable.

Furthermore, from the perspective of the compatibility of the obtained cyclic ketal or cyclic acetal with hydrofluorocarbons, the alkyl groups of R ³ and R ⁴ have a branched or cyclic structure rather than a straight chain structure, and R ³ Together with ^R4 , it is better not to form an alkylene than to form an alkylene.

The ketones represented by the general formula (I) and (II) used in the first invention can be easily passed through fatty acid high-temperature decarboxylation dimerization reaction or olefin catalytic oxidation reaction (Wacker method) or secondary alcohol oxidative dehydrogenation or cycloalkane oxidation, etc. get. In the case of the Wacker process, the resulting ketones can be separated and refined into pure products by rectification. And the aldehyde shown in the general formula (I), (II) used in the first invention can be easily reduced by Rosenmund such as fatty alcohol dehydrogenation reaction, hydroformylation reaction (oxo synthesis method) of olefin, fatty acid chloride Or fatty acid obtained directly by hydrogenation. In the case of oxo synthesis, straight-chain and branched-chain aldehydes are produced, but both can be separated and refined into pure products by rectification.

In addition, active derivatives of carbonyl compounds used in the first invention include ketals and acetals that are easily synthesized from the above-mentioned ketones and aldehydes and lower alcohols having 1 to 6 carbon atoms by acid catalysis. Specific examples of lower alcohols having 1 to 6 carbon atoms include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, amyl alcohol, isoamyl alcohol, Pentanol, 1-methylbutanol, 1,1-dimethylpropanol, 1-ethylpropanol, hexanol, isohexanol, 2-ethylbutanol, 1-methylpentanol, 1,3 -Dimethylbutanol, 1-ethylbutanol and the like.

The cyclic ketal and cyclic acetal of the first invention can be obtained as follows. The reaction of polyhydric alcohol and above-mentioned ketone is ketalization reaction, and this reaction is to carry out with acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid as catalyzer, relative to polyhydric alcohol, catalyst consumption is 0.1～10% ( mol), preferably 1.0-7.0% (mol), more preferably 1.0-5.0% (mol). This reaction does not use a solvent, or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, ligroin, petroleum ether, or a mixed solution thereof In the process, it depends on the boiling point of the ketone used, but it is carried out at a temperature of 40 to 130°C, preferably at a temperature of 60 to 100°C, and it is preferable to remove the generated water while carrying out. Depending on the case, it may be effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction will not proceed, and if it is higher than this, a side reaction of strong coloring will occur, which is also not preferable. It may be carried out under any conditions such as nitrogen flow, nitrogen atmosphere, and dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably from 5 to 200 hours. The obtained cyclic ketal can be subjected to pretreatments such as filtration and washing after neutralization, and then can be refined by operations such as clay treatment, crystallization, and evaporation.

In addition, the reaction of polyols with the above-mentioned aldehydes is an acetalization reaction. This reaction is carried out using acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, and sulfuric acid as catalysts. The amount of catalyst used is 0.01 to 5.0 % (mol), more preferably 0.1 to 2.0% (mol). This method does not use solvents, or inert solvents such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, butane, petrolatum, petroleum ether, or their mixed solvents In the process, it depends on the boiling point of the aldehyde used, but it is carried out at a temperature of 20 to 130° C., preferably at a temperature of 40 to 100° C., and it is preferable to remove generated water while carrying out. Depending on the case, it may be effective to carry out the reaction under reduced pressure. If the temperature is low, the reaction cannot proceed; and if the temperature is high, a side reaction of strong coloring occurs. In addition, it can also be performed under any conditions such as nitrogen flow, nitrogen atmosphere, and dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably 1 to 30 hours. After neutralization, the obtained cyclic acetal is subjected to pretreatments such as filtration and washing, and then can be purified by clay treatment, crystallization, distillation and other operations.

In addition, the reaction between polyols and active derivatives of ketones such as ketals is a transketalization reaction (transketalization), which is carried out using acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, and sulfuric acid as catalysts. Specifically, the amount of catalyst used is 0.1-10% (mol), preferably 1.0-7.0% (mol), more preferably 1.0-5.0% (mol). This reaction does not need a solvent, or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, petroleum petroleum, petroleum ether, or in a mixed solvent, because The ketal to be used depends on the boiling point of the lower alcohol to be produced, but it is carried out at a temperature of 40 to 150°C, preferably 70 to 130°C, and the lower alcohol to be produced is preferably removed during the process. Depending on the case, it may be effective to carry out the reaction under reduced pressure. If the temperature is lower than this, the reaction cannot proceed, and if it is higher than this, a side reaction of strong coloring will occur, which is not preferable. In addition, it can also be performed under any conditions such as nitrogen flow, nitrogen atmosphere, and dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably from 5 to 200 hours. After neutralization, the obtained cyclic ketal is subjected to pretreatments such as filtration and washing, and then can be purified by clay treatment, crystallization, distillation and other operations.

In addition, the reaction between polyol and active derivative acetal of aldehyde is a transacetalization reaction (transacetalization), which is carried out with acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid, etc. Specifically, the amount of catalyst used is 0.01-5.0% (mol), preferably 0.1-2.0% (mol). This method does not use solvents, or inert solvents such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, butane, petrolatum, petroleum ether, or their mixed solvents In this process, depending on the boiling point of the acetal used and the lower alcohol produced, it is carried out at a temperature of 20 to 150° C., preferably 50 to 130° C., and it is preferred to remove the lower alcohol produced while carrying out the process. Depending on the case, it may be effective to carry out the reaction under reduced pressure. If the temperature is low, the reaction cannot proceed, and if the temperature is high, side reactions such as intense coloring will occur. In addition, it can also be performed under any conditions such as nitrogen flow, nitrogen atmosphere, and dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably 1 to 30 hours. After neutralization, the obtained cyclic acetal is subjected to pretreatments such as filtration and washing, and then can be purified by clay treatment, crystallization, distillation and other operations.

The ratio of ketone or active derivative ketal of ketone or aldehyde or active derivative acetal of aldehyde (hereinafter referred to as carbonyl compound) reacted with polyol is per 1 mole of polyol A/2 mole of carbonyl compound (A is polyol arity). In order to increase the reaction rate, it is also possible to react with a molar excess of carbonyl compound than A/2, and then remove the excess carbonyl compound after the reaction.

The cyclic ketal or cyclic acetal of the first invention can be obtained by reacting one or more polyhydric alcohols with one or more ketones or active derivatives of ketones or acetals of aldehydes or active derivatives of aldehydes . In addition, cyclic ketals or cyclic acetals obtained individually may be used in combination. For example, cyclic ketal obtained from 1 mole of sorbitol and 3 moles of methyl ethyl ketone (viscosity 63.1 mm ² /s at 40°C) and cyclic ketal obtained from 1 mole of diglycerol and 2 moles of methyl ethyl ketone Cyclic ketals (viscosity at 40°C: 7.69 mm ² /s) can be synthesized separately, and then the two can be mixed to adjust to a desired viscosity. As a specific example, 1 mole of cyclic ketal obtained from 1 mole of sorbitol and 3 moles of methyl ethyl ketone and 1 mole of cyclic ketal obtained from 1 mole of diglycerol and 2 moles of methyl ethyl ketone Mixed, you can get VG22 lubricating oil. Alternatively, the above mixture can be obtained by reacting 1 mol of sorbitol and 1 mol of diglycerin with 5 mol of methyl ethyl ketone. In addition, reacting 1 mole of sorbitol with two ketones or aldehydes, such as 2 moles of 3,5,5-trimethylhexanal and 1 mole of methyl ethyl ketone, can also obtain the cyclic condensation compound of the first invention. Ketones or cyclic acetals.

And, the unreacted hydroxyl group that exists in the obtained cyclic ketal, cyclic acetal is better as little as possible, such unreacted hydroxyl group counts on average, with respect to the hydroxyl number of raw material polyhydric alcohol, will be in 20 % or less, preferably less than 10%, more preferably less than 5%, especially preferably less than 3%. If more than 20% of unreacted hydroxyl groups remain, the viscosity will be too high and the boiling point or flash point will be too low, which is not preferable. In the case where such cyclic ketals or cyclic acetals are used in the base oil of refrigerator working fluids, the less unreacted hydroxyl groups, the better, should be less than 10%, preferably less than 5%, and more It is preferably at most 3%, especially preferably at most 2%, most preferably at most 1%. If more than 10% of unreacted hydroxyl groups remain, the compatibility with hydrofluorocarbons and electrical insulation will deteriorate, which is undesirable.

In addition, when the cyclic ketal or cyclic acetal of the first invention is used in an electrical insulating oil or a base oil of a refrigerating machine, polyhydric alcohols having no ether bond structure have higher electrical insulating properties. , so it is better. Therefore, cyclic ketals or cyclic acetals obtained from hexahydric alcohols such as sorbitol, mannitol, galactitol, iditol, talitol, and allicitol, or polyhydric alcohols such as erythritol , which is better than cyclic ketals or cyclic acetals obtained from alcohols such as diglycerol or dimerized tri(hydroxymethyl)propane, etc., which have one ether bond.

Furthermore, when the cyclic ketal or cyclic acetal of the first invention is used in an electrical insulating oil or a base oil of a refrigerant, it contains a 1,3-dioxolane structure and/or a 1,3 - Those with a dioxane structure are preferable because they have high electrical insulation properties. Furthermore, those containing a 1,3-dioxolane structure are particularly preferable. Therefore, alcohols having a hydroxyl group in the ortho position, such as erythritol, diglycerin, sorbitol, mannitol, galactitol, iditol, talitol, and allicitol, are preferably used. Moreover, in the case of using hexavalent alcohols such as sorbitol, mannitol, galactitol, iditol, talitol, allicitol, etc., the cyclic contractions represented by formula IIIa and formula IIIb can be obtained. Ketones or cyclic acetals, but the compound of formula IIIa having three 1,3-dioxolane structures is preferred because of its high electrical insulation. And under the situation of using erythritol, can obtain the cyclic ketal or cyclic acetal shown in formula IVa or formula IVb, but have two 1, the formula IVa compound of 3-dioxolane structure because of its electron High insulation and better. If sorbitol, mannitol, galactitol, iditol, talitol, allicitol and other hexavalent alcohols or erythritol react with ketones or ketals, it is easy to generate formula IIIa, formula IVa Cyclic ketals, and if they react with aldehydes or acetals, it is easy to generate cyclic acetals of formula IIIb and formula IVb. Therefore, for these alcohols, it is preferred to use ketones or ketals for the reaction.

Furthermore, in the case where the cyclic ketal or cyclic acetal of the first invention is used in the base oil of the refrigerator working fluid, among those whose valency is an even number of polyhydric alcohols, the formula (III) represents the six-element Cyclic ketals or cyclic acetals obtained from alcohols, or cyclic acetals obtained from tetrahydric alcohols such as erythritol, diglycerin, and dimerized tri(hydroxymethyl)propane shown in formulas (IV) to (VI). Ketals and cyclic acetals are particularly preferable from the standpoint of a balance of various physical properties such as compatibility with hydrofluorocarbons, electrical insulation, melting point, and viscosity. The cyclic ketals obtained from well-symmetrical pentaerythritol represented by the formula (VIIa) or the formula (VIIb) are unfavorable even if they are also tetrahydric alcohols because they are solid at room temperature. Among the compounds represented by formulas (III) to (VI), compounds represented by (IIIa), (IIIb), (IVa), and (V) with 1,3-dioxolane structure are preferred, wherein Especially the compounds shown by (IIIa), (IVa) and (V) having only 1,3-dioxolane structure are good, and among them, (IIIa) and ( Compound shown in IVa).

第一发明中使用的环状缩酮或环状缩醛，其100℃的粘度较好在1mm²/s以上～100mm²/s以下，更好的是在1mm²/s以上～50mm²/s以下，尤其好的是在1mm²/s以上～30mm²/s以下。The melting point of the cyclic ketal or cyclic acetal of the first invention is preferably at most 10°C, more preferably at most -10°C, particularly preferably at most -30°C. Although cyclic ketals or cyclic acetals with a melting point exceeding 10°C like (VIIa) and (VIIb) are not good when used alone as lubricating oils, they can be combined with other cyclic ketals or cyclic acetals of the first invention with low melting points. Cyclic acetals or other lubricating oils are mixed and used in limited amounts.

The cyclic ketal or cyclic acetal used in the first invention preferably has a viscosity at 100°C of not less than 1 mm ² /s and not more than 100 mm 2 /s, more preferably not less than 1 ^{mm 2 /} s and not more than 50 mm ^{2 /} s. s or less, particularly preferably 1 mm ² /s or more to 30 mm ² /s or less.

In addition, when the cyclic ketal or cyclic acetal used in the first invention is used in the base oil of the refrigerator working fluid, the lower the two-phase separation temperature with the hydrofluorocarbon, the better, preferably at 10°C below, preferably below 0°C, more preferably below -10°C, especially preferably below -30°C.

The cyclic ketal or cyclic acetal of the first invention can be mixed with other lubricating oils. As other lubricating oils, mineral oils or hydrocarbon synthetic oils such as polybutene, poly-α-olefins, and alkylbenzenes, aliphatic diesters or neopentyl polyol esters, polyalkylene glycols, polyphenylene glycols, etc. Ether, carbonate, phosphate, silicate, silicone oil, perfluoropolyether, etc. For specific examples, please refer to the new edition of "Physical Chemistry of Lubrication" (Xingshufang) or "Basic and Application of Lubricating Oil" (Corona Company), etc. .

The mixing ratio of the cyclic ketal or cyclic acetal of the first invention and other lubricating oils, ideally the content of the cyclic ketal or cyclic acetal in the mixed lubricating oil is more than 0.1% (by weight), preferably in 1.0% by weight or more, more preferably 5.0% by weight or more, particularly preferably 10% by weight or more. If the content is less than 0.1% by weight, the effect of improving lubricity or the effect of preventing hydrolysis of esters, carbonates, etc. cannot be sufficiently exerted. Moreover, when the cyclic ketal or cyclic acetal of the first invention is used in the base oil of the refrigerator working fluid, the other lubricating oil to be mixed is preferably one with excellent compatibility with hydrofluorocarbons, preferably Among them are neopentyl polyol esters or polyalkylene glycols, carbonates, and the like. However, in the case where the compatibility between the cyclic ketal or cyclic acetal of the first invention and hydrofluorocarbons is very excellent, it is also possible to combine the cyclic ketal or cyclic acetal such as at the two-phase separation temperature within the range where the two-phase separation temperature does not exceed 10°C. At -30°C or lower, preferably at -50°C or lower, it is mixed with lubricating oil with poor compatibility with hydrofluorocarbons, such as alkylbenzene or mineral oil.

The cyclic ketal or cyclic acetal of the first invention has excellent compatibility with hydrofluorocarbons and excellent electrical insulation properties, so it can be used as a mixture with hydrofluorocarbons as a working fluid for refrigerators. Furthermore, since it is excellent in electrical insulation, it can be used for electrical insulating oil. In addition, due to the ring structure in the molecule, it can be used in traction oils. Furthermore, since it is excellent in lubricity and heat resistance, it can be used for an engine oil, a turbine oil, a gear oil, a hydraulic oil, a bearing oil, a metal processing oil, a compressor oil, a grease base oil, etc. Furthermore, since it has excellent lubricity, it can be used as an additive for low-sulfur gas oil. Moreover, since there are many oxygen atoms in the molecule, it can also be used as a fuel oil additive such as an octane value booster.

In the case that the cyclic ketal or cyclic acetal of the first invention is used in the refrigerator working fluid, the hydrofluorocarbon in the refrigerator working fluid composition of the present invention and the cyclic ketal or cyclic acetal used in the present invention The mixing ratio of the cyclic acetal refrigerating machine oil is usually hydrofluorocarbon/refrigerating machine oil = 50/1 to 1/20 (weight ratio), preferably 10/1 to 1/5 (weight ratio). If the ratio of hydrofluorocarbon is higher than hydrofluorocarbon/refrigerating machine oil = 50/1, the viscosity of the hydrofluorocarbon-refrigerating machine oil mixed solution may decrease, which may deteriorate the lubricity, which is not preferable. On the other hand, if the ratio of hydrofluorocarbon is lower than hydrofluorocarbon/refrigerating machine oil = 1/20, the refrigerating capacity may be insufficient, which is also not preferable.

The hydrofluorocarbons that can be used in the first invention refer to difluoromethane (HFC-32), 1,1-difluoroethane (HFC-152a), 1,1,1-trifluoroethane (HFC-143a ), 1,1,1,2-tetrafluoroethane (HFC-134a), 1,1,2,2-tetrafluoroethane (HFC-134), pentafluoroethane (HFC-125), etc., especially Preferred are 1,1,1,2-tetrafluoroethane, difluoromethane, pentafluoroethane, 1,1,1-trifluoroethane. These hydrofluorocarbons may be used alone, or two or more hydrofluorocarbons may be used in combination.

To the cyclic ketal or cyclic acetal of the first invention, commonly used antioxidants, extreme pressure agents, oiliness improvers, defoamers, detergent dispersants, viscosity index improvers, antioxidants, etc. Rust agent, anti-emulsifier and other lubricating oil additives. For example, 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-cresol, 4,4'-methylenebis(2,6-di tert-butylphenol) and other phenolic antioxidants, or P, P-dioctylphenylamine, one-octyldiphenylamine, phenothiazine, 3,7-dioctylphenothiazine, phenyl- Amine antioxidants such as 1-naphthylamine, phenyl-2-naphthylamine, alkylphenyl-1-naphthylamine, alkylphenyl-2-naphthylamine, or alkyl disulfide, thiodipropylene Sulfur antioxidants such as acid esters and benzothiazoles, or zinc dialkyldithiophosphates, zinc diaryldithiophosphates, etc. The added amount thereof is 0.05 to 2.0% by weight relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the first invention.

Zinc compounds that can be used as extreme pressure agents and oiliness improvers, such as zinc dialkyldithiophosphate, zinc diaryldithiophosphate, etc., or thiodipropionate, dialkylsulfide, Sulfur compounds such as benzyl sulfide, dialkyl polysulfide, alkyl mercaptan, dibenzothiophene, 2,2'-dithiobis(benzothiazole), triaryl phosphate or triaryl phosphite, Phosphorus compounds such as trialkyl phosphate or trialkyl phosphate, chlorine compounds such as chlorinated paraffin, molybdenum compounds such as molybdenum dithiocarbamate, molybdenum dithiophosphate, molybdenum disulfide, perfluoroalkyl polyether, trifluoro Fluorine compounds such as vinyl chloride polymers and fluorinated graphite, silicon compounds such as fatty acid-modified polysiloxane, graphite, etc. The added amount thereof is 0.05 to 10% by weight relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the first invention.

Silicone oils such as dimethylpolysiloxane or organic silicates such as diethyl silicate can be used as the defoaming agent. The added amount thereof is 0.0005 to 1% by weight relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the first invention.

Usable as detergent dispersants include sulfonates, phenates, salicylates, phosphates, polybutenyl succinimides, polybutenyl succinates, and the like. The added amount thereof is 0.05 to 10% by weight relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the first invention.

In the case where the cyclic ketal or cyclic acetal of the first invention is used in the refrigerator working fluid, as an additive, benzotriazole and/or benzotriazole derivatives for protecting the metal surface can be added, Triaryl phosphate and/or triaryl phosphite can also be added to improve lubricity, and phenolic compounds with the ability to capture free radicals or metal deactivators with chelating ability can also be added to improve thermal stability wait.

The triaryl phosphate or triaryl phosphite usable in the first invention has 18 to 70 carbon atoms, more preferably 18 to 50 carbon atoms. Specifically, triphenyl phosphate, tris(hydroxyphenyl) phosphate, tris(xylyl) phosphate, (hydroxyphenyl)-diphenyl phosphate, (xylyl)-diphenyl phosphate, phosphoric acid Tris(tribromophenyl), tris(dibromophenyl)phosphate, tris(2,4-di-tert-butylphenyl)phosphate, tris(nonylphenyl)phosphate and other triaryl phosphates, or triphenylphosphite Ester, tris (hydroxyphenyl) phosphite, tris (xylyl) phosphite, (hydroxyphenyl) diphenyl phosphite, (xylyl) diphenyl phosphite, tris (2, 4-tert-butylphenyl), tris (nonylphenyl) phosphite, tris (tribromophenyl) phosphite, tris (dibromophenyl) phosphite and other triaryl phosphites, preferably triaryl phosphate Phenyl ester, tris (hydroxyphenyl) phosphate, tris (xylyl) phosphate, tris (2,4-di-tert-butylphenyl) phosphate, triphenyl phosphite, tris (hydroxyphenyl) phosphite, Tris(xylyl) phosphate, tris(2,4-di-tert-butylphenyl) phosphite. The added amount of triaryl phosphate and/or triaryl phosphite is usually 0.1 to 5.0% by weight relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the first invention. Preferably it is 0.5 to 2.0% by weight.

The amount of benzotriazole and/or benzotriazole derivatives that can be used in the first invention is usually 0.001 to 0.1% relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the present invention (weight), preferably 0.003 to 0.03% (weight). Furthermore, the benzotriazoles and benzotriazole derivatives usable in the present invention have 6 to 50 carbon atoms, preferably 6 to 30 carbon atoms. Specifically, benzotriazole, 5-methyl-1H benzotriazole, 1-(dioctylaminomethyl)benzotriazole, 1-(dioctylaminomethyl)-5- Tolylbenzotriazole, 2-(5′-methyl-2′-hydroxyphenyl)benzotriazole, 2-[2′-hydroxy-3′,5′-bis(α,α-dimethyl benzyl)phenyl]-2H-benzotriazole, 2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole, 2-(3′-tert-butyl -5'-methyl-2'-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)-5-chlorobenzo Triazole, 2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole, 2-(5′-tert-butyl-2′-hydroxyphenyl)benzotriazole , 2-(2'-hydroxy-5'-methylphenyl) benzotriazole, 2-(2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2-[2'- Hydroxy-3′-(3″, 4″, 5″, 6″-tetrahydrophthalimidomethyl)-5′-methylphenyl]benzotriazole, etc., preferably Benzotriazole, 5-methyl-1H-benzotriazole, etc.

The amount of the metal deactivator that can be used in the first invention is usually 0.001 to 2.0% by weight, preferably 0.003% with respect to the lubricating oil containing the cyclic ketal or cyclic acetal of the present invention. ~0.5% by weight. The metal passivating agent that can be used in the present invention preferably has chelating ability and has 5 to 50 carbon atoms, preferably 5 to 20 carbon atoms. Specifically, N, N'-disalicylidene-1,2-diaminoethane, N,N'-disalicylidene-1,2-diaminopropane, N-salicylidene Base-N'-dimethyl-1,2-diaminoethane, N,N'-disalicylidene hydrazine, N,N'-bis(α,5-dimethylsalicylidene)- 1,2-diaminoethane, N,N'-bis(α,5-dimethylsalicylidene)-1,3-propanediamine, N,N'-bis(α,5-dimethyl Dimethylsalicylidene)-1,6-hexanediamine, N,N'-bis(α,5-dimethylsalicylidene)-1,10-decanediamine, N,N'-bis( α,5-Dimethylsalicylidene)ethylenetetramine, salicylaldoxime, 2-hydroxy-5-methylacetophenoxime, acetylacetone, ethyl acetoacetate, 2-ethylhexyl acetoacetate , dimethyl malonate, diethyl malonate, 2-ethylhexyl malonate, anthranilic acid, nitrilotriacetic acid, dihydroxyethylglycine, hydroxyethylethylenediaminetriacetic acid, Hydroxyethyliminodiacetic acid, ethylenediamine, 3-mercapto-1,2-propanediol, alizarin, quinizarin, mercaptobenzothiazole, etc., preferably N, N'-disalicylidene- 1,2-diaminoethane, N,N'-disalicylidene-1,2-diaminopropane, acetylacetone, ethyl acetoacetate, alizarin, quinarizarin, etc.

The amount of the phenolic compound capable of trapping radicals that can be used in the first invention is usually 0.05 to 2.0% by weight relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the present invention , preferably 0.05 to 0.5% by weight. The phenolic compounds usable in the present invention have 6 to 100 carbon atoms, preferably 10 to 80 carbon atoms. Specifically, 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, 4,4'-methylenebis(2,6-di-tert-butylphenol ), 4',4-butylidene bis(3-methyl-6-tert-butylphenol), 2,2-methylenebis(4-ethyl-6-tert-butylphenol), 2,2 '-Methylenebis(4-methyl-6-tert-butylphenol), 4,4'-isopropylidene diphenol, 2,4-dimethyl-6-tert-butylphenol, tetrakis[ Methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butyl Phenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 2,2′-dihydroxy-3 , 3′-bis(α-methylcyclohexyl)-5,5′-dimethyl-diphenylmethane, 2,2′-isobutylene bis(4,6-dimethylphenol), Ethylene glycol bis[3,3-bis(4′-hydroxy-3′-tert-butylphenyl)butyrate, 2,6-bis(2′-hydroxy-3′-tert-butyl-5′- Methylbenzyl)-4-methylphenol, 1,1'-bis(4-hydroxyphenyl)cyclohexane, 2,5-di-tert-amylhydroquinone, 2,5-di-tert-butylhydroquinone, 1 , 4-dihydroxyanthraquinone, 3-tert-butyl-4-hydroxyanisole, 2,4-dibenzoyl resorcinol, 4-tert-butyl catechol, 2,6-di-tert-butyl -4-ethylphenol, 2-hydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,4 , 5-trihydroxybenzophenone, α-tocopherol, bis[2-(2-hydroxy-5-methyl-3-tert-butylbenzyl)-4-methyl-6-tert-butyl terephthalate phenyl ester], triethylene glycol bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol bis[3-(3,5 -di-tert-butyl-4-hydroxyphenol)propionate], 3,9-bis[2-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1, 1-Dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane, etc., preferably 2,6-di-tert-butylphenol, 2,6-di-tert-butyl Base-4-methylphenol, 4,4'-methylene bis(2,6-di-tert-butylphenol), 4,4'-methylene bis(3-methyl-6-tert-butylphenol ), 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 4, 4′-isopropylidene diphenol, 2,4-dimethyl-6-tert-butylphenol, tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,3,5-trimethyl-2,4,6- Tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 2,6-di-tert-butyl-4-ethylphenol, 2,6-bis(2′-hydroxy-3′-tert-butyl Base-5′-methylbenzyl)-4-methylphenol, terephthalic acid bis[2-(2-hydroxy-5-methyl-3-tert-butylbenzyl)-4-methyl-6 -tert-butylphenyl ester], triethylene glycol bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate, 1,6-hexanediol bis[3-(3 , 5-di-tert-butyl-4-hydroxyphenyl) propionate] and so on.

In addition, additives capable of stabilizing Freon refrigerants, such as organotin compounds and boron compounds, may also be added. The added amount thereof is 0.001 to 10% by weight relative to the lubricating oil containing the cyclic ketal or cyclic acetal of the first invention.

The second invention will be described below.

式中R⁵表示氢原子，在这种情况下，R⁶表示3个碳原子的支链烷基或4～21个碳原子的直链或支链烷基；或者R⁵表示1～21个碳原子的直链或支链烷基，在这种情况下，R⁶表示2～21个碳原子的直链或支链烷基。Among the cyclic ketals and cyclic acetals of the first invention, the compounds shown in formula (IIIa) and formula (IIIb) are novel compounds, and the cyclic acetals (general formula (i) or the compound shown in (ii)) is described as the second invention. In the second invention, the cyclic ketals and cyclic acetals described in the first invention are collectively referred to as "cyclic acetals".

In the formula, R ⁵ represents a hydrogen atom, in this case, R ⁶ represents a branched chain alkyl group of 3 carbon atoms or a straight chain or branched chain alkyl group of 4 to 21 carbon atoms; or R ⁵ represents 1 to 21 A straight-chain or branched-chain alkyl group of carbon atoms, in this case, ^R6 represents a straight-chain or branched-chain alkyl group of 2 to 21 carbon atoms.

Among the compounds represented by the general formula (i) or (ii), specific examples of the hexahydric alcohol capable of giving a hexahydric alcohol residue include the following hexahydric alcohols. That is, hexitols obtained by reduction with hexoses, such as sorbitol, mannitol, galactitol, iditol, talitol, allicitol and the like.

Among them, sorbitol is the most preferable from the viewpoint of availability or price.

In the general formula (i) or (ii), when R ⁵ is a hydrogen atom, R ⁶ is a branched chain alkyl group with 3 carbon atoms, or a branched chain or branched chain alkyl group with 4 to 21 carbon atoms, It is preferably a branched chain saturated alkyl group of 3 carbon atoms or a straight chain or branched chain saturated alkyl group of 4 to 12 carbon atoms, more preferably a branched chain saturated alkyl group of 3 to 12 carbon atoms.

The branched chain alkyl group having 3 carbon atoms represented by R ⁶ specifically refers to an isopropyl group.

On the other hand, examples of the linear or branched alkyl group having 4 to 21 carbon atoms specifically include the following.

That is, examples of straight-chain alkyl groups include butyl, pentyl, hexyl, heptyl, octyl, nonyl, undecyl, tridecyl, pentadecyl, heptadecyl, and nonadecyl. base, twenty-one alkyl group, etc.

Examples of the α-methyl branched alkyl group include 1-methylpropyl, 1-methylbutyl, 1-methylpentyl, 1-methylhexyl, 1-methylheptyl, 1-methyl octyl, 1-methylnonyl, 1-methyldecyl, 1-methylundecyl, 1-methyloctadecyl and the like.

Examples of the α-branched alkyl group include 1-ethylpropyl, 1-ethylbutyl, 1-ethylpentyl, 1-propylbutyl, 1-ethylhexyl, 1-propylpentyl Base, 1-ethylheptyl, 1-propylhexyl, 1-butylpentyl, 1-pentylhexyl, 1-hexylheptyl, 1-octylnonyl, 1-hexylundecyl, 1-decyl Undecyl, etc.

Examples of α-multi-branched alkyl groups having α-branches and one or more branches other than α-branches include 1,2-dimethylpropyl, 1,2-dimethylbutyl, 1,3-Dimethylbutyl, 1-ethyl-2-methylpropyl, diisopropylmethyl, 1,4-dimethylpentyl, 1-isopropylbutyl, 1,3 , 3-trimethylbutyl, 1,5-dimethylhexyl, 1-ethyl-2-methylpentyl, 1-butyl-2-methylpropyl, 1-ethyl-3-methyl Amylpentyl, diisobutylmethyl, 1,5,9-trimethyldecyl, etc.

Examples of β-branched alkyl groups include 2-methylpropyl, 2-methylbutyl, 2-methylpentyl, 2-ethylbutyl, 2-methylhexyl, and 2-ethylpentyl , 2-methylheptyl, 2-ethylhexyl, 2-propylpentyl, etc.

As β-multi-branched alkyl groups having β-branches and one or more branches other than α-branches and β-branches, 2,3-dimethylbutyl, 2,4,4 -trimethylpentyl, 2-isopropyl-5-methylhexyl and the like.

As other branched alkyl groups having one or more branches other than α-branch and β-branch, 3-methylbutyl, 3-methylpentyl, 4-methylpentyl, 3-methylpentyl, 3 , 3-dimethylbutyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 3,5,5-trimethylhexyl, isodecyl, 3,7-dimethyloctyl base, isohetadecyl, etc.

Examples of alkyl groups that do not have a hydrogen atom at the α-position and have a tertiary carbon atom at the α-position include 1,1-dimethylethyl, 1-methylcyclopropyl, 1,1-dimethyl Propyl, 1-methylcyclobutyl, 1,1-dimethylbutyl, 1,1,2-trimethylpropyl, 1-methylcyclopentyl, 1,1-dimethylpentyl , 1-methyl-1-ethylbutyl, 1,1-diethylpropyl, 1,1-diethylbutyl, etc.

As an alkyl group that does not have a hydrogen atom at the β-position and has a tertiary carbon atom at the β-position, 2,2-dimethylpropyl, 2,2-dimethylbutyl, 1,2,2 - Trimethylpropyl, 1-ethyl-2,2-dimethylpropyl, 2,2-dimethylpentyl, 2,3-dimethyl-2-isopropylbutyl and the like.

As an alkyl group that does not have a hydrogen atom in the α-position and β-position and has a tertiary carbon atom in the α-position and β-position, 1,1,2,2-tetramethylpropyl, 1 , 1,2,2-tetramethylbutyl, 1,1,2,2-tetramethylhexyl, etc.

In addition, in the general formula (i) or (ii), in the case where ^R is a linear or branched alkyl group of 1 to 21 carbon atoms, ^R is a linear or branched alkyl group of 2 to 21 carbon atoms. Alkanes. More preferably, ^R is a linear or branched saturated alkyl group of 1 to 12 carbon atoms, and in this case, R is ^preferably a linear or branched saturated alkyl group of 2 to 12 carbon atoms. alkyl.

In the above case, as a straight chain or branched chain alkyl group of 1 to 21 carbon atoms represented by ^R , specifically, in addition to the specific exception of the above straight chain or branched chain alkyl group of 4 to 21 carbon atoms, Examples thereof include methyl, ethyl, propyl, and isopropyl.

Therefore, as a straight chain or branched chain alkyl group of 2 to 21 carbon atoms represented by R ⁶ , specifically, in addition to the specific exceptions of the above straight chain or branched chain alkyl group of 4 to 21 carbon atoms, ethyl can also be enumerated. , Propyl, Isopropyl.

As the cyclic acetals represented by the above general formula (i) or (ii), the following specific examples (compound names and structural formulas) can be cited, but are not limited thereto.

(1) 1.2:3.4:5.6-Tris-O-(2-methylmethylenepropylene)sorbitol

(2) 1.3:2.4:5.6-Tris-O-(2-methylidenepropylene)sorbitol

(3) 1.2:3.4:5.6-tri-O-(3,5,5-trimethylhexylidene)sorbitol

(4) 1.3:2.4:5.6-tri-O-(3,5,5-trimethylhexylidene)sorbitol

(5) 1.2:3.4:5.6-tri-O-(1-methylidenepropylene)sorbitol

(6) 1.3:2.4:5.6-tri-O-(1-methylidenepropylene)sorbitol

(7) 1.2:3.4:5.6-Tris-O-(1,3-dimethylbutylene)sorbitol

(8) 1.3:2.4:5.6-tri-O-(1,3-dimethylbutylene)sorbitol

(9) 1.2:3.4:5.6-tri-O-(hexamethylene)sorbitol

(10) 1.3:2.4:5.6-tri-O-(hexamethylene)sorbitol

(11) 1.2:3.4:5.6-tri-O-(partial isostearylidene)sorbitol

(12) 1.3:2.4:5.6-tri-O-(partial isostearylidene)sorbitol

(13) 1.2:3.4:5.6-Tri-O-(2-ethylhexylidene)sorbitol

(14) 1.3:2.4:5.6-Tris-O-(2-ethylhexylidene)sorbitol

(15)1.2:3.4:5.6-Tris-O-(1-heptadecyl octadecylene)sorbitol

(16) 1.3:2.4:5.6-Tris-O-(1-heptadecyl octadecylene)sorbitol

(17) 1.2:3.4:5.6-Tris-O-(1-methylidenepropylene)mannitol

(18) 1.3:2.4:5.6-Tris-O-(1-methylidenepropylene)mannitol

The above cyclic acetals can be appropriately produced by the production method of the second invention, but are not limited thereto.

In addition, the cyclic acetals of the second invention can be used not only as polar oils, organic solvents, lubricants, synthetic lubricating oils, and refrigerating machine oils, but also as surfactants, organic solvents, polar oils, and synthetic lubricating oils. , Refrigeration oil and other preparation intermediates.

The method for producing cyclic acetals of the second invention will be described below.

The preparation method of the present invention is characterized in that the hexahydric alcohol is reacted with a carbonyl compound (ketone or aldehyde) or its active derivative (ketal or acetal) in the presence of an acid catalyst. The reaction formula of this reaction is shown below. In the formula, R ⁵ and R ⁶ represent the same meaning as above; moreover, R ⁷ represents a linear or branched chain alkyl group with 1 to 6 carbon atoms.

That is, with an acid catalyst, the hexavalent alcohols such as sorbitol or mannitol shown in the formula (iii) and the carbonyl compounds such as ketones or aldehydes shown in the general formula (iv) or their active derivatives undergo dehydration reaction or dehydration. Alcohol reaction, give the cyclic acetals of general formula (i) or (ii). In the case of ketones, the general formula (i) is mainly obtained; in the case of aldehydes, mixtures of the general formulas (I) and (ii) can be obtained. Those with α-branched chain alkyl in aldehydes have more content of general formula (i). On the other hand, if the short-time reaction is performed, the content of the general formula (ii) increases.

As the hexahydric alcohol that can be used, those represented by the above-mentioned formula (iii) can be mentioned, specifically, hexitol obtained by reducing hexose, that is, sorbitol, mannitol, galactitol, carbitol, Duitol, talitol, allicitol, etc. Among them, sorbitol is the best from the viewpoint of availability or price.

The carbonyl compounds which can be used in the process of the second invention are ketones or aldehydes, wherein the ketones can be easily obtained by means of high-temperature decarboxylation dimerization of fatty acids or catalytic oxidation of olefins (Wacker method) or secondary alcohol oxidation, dehydrogenation or cyclization. It can be obtained by oxidation of alkanes. In the case of the Wacker method, the obtained ketone has a distribution, but it can be separated and refined into a pure product by rectification. Specific examples of ketones can be listed below, but not necessarily limited thereto.

For example, examples of methyl alkyl ketones include methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, methyl amyl ketone, methyl hexyl ketone, methyl heptyl ketone, and methyl heptyl ketone. methyl ketone, methyl octyl ketone, methyl nonyl ketone, methyl undecyl ketone, methyl heptadecyl ketone, etc.

Examples of dialkyl ketones include diethyl ketone, ethyl propyl ketone, ethyl butyl ketone, dipropyl ketone, ethyl amyl ketone, ethyl hexyl ketone, dibutyl ketone, Diamyl ketone, dihexyl ketone, di(undecyl) ketone, di(heptadecyl) ketone, etc.

Examples of highly branched ketones include methyl isopropyl ketone, methyl sec-butyl ketone, methyl isobutyl ketone, ethyl isopropyl ketone, methyl tert-butyl ketone, diisopropyl ketone, Propyl ketone, methyl isoamyl ketone, isopropyl propyl ketone, methyl neopentyl ketone, ethyl tert-butyl ketone, 6-methyl-2-heptanone, 4-methyl -3-heptanone, 2-methyl-3-heptanone, 5-methyl-3-heptanone, diisobutyl ketone, 6,10-dimethyl-2-undecanone, etc.

Furthermore, aldehydes which can be used are readily obtainable by means of processes such as dehydrogenation of fatty alcohols, hydroformylation of alkenes (oxo process), Rosenmund reduction of fatty acid chlorides or direct hydrogenation of fatty acids. In the case of oxo synthesis, straight-chain aldehydes and branched-chain aldehydes will be generated, but they can be separated and refined into pure products by rectification. Specific examples of each of the alkylaldehydes can be listed below, but not necessarily limited thereto.

For example, examples of linear alkyl aldehydes include valeraldehyde, hexanal, heptanal, octanal, decanal, dodecanal, tetradecylaldehyde, octadecylaldehyde, and behenaldehyde. wait.

Examples of α-branched alkylaldehydes include isobutyraldehyde, 2-methylbutyraldehyde, 2-methylpentanal, 2-ethylbutyraldehyde, 2-methylhexanal, 2-ethylpentanal, 2-methylheptanal, 2-ethylhexanal, 2-propylpentanal, etc.

As the α-multi-branched alkyl group having one or more branches in addition to the α-branch on the α-branch, 2,3-dimethylbutyraldehyde, 2,4,4-trimethylpentanal, Aldehydes, 2-isopropyl-5-methylhexanal, etc.

Other branched alkyl aldehydes having one or more branched chains other than α-branched chains include isovaleraldehyde, 3-methylpentanal, 4-methylpentanal, 3,3-dimethylbutanal, Aldehyde, 3-Methylhexanal, 4-Methylhexanal, 5-Methylhexanal, 3,5,5-Trimethylhexanal, Isodecanal, 3,7-Dimethyloctanal, Iso octadecyl aldehyde, etc.

In addition, as the active derivative of the carbonyl compound that can be used in the second invention, it is the general formula (iv') that can be easily synthesized from the above-mentioned ketone, aldehyde and lower alcohol with 1 to 6 carbon atoms by using an acid catalyst Ketals and acetals are shown. Specific examples of lower alcohols having 1 to 6 carbon atoms that can give R7 residues include methanol, ethanol, propanol, isopropanol, butanol, isobutanol, sec-butanol, tert-butanol, Pentanol, Isoamyl Alcohol, Neopentyl Alcohol, 1-Methylbutanol, 1,1-Dimethylpropanol, 1-Ethylpropanol, Hexanol, Isohexanol, 2-Ethylbutanol, 1- Methylpentanol, 1,3-dimethylbutanol, 1-ethylbutanol, etc.

In the second invention, the reaction of the hexahydric alcohol shown in the formula (iii) and the ketone is a ketalization reaction, and the molar ratio of the ketone to the hexahydric alcohol shown in the formula (iii) is 1.5～15, preferably 2.7～ 7.5. This reaction is carried out with acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid as catalyzer, with respect to the six alcohols shown in formula (iii), catalyst consumption is 0.1～10% (mol), preferably It is 1.0 to 5% (mol).

This reaction does not need a solvent, or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, petroleum petroleum, petroleum ether, or in a mixed solvent, because Depending on the boiling point of the ketone used, it is carried out at a temperature of 30 to 130°C, preferably at a temperature of 60 to 100°C, and it is preferable to remove the generated water while carrying out. If the temperature is within these ranges, the reaction is favored due to the tendency to reduce coloring due to side reactions. In addition, it can also be performed under any conditions such as nitrogen flow, nitrogen atmosphere, and dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably from 5 to 200 hours. The obtained cyclic ketal (i) or (ii) is neutralized and subjected to pretreatments such as filtration and washing, and then can be purified by adsorption treatment, crystallization, distillation and the like.

In addition, the reaction of the hexahydric alcohol represented by the formula (iii) and the aldehyde is an acetalization reaction, and the molar ratio of the aldehyde to the hexahydric alcohol represented by the formula (iii) is 1.5-6, preferably 2.7-3.8. This reaction uses acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid to carry out as a catalyst, with respect to the six alcohols shown in formula (iii), the catalyst consumption is 0.01～5% (mol), preferably 0.1 ~2% (mol).

This reaction does not use a solvent, or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, butane, petrolatum, petroleum ether, or a mixed solvent , depending on the boiling point of the aldehyde used, it is carried out at a temperature of 20 to 130°C, preferably at a temperature of 40 to 100°C, and it is preferable to remove the generated water while carrying out. If the temperature is within these ranges, the reaction is favored because there is a tendency to reduce coloration due to side reactions. In addition, it may be performed under any conditions such as a nitrogen flow, a nitrogen atmosphere, and a dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably 1 to 30 hours. After the obtained cyclic acetal (i) or (ii) is neutralized, it can be subjected to pretreatments such as filtration and washing, and then can be refined by operations such as adsorption treatment, crystallization, and distillation.

In addition, the reaction of hexahydric alcohol shown in formula (iii) and the active derivative ketal (iv') of ketone is a transketalization reaction, and the mole of ketal (iv') and hexahydric alcohol shown in formula (iii) The ratio is 1.5 to 15, preferably 2.7 to 7.5. This reaction uses acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid to carry out as a catalyst, with respect to the six alcohols shown in formula (iii), the catalyst consumption is 0.1～10% (mol), preferably 1.0 ~5% (mol).

This reaction does not need a solvent, or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, petroleum petroleum, petroleum ether, or in a mixed solvent, because Depending on the boiling point of the ketal (iv') used and the lower alcohol produced, it is carried out at a temperature of 40 to 150°C, preferably at a temperature of 70 to 130°C, and it is preferable to remove the lower alcohol produced while carrying out . If the temperature is within these ranges, the reaction is facilitated since there is less tendency for coloration due to side reactions. In addition, it can also be performed under any conditions such as nitrogen flow, nitrogen atmosphere, and dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably from 5 to 200 hours. The obtained cyclic ketal (i) or (ii) is neutralized and subjected to pretreatments such as filtration and washing, and then can be purified by adsorption treatment, crystallization, distillation and the like.

And then, the reaction of hexahydric alcohol shown in formula (iii) and the active derivative acetal (iv') of aldehyde is transacetalization reaction, the mole of acetal (iv') and hexahydric alcohol shown in formula (iii) The ratio is 1.5 to 6, preferably 2.7 to 3.8. This reaction uses acid catalysts such as p-toluenesulfonic acid, methanesulfonic acid, sulfuric acid to carry out as a catalyst, with respect to the six alcohols shown in formula (iii), the catalyst consumption is 0.01～5% (mol), preferably 0.1～ 2% (mol).

This reaction does not use a solvent, or in an inert solvent such as xylene, toluene, benzene, octane, isooctane, heptane, hexane, cyclohexane, pentane, butane, petrolatum, petroleum ether, or a mixed solvent , depending on the boiling point of the acetal (iv') used and the lower alcohol produced, it is carried out at a temperature of 20 to 150°C, preferably at a temperature of 50 to 130°C, and it is preferably carried out while removing the generated lower alcohols. If the temperature is within these ranges, the reaction is facilitated since there is less tendency for coloration due to side reactions. In addition, it can also be performed under any conditions such as nitrogen flow, nitrogen atmosphere, and dry air atmosphere. The reaction time varies depending on various conditions, but usually it is preferably 1 to 30 hours. After the obtained cyclic acetal (i) or (ii) is neutralized, it can be subjected to pretreatments such as filtration and washing, and then can be refined by operations such as adsorption treatment, crystallization, and distillation.

According to the production method of the second invention, in the case of using aldehyde as described above, a mixture of general formulas (i) and (ii) can be obtained, but as a method of separating the two, it can be separated and purified by ordinary organic compounds For example, separation can be performed by rectification, column chromatography, thin layer chromatography, fractional crystallization, preparative HPLC (liquid chromatography), preparative gas chromatography, and the like. However, since both are similar in physical properties, they can be used as synthetic lubricating oil, refrigerating machine oil, and the like without being separated.

According to the production method of the second invention, the above-mentioned cyclic acetals can be obtained in higher yield than the simple method.

Preparation examples, examples, synthesis examples, and test examples of the present invention are described below, but the present invention is not limited by these examples in any way. It is to be noted that the preparation examples and examples are related to the first invention, and the synthesis examples and test examples are related to the second invention.

Preparation Example 1

Install a stirrer, a thermometer, a nitrogen pipe and a dehydration pipe with a condenser on a 3-liter 4-neck flask. 336.8 g (1.85 mol) of D-sorbitol, 800.0 g (11.1 mol) of methyl ethyl ketone, 17.6 g (0.092 mol) of p-toluenesulfonic acid monohydrate, and 200 ml of hexane were added to the flask. Under a nitrogen atmosphere, the reaction was carried out at normal pressure at 69-79° C. for 8 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 19.6 g (0.185 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 200 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 200 g of saturated brine, and hexane and excess methyl ethyl ketone were removed under reduced pressure with a rotary evaporator. Further distillation under reduced pressure gave cyclic ketal A ₁ (hydroxyl value 12.9 mgKOH/g, gas chromatography purity 97.3%). Then, a part of cyclic ketal A ₁ was further purified by column chromatography to obtain cyclic ketal A ₂ (hydroxyl value: 0.0 mgKOH/g, purity by gas chromatography: 99.8%).

Preparation example 2

Install a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser on a 3 L 4-neck flask. Add 450.0 g (2.47 mol) of D-sorbitol, 588.0 g (8.15 mol) of isobutyraldehyde, 4.7 g (0.025 mol) of p-toluenesulfonic acid monohydrate and petroleum ether with a boiling point of 30 to 60° C. 400ml. In a dry air atmosphere, the reaction was carried out at normal pressure at 40-65° C. for 15 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 5.24 g (0.049 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, wash with saturated brine 100g, remove sherwood oil and excess isobutyraldehyde under reduced pressure with a rotary evaporator, and further distill under reduced pressure to obtain cyclic acetal B (hydroxyl value 6.0mgKOH/g, gas chromatograph Method purity 99.0%).

Preparation example 3

Install a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser on a 3-liter 4-neck flask. 450.0 g (2.47 mol) of D-sorbitol, 588.0 g (8.15 mol) of n-butyraldehyde, 4.7 g (0.025 mol) of p-toluenesulfonic acid monohydrate, and 400 ml of hexane were added to the flask. In a dry air atmosphere, the reaction was carried out at normal pressure at 62-83° C. for 5 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 5.24 g (0.049 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, wash with saturated brine 100g, remove hexane and excess n-butyraldehyde under reduced pressure with a rotary evaporator, and further distill under reduced pressure to obtain cyclic acetal C ₁ (hydroxyl value 13.1mgKOH/g, gas phase Chromatographic purity 97.8%). Then, a part of cyclic acetal _C1 was further purified by column chromatography to obtain cyclic acetal _C2 (hydroxyl value: 4.1 mg KOH/g, purity by gas chromatography: 99.3%).

Preparation Example 4

Install a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser on a 3-liter 4-neck flask. 363.8 g (2.00 mol) of D-sorbitol, 1200 g (12.0 mol) of methyl isobutyl ketone, 18.99 g (0.100 mol) of p-toluenesulfonic acid monohydrate, and 300 ml of hexane were added to the flask. Under a dry air atmosphere, the reaction was carried out at 93-98° C. under normal pressure for 23 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 21.16 g (0.200 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 200 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 200 g of saturated brine, hexane and excess methyl isobutyl ketone were removed under reduced pressure with a rotary evaporator, and low boiling point components were further removed by vacuum distillation. 657.6 g of the obtained crude ketal was filtered through activated clay to obtain cyclic ketal D ₁ (hydroxyl value: 34.3 mgKOH/g, gas chromatography purity: 93.1%). Part of the cyclic ketal D ₁ was further purified by column chromatography to obtain a cyclic ketal D ₂ (hydroxyl value 0.0 mgKOH/g, purity 99.6% by gas chromatography).

Preparation Example 5

Install a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser on a 3-liter 4-neck flask. Add D-sorbitol 170.8g (0.937mol), 3,5,5-trimethylhexanal 400.0g (2.81mol), p-toluenesulfonic acid-hydrate 1.78g (0.0094mol) and Alkanes 400ml. Under dry air atmosphere, the reaction was carried out at normal pressure at 79-81° C. for 8 hours, and the water was distilled off. After completion of the reaction, it was cooled to 70°C, and 1.99 g (0.019 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, followed by stirring at 70°C for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 100 g of saturated brine, hexane was removed under reduced pressure with a rotary evaporator, and low boiling point components were further removed by vacuum distillation. Add 500 ml of hexane to 500.9 g of the obtained crude acetal, filter through activated clay, then remove hexane under reduced pressure with a rotary evaporator to obtain cyclic acetal E (hydroxyl value 27.2 mgKOH/g, gas chromatography Purity 93.2%).

Preparation example 6

Install a stirrer, a thermometer, a nitrogen pipe and a dehydration pipe with a condenser on a 1-liter 4-necked flask. 166.0 g (1.00 mol) of diglycerin, 288.0 g (4.00 mol) of methyl ethyl ketone, 3.80 g (0.020 mol) of p-toluenesulfonic acid monohydrate, and 100 ml of hexane were added to the flask. Under a nitrogen atmosphere, the reaction was carried out at normal pressure at 66-81° C. for 15 hours, and water was distilled off. After completion of the reaction, it was cooled to 60° C., and 4.24 g (0.040 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 100 g of water, hexane and excess methyl ethyl ketone were removed under reduced pressure using a rotary evaporator, and low boiling point components were further removed by vacuum distillation. 0.6 g of activated alumina was added to 223.0 g of the obtained crude ketal, and it stirred at 50 degreeC for 30 minutes. After filtration, cyclic ketal F ₁ (hydroxyl value: 15.7 mgKOH/g, gas chromatography purity: 96.7%) was obtained. Then, a part of cyclic ketal F ₁ was further purified by column chromatography to obtain cyclic ketal F ₂ (hydroxyl value: 0.0 mgKOH/g, purity by gas chromatography: 99.7%).

Preparation Example 7

Install a stirrer, a thermometer, a nitrogen pipe and a dehydration pipe with a condenser on a 1-liter 4-neck flask. 100.0 g (0.602 mol) of diglycerin, 180.8 g (1.81 mol) of methyl isobutyl ketone, 2.29 g (0.012 mol) of p-toluenesulfonic acid monohydrate, and 300 ml of toluene were added to the flask. Under a nitrogen atmosphere, the reaction was carried out at normal pressure at 110-119° C. for 55 hours, and water was distilled off. After completion of the reaction, it was cooled to 60° C., and 2.54 g (0.024 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, wash with 50 g of saturated brine, remove toluene and excess methyl isobutyl ketone under reduced pressure with a rotary evaporator, and further distill under reduced pressure to obtain cyclic ketal G ₁ (hydroxyl value: 26.2 mgKOH /g, gas chromatography purity 95.1%)). Then, a part of cyclic ketal _G1 was further purified by column chromatography to obtain cyclic ketal _G2 (hydroxyl value: 1.6 mgKOH/g, purity by gas chromatography: 99.5%).

Preparation example 8

Install a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser on a 3 L 4-neck flask. 332.4 g (2.00 mol) of diglycerin, 853.4 g (6.00 mol) of diisobutyl ketone, 7.61 g (0.040 mol) of p-toluenesulfonic acid monohydrate, and 500 ml of hexane were added to the flask. Under dry air flow, the reaction was carried out at 96-97°C under normal pressure for 123 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 8.48 g (0.080 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 100 g of saturated brine, hexane was removed under reduced pressure with a rotary evaporator, and diisobutyl ketone was further distilled off under reduced pressure. Add 400 ml of hexane to 666.7 g of the obtained crude ketal, filter through activated clay, then remove hexane under reduced pressure with a rotary evaporator to obtain cyclic ketal H (hydroxyl value: 4.0 mgKOH/g, gas chromatograph Method purity 98.0%).

Preparation Example 9

Install a stirrer, a thermometer, a nitrogen pipe and a dehydration pipe with a condenser on a 1-liter 4-neck flask. Add 166.0 g (1.00 mol) of diglycerol, 289.7 g (2.04 mol) of 3,5,5-trimethylhexanal, 1.90 g (0.010 mol) of p-toluenesulfonic acid hydrate and 150 ml of hexane in the said flask . Under nitrogen flow, the reaction was carried out at normal pressure at 75-92° C. for 8 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 2.12 g (0.020 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 100 g of saturated brine, hexane was removed under reduced pressure with a rotary evaporator, and low boiling point components were further removed by vacuum distillation. 1.2 g of activated alumina was added to 405.5 g of the obtained crude acetal, and stirred at 50° C. for 30 minutes. After filtration, cyclic acetal I ₁ was obtained (hydroxyl value: 23.1 mgKOH/g, purity by gas chromatography: 94.3%). Then, a part of cyclic acetal I1 was further purified by column chromatography to obtain cyclic acetal I ₂ (hydroxyl value: 2.7 mgKOH/g, purity by gas chromatography: 99.1%).

Preparation Example 10

Install a stirrer, a thermometer, a nitrogen pipe and a dehydration pipe with a condenser on a 1-liter 4-neck flask. 100.0 g (0.602 mol) of diglycerin, 205. g (1.20 mol) of 6-undecanone, 2.29 g (0.012 mol) of p-toluenesulfonic acid monohydrate and 300 ml of toluene were added to the flask. Under nitrogen flow, the reaction was carried out at 122-124° C. under normal pressure for 48 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 2.54 g (0.024 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, wash with 50 g of saturated brine, remove toluene under reduced pressure with a rotary evaporator, and further distill under reduced pressure to obtain cyclic ketal J ₁ (hydroxyl value 13.2 mgKOH/g, gas chromatography purity 96.5%) . Then, a part of the cyclic ketal J ₁ was further purified by column chromatography to obtain a cyclic ketal J ₂ (hydroxyl value: 0.9 mgKOH/g, purity by gas chromatography: 99.0%).

Preparation Example 11

Install a stirrer, a thermometer, a nitrogen pipe and a dehydration pipe with a condenser on a 1-liter 4-neck flask. 122.0 g (1.00 mol) of mesoerythritol, 288.0 g (4.00 mol) of methyl ethyl ketone, 3.80 g (0.020 mol) of p-toluenesulfonic acid monohydrate, and 100 ml of hexane were added to the flask. Under a nitrogen atmosphere, the reaction was carried out at 63-78° C. under normal pressure for 15 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 4.24 g (0.040 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, wash with 100 g of water, remove hexane and excess methyl ethyl ketone under reduced pressure with a rotary evaporator, and further carry out distillation under reduced pressure to obtain cyclic ketal K (hydroxyl value 1.0 mgKOH/g, gas phase Chromatographic purity 99.4%).

Preparation Example 12

Install a stirrer, a thermometer, a calcium chloride tube, and a dehydration tube with a condenser on a 3 L 4-neck flask. Add meso-erythritol 270.0g (2.21mol), 3,5,5-trimethylhexanal 629.0g (4.42mol), p-toluenesulfonic acid-hydrate 4.21g (0.022mol) in the flask and hexane 600ml. In a dry air atmosphere, the reaction was carried out at normal pressure at 76-83° C. for 7 hours, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 4.68 g (0.040 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 100 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 100 g of saturated brine, hexane was removed under reduced pressure with a rotary evaporator, and low boiling point components were further removed by vacuum distillation. Add 400 ml of hexane to 781.8 g of the obtained crude acetal, filter through activated clay, then remove hexane under reduced pressure with a rotary evaporator to obtain cyclic acetal L ₁ (hydroxyl value 20.2 mgKOH/g, gas phase Chromatographic purity 95.3%). Then, a part of cyclic acetal _L1 was further purified by column chromatography to obtain cyclic acetal L2 (hydroxyl value: 5.1 mgKOH/g, purity by gas chromatography: 98.0%).

Preparation Example 13

Install a stirrer, a thermometer, a nitrogen pipe and a dehydration pipe with a condenser on a 3-liter 4-neck flask. 336.8 g (1.85 mol) of D-mannitol, 800.0 g (11.1 mol) of methyl ethyl ketone, 17.6 g (0.092 mol) of p-toluenesulfonic acid monohydrate, and 200 ml of hexane were added to the flask. Under a nitrogen atmosphere, the reaction was carried out at 68-76° C. for 10 hours at normal pressure, and the water was distilled off. After completion of the reaction, it was cooled to 60° C., and 19.6 g (0.185 mol, 2 times the equivalent of p-toluenesulfonic acid) of sodium carbonate was added for neutralization, and stirred at 60° C. for 30 minutes. Add 200 g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 200 g of saturated brine, and hexane and excess methyl ethyl ketone were removed under reduced pressure with a rotary evaporator. It was further distilled under reduced pressure and purified by column chromatography to obtain a cyclic ketal M (hydroxyl value: 0.2 mgKOH/g, purity by gas chromatography: 99.6%).

Preparation Example 14

Install a stirrer, a thermometer, and a dehydration tube with a condenser on a 3-liter 4-necked flask. 500 g (3.73 mol) of tris(hydroxymethyl)propane, 777 g (7.46 mol) of 2,2-dimethoxypropane, and 14.17 g (0.075 mol) of p-toluenesulfonic acid monohydrate were added to the flask. Under a nitrogen atmosphere, the reaction was carried out at 60-70° C. under normal pressure for 2 hours, and the methanol was distilled off. After the reaction, carry out the same aftertreatment as in Preparation Example 13, and further carry out vacuum distillation to obtain 1,3-dioxa-5-ethyl-2,2-dimethyl-5-cyclohexylmethanol (Na) 584.9 g (yield 90%, hydroxyl value 322.6 mgKOH/g).

Install a stirrer, a thermometer, a condenser, and a dropping funnel on a 2-liter 4-necked flask, and perform nitrogen replacement. Add 20.0 g (0.5 mol) of sodium hydride (content 60%, oily), 450 ml of 1,2-dimethoxyethane and 150 ml of dimethyl sulfoxide into the flask. Under a nitrogen atmosphere, 87.1 g (0.5 mol) of the compound (Na) obtained above was added dropwise at room temperature over 15 minutes, stirred for a further 1 hour, and then ethylene glycol di-p-toluenesulfonate (Tokyo Kasei Co., Ltd.) powder 77.0 g (0.208 mol). Stir overnight at 70°C under a nitrogen atmosphere, then add 750 ml of water and 500 ml of diethyl ether, separate layers, and extract the aqueous layer twice with 300 ml of diethyl ether. The organic layers were combined, washed three times with 300 ml of 5% aqueous sodium carbonate solution, and dried with a mixture of anhydrous sodium sulfate and anhydrous sodium carbonate. The solvent was removed with a rotary evaporator to obtain 115.3 g of an oily substance. It is further purified by silica gel column chromatography (using hexane/ethyl acetate as developing solvent) to obtain ethylene glycol bis[1,3-dioxa-5-ethyl-2,2-dimethyl-5 - Cyclohexyl] methyl ether (Nb) 51 g (column chromatography purity 99%, hydroxyl value 0.0 mgKOH/g).

Install a stirrer, a thermometer, and a condenser on a 1-liter 4-necked flask. 50 g (0.13 mol) of the compound (Nb) obtained above, 500 ml of ethanol, and 50 ml of 1N hydrochloric acid were added to the flask. Under a nitrogen atmosphere, the mixture was refluxed at 80-100°C for 5 hours, then cooled to room temperature, and neutralized with 1N sodium hydroxide. The solvent was completely distilled off under reduced pressure, and the obtained residue was dissolved in water, and the water was removed after electrodialysis to obtain 2,9-diethyl-2,9-bis(hydroxymethyl)-4,7-bis Oxadecane-1,10-diol (Nc) 37.6 g.

Install a stirrer, a thermometer, and a dehydration tube with a condenser on a 300ml 4-necked flask. Into the flask were charged 37 g (0.13 mol) of the compound (Nc) obtained above, 28.1 g (0.39 mol) of methyl ethyl ketone, 0.49 g (0.0026 mol) of p-toluenesulfonic acid monohydrate, and 50 g of hexane. Under a nitrogen atmosphere, the reaction was carried out at 60-70° C. under normal pressure for 8 hours, and the water was distilled off. After completion of the reaction, the same aftertreatment as in Preparation Example 13 was performed, and the solvent was removed by a rotary evaporator to obtain 52.3 g of an oily substance. It is further purified by silica gel column chromatography (using hexane/ethyl acetate as developing solvent) to obtain ethylene glycol bis[1,3-dioxa-2,5-diethyl-2-methyl-5 - 45 g of cyclohexyl] methyl ether (cyclic ketal N) (column chromatography purity 98.5%, hydroxyl value 0.0 mgKOH/g).

Preparation Example 15

Add 292.1 g (2.18 mol) of tris(hydroxymethyl)propane, 474.0 g (8.17 mol) of acetone, 6.0 g (0.0315 mol) of p-toluenesulfonic acid hydrate and 900 ml of hexane into a 3-liter reaction vessel, and reflux for 24 hours , to remove the produced water to the outside of the system. The reactant was neutralized with aqueous sodium hydroxide solution and then distilled under reduced pressure to synthesize 5-hydroxymethyl-5-ethyl-2,2-dimethyl-1,3-dioxane.

Then, the above-mentioned 5-hydroxymethyl-5-ethyl-2,2-dimethyl-1,3-bis 17.4g (0.1mol) of oxane, 0.19g (0.001mol) of 28% (weight) sodium methoxide in methanol and 5ml of toluene were slowly depressurized (0.4mmHg) from normal pressure for 1 hour under heating at 110°C to make Low boiling point components are distilled from the gas discharge pipe. After sealing, 58.0 g (1.0 mol) of propylene oxide was introduced into the autoclave through the liquid introduction pipe at 110° C. over 8 hours. After cooling, add 28% (weight) sodium methylate methanol solution 21.2g (0.11mol) and toluene 150ml in the reactant, under heating at 110 ℃, slowly reduce pressure (0.4mmHg) from normal pressure (0.4mmHg) with the time of 2 hours, make low Boiling point components evaporate from the gas discharge pipe.

After cooling, 15.6 g (0.11 mol) of methyl iodide was added, sealed, heated at 60° C. for 3 hours, and further heated at 90° C. for 5 hours. After cooling, 2.8 g of Kyoward 600 (alkali adsorbent, manufactured by Kyowa Chemical Industry Co., Ltd.) was added, stirred for 1 hour, and filtered to obtain oil fa (purity by gas chromatography: 78%) for a comparative product. A part of fa was further purified by column chromatography to obtain oil f (purity by gas chromatography: 85%) for comparison.

Example 1

The hydroxyl values (JISK-0070) of the cyclic ketals or cyclic acetals A ₁ to N used in the products of the present invention obtained in the production examples were measured, and the unreacted hydroxyl groups and the raw material polyols obtained from the hydroxyl values were measured. The ratio of the number of hydroxyl groups, the dynamic viscosity (JISH-2283) at 40°C and 100°C, and the pour point (JISK-2269). The results are listed in Table 1. In addition, the dynamic viscosities (JISK-2283) and pour points (JISK-2269) at 40° C. and 100° C. of the oils a to f used as comparative products were measured. The results are listed in Table 2.

Table 1 Cyclic Ketal · Acetal Viscosity at 40°C (mm ² /s) Viscosity at 100℃(mm ² /s) Pour point (°C) Alcohol Raw material ketone and aldehyde Hydroxyl value (mgKOH/g) Unreacted Hydroxyl (%) A ₁ Sorbitol Methyl ethyl ketone 12.9 1.3 66.9 4.62 -32.5 A ₂ Sorbitol Methyl ethyl ketone 0.0 0.0 63.1 4.54 -32.5 B Sorbitol Isobutylaldehyde 6.0 0.61 167.8 5.81 -25.0 C ₁ Sorbitol n-Butylaldehyde 13.1 1.3 68.2 5.49 -37.5 C ₂ Sorbitol n-Butylaldehyde 4.1 0.42 65.6 5.42 -37.5 D ₁ Sorbitol Methyl isobutyl ketone 34.3 4.2 62.3 5.61 -27.5 D2 Sorbitol Methyl isobutyl ketone 0.0 0.0 53.9 5.36 -27.5 E. Sorbitol 3,5,5-Trimethylhexanal 27.2 4.3 394.6 15.5 -20.0＞ F ₁ Diglycerin Methyl ethyl ketone 15.7 1.9 7.69 1.97 -45.0＞ F ₂ Diglycerin Methyl ethyl ketone 0.0 0.0 6.82 1.87 -45.0＞ G ₁ Diglycerin Methyl isobutyl ketone 26.2 3.8 9.08 2.35 -20.0＞ _G2 Diglycerin Methyl isobutyl ketone 1.6 0.24 7.83 2.16 -20.0＞

Table 1 (continued)

Table 2

Example 2

The cyclic ketals or cyclic acetals A ₁ to D ₂ , F ₁ to I ₂ , K, M, N and 1,1,1,2-tetrafluoro Ethane (HFC-134a), or a mixture of 1,1,1,2-tetrafluoroethane and difluoromethane (HFC-32), or 1,1,1,2-tetrafluoroethane and difluoroethane Compatibility of mixed refrigerants of fluoromethane and pentafluoroethane (HFC-125).

The cyclic ketals or cyclic acetals A ₁ ~ D ₂ , F ₁ ~ I ₂ , K, M, N and 1,1,1,2-tetrafluoroethane (HFC- 134a), or 1,1,1,2-tetrafluoroethane and difluoromethane (HFC-32) mixed refrigerant, or 1,1,1,2-tetrafluoroethane and difluoromethane and pentafluoro Compositions of ethane (HFC-125) mixed refrigerants, namely products 1 to 20 of the present invention, and combinations of oil a (naphthenic oil) and 1,1,1,2-tetrafluoroethane used in comparative products The two-phase separation temperature of the comparative product 1 at low temperature. The results are listed in Table 3.

It can be seen from Table 3 that the product of the present invention has excellent compatibility with hydrofluorocarbons at low temperatures. Among the products of the present invention, the composition of cyclic ketals or cyclic acetals A ₁ , A ₂ , B, D ₁ , D ₂ , F ₁ , F ₂ , G ₂ , K, and M is particularly excellent. In addition, cyclic ketals A ₁ and A ₂ (invention products 1 and 2), D ₁ and D ₂ (invention products 6 and 7), cyclic acetals I ₁ and I ₂ (invention products 11 and 17 ) for comparison, it can be seen that the less unreacted hydroxyl groups, the better the compatibility with hydrofluorocarbons.

table 3 composition Two-phase separation temperature (°C) oil species Hydrofluorocarbons Oil concentration (volume%) 1 6 10 20 30 40 50 Product of the present invention 1 Cyclic Ketal A ₁ HFC134a -67 -55 -60 -67 -66 -68 -69 2 Cyclic Ketal A ₂ HFC134a -70＞ -70＞ -70＞ -70＞ -70＞ 3 Cyclic Ketal A ₂ HFC134a/HFC32 (70/30 weight ratio) -70＞ -70＞ -57 -53 -54 -57 4 Cyclic acetal B HFC134a -70＞ -62 -44 -39 -39 -42 5 Cyclic acetal C ₁ HFC134a 9 13 14 15 15 6 Cyclic Ketal D ₁ HFC134a -4 2 6 5.5 5 7 Cyclic ketal D ₂ HFC134a -17 -1 5 4.5 2 8 Cyclic Ketal F ₁ HFC134a -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ 9 Cyclic Ketal F ₁ HFC134a/HFC32 (70/30 weight ratio) -70＞ -70＞ -70＞ -70＞ -70＞ 10 Cyclic ketal H HFC134a -10 13 16 13 4 11 Cyclic acetal I ₁ HFC134a -13 10 14 11 -2 Comparative product 1 a (naphthenic oil) HFC134a 20＜ 20＜ 20＜ 20＜ 20＜ 20＜ Table 3 (continued) composition Two-phase separation temperature (°C) oil species Hydrofluorocarbons Oil concentration (volume%) Product of the present invention 1 6 10 20 30 40 50 12 Cyclic Ketal A ₂ HFC134a/HFC32/HFC125 (52/23/25 weight ratio) -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ 13 Cyclic Ketal F ₂ HFC134a -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ 14 Cyclic Ketal F ₂ HFC134a/HFC32 (70/30 weight ratio) -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ 15 Cyclic acetal F ₂ HFC134a/HFC32/HFC125 (52/23/25 weight ratio) -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ 16 Cyclic Ketal G ₂ HFC134a -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ -70＞ 17 Cyclic Ketal I ₂ HFC134a -19 9 12 9 3 18 Cyclic ketal K HFC134a -27 -20 -17 -15 -15 19 Cyclic ketal M HFC134a -46 -38 -30 -27 -28 20 Cyclic ketal N HFC134a -70＞ -70＞ -70＞ -70＞ -70＞

Example 3

Compatibility at high temperature of Invention Product 2, which is a composition of cyclic ketal _A2 and 1,1,1,2-tetrafluoroethane (HFC-134a) obtained in the preparation example and used in the present invention . Add 60.0g of cyclic ketal _A2 and 240.0g of HFC-134a to a 372cm ³ autoclave equipped with a sight glass, heat from room temperature to 100°C while stirring properly, and observe the separation state of the mixed solution visually.

Invention product 2 (oil concentration 20% by weight) was uniformly dissolved from room temperature to 100°C, and no separation was observed. Also get 20.0g cyclic ketal A ₂ and 380.0g HFC-134a, examine its separation state, also show that the product 2 of the present invention (oil concentration 5% (weight)) all is dissolved uniformly from room temperature to 100 ℃, without A detached state was observed.

Similarly, the product 2 of the present invention having an oil concentration of 10% by weight, 30% by weight, 40% by weight, and 50% by weight also showed uniform dissolution from room temperature to 100°C, and no separation was observed. state.

Example 4

Consider the cyclic ketals A ₁ , A ₂ , B, C ₂ , D ₁ , D ₂ , F ₂ , I ₁ , J ₂ , K, L ₁ , M, N obtained in the preparation examples and used in the products of the present invention Electrical insulation properties of oil b (polyalkylene glycol) and f used as comparative products. In addition, the electrical insulation of the mixture (50:50 (weight ratio)) of the cyclic ketal _A2 and the oil b used as a comparative product was also examined similarly.

The measurement was performed in accordance with JISC-2101, that is, the volume resistivity at 25°C was measured. The results are listed in Table 4.

Table 4 oil species Volume resistivity (Ω·cm) The oil used in the product of the present invention Cyclic ketal A ₁ cyclic ketal A ₂ cyclic ketal D ₁ cyclic ketal D ₂ cyclic ketal A ₂ + oil b (50:50 weight ratio) cyclic acetal B for comparative product Cyclic acetal C ₂ Cyclic ketal F ₂ Cyclic acetal I ₂ Cyclic ketal J ₂ Cyclic ketal K Cyclic acetal L ₂ Cyclic ketal M Cyclic ketal N 1.7×10 ¹⁵ 9.4×10 ^{15 4.7} ×10 ¹⁴ 5.8×10 ¹⁵ 1.5×10 ¹³ 3.6×10 ^{14 1.7} ×10 ^{13 2.1} ×10 15 1.8×10 14 1.3×10 ¹⁴ 8.9×10 ¹⁵ 7.8×10 ¹⁵ 3.9× 10 ¹⁵ 5.4×10 ¹² Oil for Comparative Example b(polyalkylene glycol) 7.8×10 ¹¹ f 8.3×10 ¹¹

As can be seen from Table 4, the volume resistivity of the product of the present invention is high, and the electrical insulation is better than that of Comparative Examples b and f. In addition, mixing the cyclic ketal or cyclic acetal used in the product of the present invention with polyalkylene glycol can also improve the electrical insulation of the polyalkylene glycol. Furthermore, the comparison of the cyclic ketals A ₁ and A ₂ , and D ₁ and D ₂ also shows that the less unreacted hydroxyl group, the better the electrical insulation. Furthermore, the comparison of cyclic ketal A ₂ with cyclic acetals B, C ₂ also shows that the cyclic ketal A ₂ obtained from ketones has better electrical insulation than the cyclic acetals B, C ₂ obtained from aldehydes sex. Through NMR (nuclear magnetic resonance) analysis and gas chromatography analysis, it is shown that the cyclic ketal A ₂ is all IIIa structures, while the IIIa structure/IIIb structure ratios of the cyclic acetals B and C are 56/44, 36/66 respectively. Therefore, those having a 1,3-dioxolane structure are more excellent in electrical insulation. On the other hand, the cyclic ketal N having two ether bonds in the polyol moiety is electrically insulating compared to the cyclic ketals or cyclic acetals A to M having one ether bond or no ether bond in the polyol moiety. Sex is poor.

Example 5

In order to examine the cyclic ketals or cyclic acetals A ₁ , A ₂ , B, D ₂ , F ₁ , G ₂ , K, M and 1, 1, 1, 2 obtained in the preparation examples and used in the products of the present invention -Tetrafluoroethane (HFC-134a), or a mixed refrigerant of 1,1,1,2-tetrafluoroethane and difluoromethane, or 1,1,1,2-tetrafluoroethane and difluoromethane The thermal stability of the composition of the mixed refrigerant of pentafluoroethane, that is, the products 1, 2, 3, 4, 7, 8, 12, 16, 18, and 19 of the present invention, was carried out under the conditions shown below. .

That is, 10 g of lubricating oil prepared in advance with a moisture concentration of 10 ppm or less and an acid value of 0.03 (mgKOH/g) or less is put into a glass tube together with 5 g of hydrofluorocarbon, and iron, copper, and aluminum are added as catalysts, and the tube is sealed. Carry out the test at 175°C for 14 days, then inspect the appearance of the composition of hydrofluorocarbon and oil and whether there are precipitates, open the sealed tube, remove hydrofluorocarbon, and then measure the acid value of the oil. The results are listed in Table 5.

It can be seen from Table 5 that the products of the present invention have good appearance, no precipitates, no increase in acid value, and good thermal stability.

table 5 Physical properties after test Exterior Precipitate or not Acid value of oil (mgKOH/g) Product of the present invention 1 no change none 0.03＞ 2 no change none 0.03＞ 3 no change none 0.03＞ 4 no change none 0.03＞ 7 no change none 0.03＞ 8 no change none 0.03＞ 12 no change none 0.03＞ 16 no change none 0.03＞ 18 no change none 0.03＞ 19 no change none 0.03＞

Example 6

In order to examine the cyclic ketals or cyclic acetals A ₁ , A ₂ , B, D ₂ , F ₁ , G ₂ , K, M and 1, 1, 1, 2 obtained in the preparation examples and used in the products of the present invention -Tetrafluoroethane (HFC-134a), or a mixed refrigerant of 1,1,1,2-tetrafluoroethane and difluoromethane, or 1,1,1,2-tetrafluoroethane and difluoromethane The composition of the mixed refrigerant of pentafluoroethane is the product 1, 2, 3, 4, 7, 8, 12, 16, 18, 19 of the present invention and the oil c, d (ester) and 1 used in the comparative product , 1,1,2-Tetrafluoroethane (HFC-1 34a) composition, that is, the thermal stability of comparative products 2 and 3 in the presence of water, the sealing test was performed under the conditions shown below. In addition, the composition of cyclic ketal A1 and oil c used in the comparative product (50:50 weight ratio) and 1,1,1,2-tetrafluoroethane (HFC-134a) is the product of the present invention 21, the same test was carried out.

That is, 10 g of lubricating oil prepared in advance with a water concentration of 3000 ppm and an acid value of 0.03 (mgKOH/g) or less is put into a glass tube together with 5 g of hydrofluorocarbon, and iron, copper, and aluminum are added as catalysts, and the tube is sealed. After testing at 175°C for 14 days, observe the appearance of the composition of hydrofluorocarbon and oil and whether there are precipitates, open the sealed tube, and measure the acid value of the oil after removing the hydrofluorocarbon. The results are listed in Table 6.

It can be seen from Table 6 that the products of the present invention have good appearance, no precipitates and no increase in acid value, and the thermal stability in the presence of water is good. In addition, as shown in product 21 of the present invention, hydrolysis of the ester can be prevented by adding the cyclic ketal or cyclic acetal of the present invention to the ester.

Table 6 Physical properties after test Exterior Precipitate or not Acid value of oil (mgKOH/g) Product of the present invention 1 no change none 0.03＞ 2 no change none 0.03＞ 3 no change none 0.03＞ 4 no change none 0.03＞ 7 no change none 0.03＞ 8 no change none 0.03＞ 12 no change none 0.03＞ 16 no change none 0.03＞ 18 no change none 0.03＞ 19 no change none 0.03＞ twenty one no change none 0.03＞ Comparative product 2 no change none 6.7 3 no change none 4.4

Example 7

The composition of cyclic ketal or cyclic acetal A ₁ , B and 1,1,1,2-tetrafluoroethane (HFC-134a) obtained in the preparation example and used in the product of the present invention is the present invention 1 , 4, and the composition of oil d, e (ester) and 1,1,1,2-tetrafluoroethane (HFC-134a) used for comparative products, that is, comparative products 3 and 4, and the Falex test was used to investigate the resistance Abrasive.

Heat 100ml of oil to 80°C, pass through 1,1,1,2-tetrafluoroethane (HFC-134a) at a rate of 10L per hour, operate with a load of 150 (1b) for 4 hours, and measure V after operation Amount of wear of slider (block) and pin (pin). The results are listed in Table 7.

As can be seen from Table 7, the products of the present invention have a small amount of wear and are excellent in wear resistance.

Table 7 Abrasion (mg) Product of the present invention 1 Product of the present invention 4 3.71.5 Comparator 3 Comparator 4 16.48.1

Example 8

The hygroscopicity of the cyclic ketal _A2 used in the product of the present invention obtained in the preparation example and the oils b (polyalkylene glycol) and c (ester) used in the comparative product were examined.

Add 2g of oil prepared in advance to make the water concentration below 50ppm into a glass tube with an inner diameter of 18mm and a volume of about 10ml, and place it in a constant temperature bath at 25°C and a humidity of 80%. After standing for a certain period of time, the water concentration of the oil was measured by the Karl Fischer method (JISK-2275). The results are listed in Table 8.

As can be seen from Table 8, the hygroscopicity of the cyclic ketals or cyclic acetals used in the products of the present invention is much lower than that of polyalkylene glycols, but about the same as that of esters.

Table 8 Moisture concentration (ppm) 0 day 1 day 3 days 6th 9th Oil _A2 for use in the invention 45 1,965 2,575 2,588 2,697 Oil b for comparator 47 13,400 17,600 19,100 19,800 oil c for comparison twenty three 1,352 1,742 1,780 1,779

Example 9

Compressor tests were carried out using a commercially available rotary compressor for the cyclic ketals A ₁ and A ₂ used in the product of the present invention obtained in the preparation examples and the oil e (ester) used in the comparative product.

Inject 170g of oil prepared in advance to make the water concentration below 20ppm and 60g of 1,1,1,2-tetrafluoroethane (HFC-134a) into the rotary compressor, and carry out continuous operation for 500 hours at the compressor shell temperature of 140°C. run.

After 500 hours, the cyclic ketals A ₁ and A ₂ showed less coloring and no change in the hydroxyl value compared with the oil e used in the comparative product, and no decomposition was observed in gas chromatography analysis or gel permeation chromatography analysis. The presence of substances or polymers indicates that the stability of the oil is good. In addition, as shown in Table 9, the cyclic ketals A ₁ and A ₂ exhibited less abrasion than the oil e used for the comparative product in terms of abrasion of sliding parts, and therefore had excellent lubricity. In addition, the cyclic ketals A ₁ and A ₂ are less than the oil e used for the comparative product in terms of the state of sludge adhesion at the discharge portion, and thus are good.

Table 9 Wear at the end of the impeller Sticking on the side of the impeller Oil A ₁ for use in the invention 5μm none Oil _A2 for use in the invention 5μm none Oil e used for comparator 20μm have

Example 10

For the cyclic ketal A ₂ obtained in the preparation example and used in the product of the present invention, its lubricity was investigated by Falez test.

Add cyclic ketal A ₂ to low-sulfur light oil (S=0.04%) to make it 50ppm, and operate at 150(1b) load for 3 hours in an atmosphere of 25°C, and measure the V slide (block ) and pin wear. The results are listed in Table 10.

As can be seen from Table 10, compared with the comparative product 5 without adding _A2 , the product 22 of the present invention to which cyclic ketal _A2 has been added has a small amount of abrasion, and is comparable to light oil with a sulfur concentration of 0.2% (comparative product 6). The amount of wear was also small compared to , indicating excellent lubricity.

Table 10 Abrasion (mg) Product of the present invention 22 Low sulfur light oil (S=0.04%)+cyclic ketal A ₂ 50ppm 20.0 Comparative product 5 Low sulfur light oil (S=0.04%) 38.0 Comparative product 6 Light oil (0.2%) 24.8

Example 11

For the cyclic ketal A ₂ obtained in the preparation example and used in the product of the present invention, its lubricity was examined by Soda'spendulum test.

The cyclic ketal A ₂ was added to low-sulfur gas oil (S=0.04%) so as to be 50 ppm, and the friction coefficient at 25°C was measured. The results are listed in Table 11.

As can be seen from Table 11, the friction coefficient of the product 22 of the present invention to which the cyclic ketal _A2 is added is smaller than that of the comparative product 5 without addition, and is also lower than that of light oil (comparative product 6) with a sulfur concentration of 0.2%. Low, indicating excellent lubricity.

Table 11 coefficient of friction Product of the present invention 22 0.164 Comparative product 5 0.328 Comparative product 6 0.304

Example 12

In order to examine the cyclic ketals A ₂ , D ₂ , F ₂ , I ₂ , K, L ₂ , M used in the products of the present invention obtained in the preparation examples and the oil b (polyalkylene glycol ) for electrical insulation, and the specific permittivity at 25° C. was measured in accordance with JISC-2101. The results are listed in Table 12.

It can be seen from Table 12 that the products of the present invention have low specific permittivity and good electrical insulation.

In addition, compared with cyclic ketal F ₂ and cyclic acetal I ₂ containing one ether bond, the cyclic ketal A ₂ , D ₂ , K, M, and cyclic acetal L ₂ without an ether bond A low specific permittivity indicates excellent electrical insulation.

Table 12 oil species specific permittivity The oil used in the product of the present invention Cyclic Ketal A ₂ 2.92 Cyclic ketal D ₂ 2.78 Cyclic Ketal F ₂ 3.47 Cyclic acetal I ₂ 3.22 Cyclic ketal K 2.65 Cyclic acetal L ₂ 2.50 Cyclic ketal M 2.89 Oil for comparison b(polyalkylene glycol) 5.31

Synthetic Example 11.2: 3.4: 5.6-tri-O-(2-methylidene propylene) sorbitol (1) and 1.3: 2.4: 5.6-tri-O-(2-methylidene propylene) sorbitol Synthesis of a mixture of sugar alcohols (2)

In a 3-liter reaction vessel equipped with a thermometer, a reflux condenser, a Dean-Stark trap, a calcium chloride tube and a stirrer, add 450 g (2.470 mol) of D-sorbitol, 588 g (8.154 mol) of isobutylaldehyde, and p-toluene Sulfonic acid-hydrate 4.70g (0.0247mol) and petroleum ether (boiling point 30-60°C) 400ml. The temperature was raised while stirring, and the reaction was carried out at 40-65° C. for 15 hours, and the calculated amount of water was distilled off. After the reaction, cool to 60°C, add 5.24g (0.0494mol) of sodium carbonate, stir at 60°C for 30 minutes, add 100g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 100 g of saturated brine and evaporated to obtain 868.03 g of a crude mixture of title compounds (1) and (2). The mixture was distilled under reduced pressure to obtain 800.17 g of a mixture of the title compounds (1) and (2).

Yield 94.0%, boiling point 137～149 ℃/0.3～0.6mmHg, gas chromatography purity 99.0% (the mixture ratio of title compound (1)/(2) is 88/12 (weight ratio)), hydroxyl value 6.0mgKOH/ g (theoretical value 0).

Spectra of the mixture of title compounds (1), (2)

IR (NEAT, cm ^-1 ): 2972, 2936, 2884 (CH telescopic), 1476, 1406, 1368 (CH variable angle), 1194, 1106, 1038 (COC telescopic), 722 (CH ₂ swing)

¹ HNMR (CDCl ₃ , δppm):

0.58～1.49 (18H, multiple lines, -CH ₃ )

1.53～2.13 (3H, multiple lines, -CH(CH ₃ ) ₂ )

3.32～3.70, 4.50～4.97 (3H, multiple lines, (-O-) ₂ CH-)

3.70～4.50 (8H, multiple lines, -CH ₂ CHCHCHCHCH ₂ -)

From 1.0 g of the mixture of the title compounds (1) and (2), use preparative silica gel thin-layer chromatography with hexane/ethyl acetate = 9/1 as the developing solvent to obtain the title compounds with Rf values of 0.6 to 0.7, respectively. (1) 0.63 g, and 0.09 g of the title compound (2) having an Rf value of 0.5.

¹³ CNMR (CDCl ₃ , δppm) of the title compound (1): 107.7 to 109.1 indicates a five-membered ring acetal structure.

¹³ CNMR (CDCl ₃ , δppm) of the title compound (2): 107.7～109.1, 104.9 respectively represent the structure of five-membered ring acetal and six-membered ring acetal (the intensity ratio of the peak of 107.7～109.1 to the peak of 104.9 is 1 to 2).

Synthetic example 21.2:3.4:5.6-tri-O-(3,5,5-trimethylhexylidene)sorbitol (3) and 1.3:2.4:5.6-tri-O-(3,5,5- Synthesis of a mixture of trimethylhexylidene)sorbitol (4)

In a 3-liter reaction vessel equipped with a thermometer, reflux condenser, Dean-Stark trap, calcium chloride tube and stirrer, add D-sorbitol 170.76g (0.937mol), 3,5,5-trimethylhexyl Aldehyde 400g (2.812mol), p-toluenesulfonic acid monohydrate 1.78g (0.00936mol) and hexane 400ml. The temperature was raised while stirring, and the reaction was carried out at 79-81° C. for 8 hours, and the calculated amount of water was distilled off. After the reaction, cool to 70°C, add 1.99g (0.0188mol) of sodium carbonate for neutralization, stir at 70°C for 30 minutes, add 100g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 100 g of saturated brine and evaporated to obtain 529.51 g of a crude mixture of title compounds (3) and (4). This mixture is distilled under reduced pressure (boiling point 27～85°C/0.5～0.9mmHg) to remove the initial runoff, and the obtained residue 500.87g is dissolved in 500ml of hexane, and is decomposed by activated clay 25.04g (relative to the residue 5% by weight). It was filtered under pressure (PTFE, 0.2 μm), washed with hexane, and the hexane in the hexane solution was completely evaporated to obtain 501.14 g of a mixture of title compounds (3) and (4).

The yield was 96.4%, the purity by gas chromatography was 93.2% (the mixing ratio of the title compound (3)/(4) was 31/69 by weight), and the hydroxyl value was 27.2 mgKOH/g (theoretical value 0).

IR (NEAT, cm ^-1 ): 2960, 2908, 2876 (CH telescopic), 1476, 1414, 1396, 1368 (CH variable angle), 1132, 1098, 1042 (COC telescopic), 714 (CH ₂ swing)

¹ HNMR (CDCl ₃ , δppm):

0.77～1.40 (42H, multiple lines, -CH(CH ₃ )CH ₂ C(CH ₃ ) ₃ )

1.40～2.49 (9H, multiple lines, -CH ₂ CH(CH ₃ )CH ₂ C(CH ₃ ) ₃ )

3.88～3.68, 4.48～5.15 (3H, multiple lines, (-O-) ₂ CH-)

3.68～4.42 (8H, multiple lines, -CH ₂ CHCHCHCHCHCH ₂ -)

Synthesis Example 31.3: 2.4: 5. Synthesis of 6-tri-O-(1-methylidenepropylene)sorbitol (5)

In a 3-liter reactor equipped with a thermometer, reflux condenser, Dean-Stark trap, nitrogen pipe and stirrer, add 336.84g (1.849mol) of D-sorbitol and 800g (11.094mol) of methyl ethyl ketone 17.58 g (0.092 mol) of p-toluenesulfonic acid monohydrate and 200 ml of hexane. The temperature was raised while stirring, and the reaction was carried out at 69-79° C. for 8 hours, and the calculated amount of water was distilled off. After the reaction, cool to 60°C, add 19.6g (0.185mol) of sodium carbonate for neutralization, stir at 60°C for 30 minutes, add water 200g, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 200 g of saturated brine and evaporated to obtain 643.75 g of the crude title compound (5). This material was distilled under reduced pressure to obtain 606.71 g of the title compound (5).

The yield is 95.3%, the boiling point is 136-140° C./0.6 mmHg, the gas chromatography purity is 97.3%, and the hydroxyl value is 12.9 mgKOH/g (theoretical value 0).

Synthesis Example 4

Synthesis of 1.2:3.4:5.6-tri-O-(1-methylidenepropylene)sorbitol (5)

In a 2-liter reaction vessel equipped with a thermometer, a reflux condenser, a Dean-Stark trap, and a stirrer, add 168.4 g (0.93 mol) of D-sorbitol, 400 g (5.6 mol) of methyl ethyl ketone, and p-toluenesulfonate Acid-hydrate 8.8g (0.046mol) and hexane 100g. Under a nitrogen atmosphere, the temperature was raised while stirring, and the reaction was carried out at 65-72° C. for 7 hours, and the calculated amount of water was distilled off. After the reaction, cool to 60°C, add 9.8g (0.09mol) of sodium carbonate for neutralization, stir at 60°C for 30 minutes, add water 100g, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with saturated brine until neutral, then dried over anhydrous sodium sulfate, filtered and distilled off hexane to obtain 293.5 g of the crude title compound (5).

The crude yield is 92.2%, and the hydroxyl value is 18.0 mgKOH/g (theoretical value 0).

100 g of this product was dissolved in 100 ml of hexane, and purified by silica gel column chromatography. Fractions eluted at hexane/ethyl acetate=8/2 were collected and evaporated to obtain 95 g of the title compound (5).

The gas chromatography purity is 99.7%, and the hydroxyl value is 0 mgKOH/g (theoretical value 0).

IR (NEAT, cm ^-1 ): 2980, 2938, 2890 (CH telescopic), 1470, 1380 (CH variable angle), 1242, 1194, 1140, 1080 (COC telescopic), 717 (CH ₂ swing)

¹ HNMR (CDCl ₃ , δppm):

0.72～1.10 (9H, multiple lines, -CH ₂ CH ₃ )

1.10～1.48(9H, multiple lines, (-O-) ₂ C(CH ₃ )-)

1.48～1.90 (6H, multiple lines, -CH ₂ CH ₃ )

3.71～4.31 (8H, multiple lines, -CH ₂ CHCHCHCHCH ₂ -)

Synthesis Example 5

Synthesis of 1.2:3.4:5.6-tri-O-(1,3-dimethylbutylene)sorbitol (7):

In a 3-liter reaction vessel equipped with a thermometer, reflux condenser, Dean-Stark trap, calcium chloride tube and stirrer, 363.76 g (1.997 mol) of D-sorbitol and 1200 g (11.981 mol) of methyl isobutyl ketone were added. mol), p-toluenesulfonic acid-hydrate 18.99g (0.0998mol and 300ml of hexane. Stir while heating up, carry out 23 hours reaction at 93～98 ℃, evaporate the water of calculated amount. Cool to 60 ℃ after reaction finishes, add Neutralize with 21.16g (0.1996mol) of sodium carbonate, stir at 60°C for 30 minutes, add 200g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, wash with 200g of saturated saline and evaporate to obtain the crude title Compound (7) 736.65g. This material is distilled under reduced pressure (30.5～141 ℃/2～0.7mmHg of boiling point), removes the initial run, and the residue 657.62g that obtains passes through activated clay (relative to residue 5% weight) pressure filtration ( PTFE, 0.2 μm), to obtain 637.44 g of the title compound (7).

The yield was 74.5%, the purity by gas chromatography was 93.1%, and the hydroxyl value was 34.3 mgKOH/g (theoretical value 0).

Synthesis Example 6

Synthesis of 1.2:3.4:5.6-tri-O-(1,3-dimethylbutylene)sorbitol (7):

In a 1-liter reaction vessel equipped with a thermometer, a reflux condenser, a Dean-Stark trap, a nitrogen pipe and a stirrer, 127.5 g (0.7 mol) of D-sorbitol and 420.7 g (4.2 mol) of methyl isobutyl ketone were added. mol), p-toluenesulfonic acid-hydrate 6.7g (0.035mol) and toluene 100g. Under a nitrogen flow, the temperature was raised while stirring, and a dehydration reaction under reduced pressure was carried out at 92° C. for 8 hours. After the reaction, cool to 60°C, add 10.6g (0.1mol) of sodium carbonate to neutralize, stir at 60°C for 30 minutes, add 60g of water, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with saturated brine until neutral. Toluene was distilled off to obtain 247.2 g of the crude title compound (7).

The crude yield is 82.4%, and the hydroxyl value is 33.2 mgKOH/g (theoretical value 0).

100 g of this product was dissolved in 100 ml of hexane, and purified by silica gel column chromatography. Fractions eluted at hexane/ethyl acetate=8/2 were collected and evaporated to obtain 90 g of the title compound (7).

The gas chromatography purity is 99.4%, and the hydroxyl value is 0 mgKOH/g (theoretical value 0).

IR (NEAT, cm ^-1 ): 2984, 2956, 2876 (CH telescopic), 1470, 1378 (CH variable angle), 1242, 1186, 1148, 1096 (COC telescopic), 718 (CH ₂ swing)

¹ HNMR (CDCl ₃ , δppm):

0.78～1.10 (18H, multiple lines, -CH ₂ CH(CH ₃ ) ₂ )

1.22～1.47(9H, multiple lines, (-O-) ₂ C(CH ₃ )-)

1.47～1.68 (6H, multiple lines, -CH ₂ CH(CH ₃ ) ₂ )

1.68～2.03 (3H, multiple lines, -CH ₂ CH(CH ₃ ) ₂ )

3.71～4.38 (8H, multiple lines, -CH ₂ CHCHCHCHCHCH ₂ -)

Synthesis Example 7

Synthesis of 1.2:3.4:5.6-tri-O-(1-methylidenepropylene)mannitol (17):

In a 3-liter reaction vessel equipped with a thermometer, a reflux condenser, a Dean-Stark trap and a stirrer, add 336.84 g (1.849 mol) of D-mannitol, 800.0 g (11.094 mol) of methyl ethyl ketone, and p-toluene Sulfonic acid monohydrate 17.58g (0.092mol) and hexane 200ml. Under a nitrogen atmosphere, the temperature was raised while stirring, and the reaction was carried out at 68-76° C. for 10 hours, and the calculated amount of water was distilled off. After the reaction, cool to 60°C, add 19.6g (0.185mol) of sodium carbonate to neutralize, stir at 60°C for 30 minutes, add water 200g, stir at 60°C for 30 minutes, and let stand to separate layers. After removing the lower layer, it was washed with 200 g of saturated brine and evaporated to obtain 639.06 g of the crude title compound (17). The product was partially purified by distillation under reduced pressure to obtain 605.76 g of the title compound (17) (95.1% yield).

The boiling point is 136-140°C/0.3mmHg, the gas chromatography purity is 94.2%, and the hydroxyl value is 12.7mgKOH/g (theoretical value 0).

The dynamic viscosity at 40°C is 37.65mm ² /s, and the dynamic viscosity at 100°C is 3.726mm ² /s.

150 g of this product was dissolved in 150 ml of hexane, and purified by silica gel column chromatography. Fractions eluted at hexane/ethyl acetate=8/2 were collected and evaporated to obtain 135 g of the title compound (17).

The gas chromatography purity is 99.6%, and the hydroxyl value is 0.2 mgKOH/g (theoretical value 0).

IR (NEAT, cm ^-1 ): 2986, 2944, 2890 (CH telescopic), 1467, 1377 (CH variable angle), 1242, 1191, 1137, 1077 (COC telescopic), 708 (CH ₂ swing)

¹ HNMR (CDCl ₃ , δppm):

0.72～1.13 (9H, multiple lines, -CH ₂ CH ₃ )

1.13～1.50 (9H, multiple lines, (-O-) ₂ C(CH ₃ )-)

1.50～1.90 (6H, multiple lines, -CH ₂ CH ₃ )

3.88～4.37 (8H, multiple lines, -CH ₂ CHCHCHCHCH ₂ -)

Test example 1

The 40°C and 100°C dynamic viscosities (JISK-2283) and pour points (JISK-2269) of the cyclic acetals of the present invention obtained in the synthesis examples were measured. The results are listed in Table 13.

Table 13 compound Viscosity at 40°C (mm ² /s) Viscosity at 100℃(mm ² /s) Pour point (°C) Compound of the present invention (1) and mixture of (2) (synthesized with Synthesis Example 1) 167.8 5.81 -25.0 The compound of the present invention (3) and the mixture of (4) (synthesis with Synthesis Example 2) 394.6 15.5 <-20.0 Compound of the present invention (5) (synthesized with Synthesis Example 4) 63.1 4.54 -32.5 Compound of the present invention (7) (synthesized with Synthesis Example 6) 53.9 5.36 -27.5 Compound of the present invention (17) (synthesized with Synthesis Example 7) 35.2 3.63 -45.0 Comparative product 1 (naphthenic oil: SUNISO 4GS, manufactured by Japan Sun Petroleum Co., Ltd.) 55.5 5.87 -40.0 Comparative product 2 (polyalkylene glycol: Newpol LB-285, manufactured by Sanyo Chemical Industry Co., Ltd.) 60.3 11.4 -40.0 Comparative product 3 (tris(hydroxymethyl)propane/2-methylhexanoic acid, 2-ethylpentanoic acid, 3,5,5-trimethylhexanoate) 31.4 5.31 <-45.0 Comparative product 4 (pentaerythritol/2-ethylhexanoic acid, 3,5,5-trimethylhexanoate) 62.2 7.99 <45.0

Test example 2

The compatibility of the cyclic acetals of the present invention obtained in the synthesis examples and the comparative product with 1,1,1,2-tetrafluoroethane (HFC-134a) was measured. That is, when the measured oil concentration is 10% (volume), 20% (volume), 30% (volume), 40% (volume), and 50% (volume), for 1,1,1,2-tetrafluoroethylene Two-phase separation temperature at low temperature of alkane. The results are listed in Table 14.

Table 14 compound Cryogenic separation temperature (°C) 10% (volume) 20% (volume) 30% (volume) 40% (volume) 50% (volume) Compound of the present invention (1) and mixture of (2) (synthesized with Synthesis Example 1) -62 -44 -39 -39 -42 Compound of the present invention (5) (synthesized with Synthesis Example 4) <-70 <-70 <-70 <-70 <-70 Compound of the present invention (7) (synthesized with Synthesis Example 6) -17 -1 5 4.5 2 Compound of the present invention (17) (synthesized with Synthesis Example 7) -46 -38 -30 -27 -28 Comparative product 1 (naphthenic oil: SUNISO 4GS, manufactured by Japan Sun Petroleum Co., Ltd.) >20 >20 >20 >20 >20

As can be seen from Table 14, the compatibility of the product of the present invention is superior to that of the comparative product.

Test example 3

The 25 degreeC volume resistivity (measured according to JISC-2101) of the cyclic acetal of this invention obtained in the synthesis example and a comparative product was measured. The results are listed in Table 15.

Table 15 compound Volume resistivity (Ω.cm) Compound of the present invention (1) and mixture of (2) (synthesized with Synthesis Example 1) 3.6×10 ¹⁴ Compound of the present invention (5) (synthesized with Synthesis Example 4) 9.4×10 ¹⁵ Compound of the present invention (7) (synthesized with Synthesis Example 6) 5.8×10 ¹⁵ Compound of the present invention (17) (synthesized with Synthesis Example 7) 3.9×10 ¹⁵ Comparative product 2 (polyalkylene glycol: Newpol LB-285, manufactured by Sanyo Chemical Industry Co., Ltd.) 7.8×10 ¹¹

As can be seen from Table 15, the volume resistivity of the product of the present invention is better than that of the comparative product.

Test example 4

The composition of the cyclic acetals of the present invention and 1,1,1,2-tetrafluoroethane (HFC-134a) obtained in the synthesis example and the ester and 1,1,1,2-tetrafluoro The composition of ethane (HFC-134a) was tested for its attrition resistance by the Falex test.

Heat 100ml of oil to 80°C, feed 1,1,1,2-tetrafluoroethane (HFC-134a) at 101 per hour, run for 4 hours under a load of 150(1b), and measure the V slider after operation (block) and pin (pin) wear. The results are listed in Table 16.

As can be seen from Table 16, the wear amount of the products of the present invention is very small, indicating excellent wear resistance.

Table 16 compound Abrasion (mg) Compound of the present invention (1) and mixture of (2) (synthesized with Synthesis Example 1) 1.5 Compound of the present invention (5) (synthesized with Synthesis Example 3) 3.7 Comparative product 3 (tris(hydroxymethyl)propane/2-methylhexanoic acid, 2-ethylpentanoic acid, 3,5,5-trimethylhexanoate) 16.4 Comparative product 4 (pentaerythritol/2-ethylhexanoic acid, 3,5,5-trimethylhexanoate) 8.1

Possibility of industrial use

The present invention provides a synthetic lubricating oil that is excellent in thermal stability and oxidation stability, does not generate carboxylic acid due to hydrolysis, has low hygroscopicity, and is inexpensive. In addition, such a synthetic lubricating oil formulated with hydrofluorocarbons can provide a low-cost refrigerator refrigerant composition that has excellent electrical insulation and hygroscopicity, does not generate carboxylic acid due to hydrolysis. Furthermore, according to the present invention, novel cyclic acetals usable as synthetic lubricating oils are obtained in high yield and high purity from inexpensive raw materials by a simple method.

Claims (16)

1. ucon oil, it is characterized in that containing cyclic ketal or cyclic acetal, described cyclic ketal or cyclic acetal from one or more more than 4 yuan～(comprise 4 yuan and 10 yuan) below 10 yuan, first number is carbonyl compound shown in even polyvalent alcohol and one or more general formulas (I) or its active derivative ketal or acetal obtain R in the formula ¹Straight chain, side chain or the cyclic alkyl of expression hydrogen atom or 1～18 carbon atom, R ²Straight chain, side chain or the cyclic alkyl of 1～18 carbon atom of expression; Or R ¹And R ²Lump together the alkylidene group of 2～36 carbon atoms of expression.

2. ucon oil, it is characterized in that containing cyclic ketal or cyclic acetal, described cyclic ketal or cyclic acetal from one or more more than 4 yuan～(comprise 4 yuan and 8 yuan) below 8 yuan, first number is carbonyl compound shown in even polyvalent alcohol and one or more general formulas (II) or its active derivative ketal or acetal obtain R in the formula ³Straight chain, side chain or the cyclic alkyl of expression hydrogen atom or 1～12 carbon atom, R ⁴Straight chain, side chain or the cyclic alkyl of 1～12 carbon atom of expression; Or R ³And R ⁴Lump together the alkylidene group of 2～13 carbon atoms of expression; R ³And R ⁴The total carbonatoms be 1～13.

3. claim 1 or 2 described ucon oils, wherein polyvalent alcohol does not have ehter bond.

4. claim 1 or 2 described ucon oils, wherein polyvalent alcohol has an ehter bond.

5. claim 3 or 4 described ucon oils, wherein cyclic ketal or cyclic acetal contain 1,3-dioxolane structure and/or 1,3-diox structure.

6. any one described ucon oil in the claim 3～5, it is characterized in that containing cyclic ketal or cyclic acetal, described cyclic ketal or cyclic acetal are to obtain from the radical of saturated aliphatic of 4 yuan or 6 yuan, 4～25 carbon atoms alcohol and carbonyl compound shown in one or more general formulas (II) or its active derivative ketal or acetal.

7. ucon oil, it is characterized in that containing one or more formulas (IIIa), (IIIb), (IVa) or (IVb) shown in cyclic ketal or cyclic acetal,

R in the formula ³Straight chain, side chain or the cyclic alkyl of expression hydrogen atom or 1～12 carbon atom, R ⁴Straight chain, side chain or the cyclic alkyl of 1～12 carbon atom of expression; Or R ³And R ⁴Lump together the alkylidene group of 2～13 carbon atoms of expression; R ³And R ⁴The total carbonatoms be 1～13.

8. ucon oil, it is characterized in that containing one or more formula V or (VI) shown in cyclic ketal or cyclic acetal,

R in the formula ³Straight chain, side chain or the cyclic alkyl of expression hydrogen atom or 1～12 carbon atom, R ⁴Straight chain, side chain or the cyclic alkyl of 1～12 carbon atom of expression; Or R ³And R ⁴Lump together the alkylidene group of 2～13 carbon atoms of expression; R ³And R ⁴The total carbonatoms be 1～13.

9. refrigerator working fluid compositions wherein contains refrigerator oil and hydrogen fluorohydrocarbon that right requires any one described cyclic ketal among the 2-8 or cyclic acetal.

10. the described refrigerator working fluid compositions of claim 9 wherein contains hydrogen fluorohydrocarbon and refrigerator oil with hydrogen fluorohydrocarbon/refrigerator oil=50/1～1/20 (weight ratio).

11. following general formula (i) or (ii) shown in the cyclic acetal class, R in the formula ⁵The expression hydrogen atom, in this case, R ⁶The branched-chain alkyl of 3 carbon atoms of expression or the straight or branched alkyl of 4-21 carbon atom; Perhaps R ⁵The straight or branched alkyl of 1～21 carbon atom of expression, in this case, R ⁶The straight or branched alkyl of 2～21 carbon atoms of expression.

12. the described cyclic acetal class of claim 11, wherein R ⁵R during for hydrogen atom ⁶Be the branched-chain alkyl of 3 carbon atoms or the straight or branched alkyl of 4～12 carbon atoms, perhaps R ⁵R when being the straight or branched alkyl of 1～12 carbon atom ⁶It is the straight or branched alkyl of 2～12 carbon atoms.

13. the described cyclic acetal class of claim 11, wherein R ⁵R during for hydrogen atom ⁶Be the branched-chain alkyl of 3～12 carbon atoms, perhaps R ⁵R when being the straight or branched alkyl of 1～12 carbon atom ⁶It is the straight or branched alkyl of 2～12 carbon atoms.

14. any one described cyclic acetal class in the claim 11～13, wherein the hexavalent alcohol residue produces from Sorbitol Powder.

15. general formula (i) or (ii) shown in the preparation method of the described cyclic acetal class of claim 11, it is characterized in that making as shown in the formula hexavalent alcohol shown in (iii) and general formula (iv) shown in carbonyl compound or its active derivative (ketal or acetal) in the presence of acid catalyst, react

R in the formula ⁵The expression hydrogen atom, in this case, R ⁶The branched-chain alkyl of 3 carbon atoms of expression or the straight or branched alkyl of 4～21 carbon atoms; Perhaps R ⁵The straight or branched alkyl of 1～21 carbon atom of expression, in this case, R ⁶The straight or branched alkyl of 2～21 carbon atoms of expression.

16. the described preparation method of claim 15, wherein hexavalent alcohol is a Sorbitol Powder.