WO2001062694A1 - Process for preparation of 2,2,3,4,4,4-hexafluoro-1-butanol and use thereof - Google Patents

Abstract

A process for preparing 2,2,3,4,4,4-hexafluoro-1-butanol by reacting methanol with hexafluoropropene in the presence of a free radical reaction initiator, characterized by conducting the reaction while feeding hexafluoropropene.

Description

 Specification

 2, 2, 3, 4, 4, 4-hexafluoro-1

 Manufacturing process and its use

 Technical field

 The present invention relates to a process for producing 2,2,3,4,4,4_hexafluoro-1-butanol. 2,2,3,4,4,4-Hexafluoro-1-butanol produced by the production process is used as an intermediate or a solvent for various fluorine-containing functional materials. Particularly, CD-R and DVD-R It is used as a dye solvent for optical recording media typified by

 Background art

 Known methods for radical addition of hexafluoropropene and methanol include ultraviolet irradiation reaction, thermal reaction, and reaction with a radical initiator.

 In the UV irradiation reaction using a medium pressure mercury lamp, it takes 4 days for the reaction time to reach 90% conversion of hexafluoropropene (J. Fluorine Chem. 291, 28 (1985)) . The present inventors also carried out the reaction in the same manner using a mercury lamp. However, as shown in Comparative Example 1, the product was small with a reaction time of 16 hours, and it was thought that high productivity could not be expected.

 The product can be obtained by a simple thermal reaction but the efficiency is not good (U.S. Patent 3,927,129).

 As an efficient production method, there is a method using a radical initiator, and some methods for synthesizing 2,2,3,4,4,4-hexafluoro-1-butanol have been reported. However, since all of these are batch reactions in which the reaction is started by charging all of the raw materials and the initiator, the reaction heat becomes high temperature and high pressure, and it is difficult to control the reaction. In fact, these experiments are small and performed in small autoclaves (L Amer. Chem. Soc. 910, 77 (1955)) or in ampoules (J. Fluorine Chem. 291, 28 (1985)). I have.

In order to industrially produce 2,2,3,4,4,4-hexafluoro-1-butanol using this production method, a reactor of 10 L or more, especially 100 L or more will be used. However, in that case, the temperature and pressure rise due to the large heat of reaction, and control cannot be performed. Not only is it not good, but it is not desirable for safety such as explosion. In the method of J. Amer. Chem. So 910, 77 (1955) using a small autoclave as such an example, the conversion was 70 to 75%.

 As another production method, a method has been reported in which the radical initiator is decomposed at a temperature lower than the thermal decomposition temperature while irradiating ultraviolet rays to react 6F butanol at a low temperature (CS 268247). The advantage of this method is that the amount of generated radicals can be controlled by the irradiation amount of ultraviolet rays. In other words, there is a possibility that the reaction amount can be controlled by controlling the generated radical amount so that the reaction heat is equal to or less than the heat removal amount of the reaction apparatus. However, in the above document (CS 268247), the conversion of hexafluoropropene is as low as 59%, and a special pressure vessel equipped with a light irradiation device is required.

 As described above, there is a problem with each of the known production methods for industrially producing 2,2,3,4,4,4-hexafluoro-1-butanol. A detailed study of this reaction revealed that the greatest problem that had to be solved for the industrialization of this reaction was to remove heat generated by the progress of the reaction. The standard enthalpy of formation of this reaction estimated by the semi-empirical molecular orbital method (AMI method) is as large as _95KJZmol (-23Kc a 1 / mo 1). In addition, since the decomposition rate of the initiator increases as the temperature rises, if the reaction temperature rises once, there is a risk that the decomposition of the initiator is promoted and the reaction further proceeds, leading to a runaway reaction. Therefore, controlling the heat of reaction to be less than the heat removal capacity of the reactor is essential for the industrial production of 2,2,3,4,4,4-hexafluoro-1-butanol.

 In fact, when the reaction was carried out by the batch method, a rapid temperature rise and pressure increase were observed after the reaction started. In Comparative Example 2, it took only about 1 minute to raise the temperature from 100 ° C to 150 ° C. The radical chain reaction proceeded at once until hexafluoropropene was consumed. Furthermore, it was clarified that when the crude product of the batch reaction was purified by distillation, 2,2,3,4,4,4-hexafluoro-1-butanol was lost when removing impurities.

It is an object of the present invention to provide an industrially safe, inexpensive and feasible process for the production of 2,2,3,4,4,4-hexafluoro-1-butanol. Disclosure of the invention

 As a result of studying this reaction, the present inventors have found that the amount of heat generated by reaction heat can be reduced by supplying hexafluoropropene as a raw material during the reaction without charging the entire amount from the beginning. Was. Furthermore, by controlling the feed rate of hexafluoropropene, it was found that the calorific value could be kept below the heat removal capability of the reactor, and stable production could be achieved.

 Furthermore, when the amount of hexafluoropropene supplied was controlled, almost all of the hexafluoropropene introduced into the reactor was reacted, and the conversion was found to have an advantage of 90% or more.

 The present invention relates to the following items 1 to 11.

Item 1. Reacting methanol and hexafluoropropene in the presence of a radical initiator 2,2,3,4,4,4-hexafluoro-1-butanol 2,2,3,4,4,4-Hexafluoro-1-butanol production process, characterized in that the reaction is carried out while supplying water. Item 2. The production process according to Item 1, wherein the reaction is performed while hexafluoropropene is continuously supplied.

Item 3. The production process according to Item 1, wherein an initiator that generates an alkoxy radical as a decomposition product is used as a radical initiator.

Item 4. The method according to Item 1, wherein the radical initiator is selected from the group consisting of t-butyl 2-ethyl perhexanoate, di-n-propyl percarbonate, diisopropyl diapercarbonate and t-butyl peroxycarbonyl isopropyl carbonate. Manufacturing process.

Item 5. The process according to Item 1, wherein the reaction is started at a temperature lower than a temperature at which the half-life of the radical initiator is 10 hours.

Item 6. Moisture from 2,2,3,4,4,4-hexafluoro-1-butanol containing water with 2,2,3,4,4,4-hexafluoro-1-butanol A method of purifying 2,2,3,4,4,4-hexafluoro-1-butanol by removing it as the lowest azeotropic composition.

Item 7. After cooling the lowest azeotropic composition of water and 2,2,3,4,4,4-hexafluoro-1-butanol, liquid separation is performed, and the lower layer 2,2,3,4,4,4,1 is separated. Hexafluo Dehydration and purification of raw 1-butanol by the method described in Section 6, 2, 2, 3, 4, 4, and 4-hexafluoro-1-butanol.

Item 8. Including the step of removing water from 2,2,3,4,4,4-hexafluoro-1-butanol containing water with a dehydrating agent Go to 2,2,3,4,4,4-1 Kisafuro 1-Purification method for bushnool.

Item 9. The purification method according to Item 8, wherein the dehydrating agent is at least one selected from the group consisting of calcium chloride, zeolite, magnesium sulfate, and metal carbonate.

Item 10. Hydrocarbon-containing 2,2,3,4,4,4-hexafluoro-1-hydrobutanol is used to convert 2,2,3,4,4,4-hexafluoro-1-butanol 2,2,3,4,4,4_ Hexafluoro-1-butanol purification process including the step of removing as the lowest azeotropic composition with.

Item 1 1. A laser on a substrate manufactured using 2,2,3,4,4,4_hexafluoro-1-butanol manufactured by the process described in any of Items 1 to 10. An information recording medium provided with a recording layer on which information can be written and read out by Z or Z.

In the production process of the present invention, "reacting while supplying hexafluoropropene" means that the amount of hexafluoropropene charged at the start of the reaction is 20 kg or less per 100 kg of methanol. Means 10 kg or less, and the pressure of hexafluoropropene in the reaction system is maintained at about 0.05 to 2 MPa. The supply of hexafluoropropene during the reaction may be continuous or intermittent. The reaction is carried out in the liquid phase using a pressure vessel. Normally, methanol and an initiator are charged in advance, and after heating to a predetermined temperature, xafluoropropene is supplied. At this time, if a portion of hexafluoropropene is charged in advance at the stage of starting the reaction, the start of the reaction can be observed by increasing the temperature or decreasing the pressure. If the initial charge is too large, the temperature rise will increase and the initiator will be lost, so the temperature rise is preferably suppressed to 10 ° C or less, more preferably 5 ° C or less. The temperature rise in this case can be estimated from the heat capacity specific to the reactor and the standard enthalpy of formation described above. For example, since the heat capacity of the reactor used in Example 4 is 6600000 JZK, the initial charge of hexafluoropropene 3 OKg is expected to increase the temperature of the reaction system by about 2.8 ° C. Piled up. Thus, the initial charge can be determined by calculating from the heat capacity of the reactor such that the temperature rise is 10 ° C. or less, more preferably 5 ° C. or less. As a guide, the amount of hexafluoropropene is set to 20 kg or less, more preferably 10 kg or less, based on 100 kg of the charged methanol.

 Hexafluoropropene supplied during the reaction may be supplied to the reactor in gaseous form, or may be supplied directly in liquid form to the reaction solution. The hexafluorop pen may be supplied intermittently or continuously, but the supply rate should be lower than the heat removal capacity of the reactor so that the reaction temperature does not rise rapidly. If the amount of heat removed from the reactor is known or can be measured, the calorific value should be less than that value. It is more preferable to set. For example, in Example 4, while the heat removal capacity of the reactor used was 7500 KJ / (actual measurement), the average charge rate of hexafluoropropene was 58.3 kgZh (a calorific value of 36 90 OKJ Zh). Hexafluoropropene was charged continuously and quantitatively during the process so that the amount of heat generated by the reaction and the amount of heat removed by brine were constant. These operations are performed for the purpose of stabilizing the reaction system, and are important points for industrial production.

 If the amount of heat removed from the reactor is unknown, it cannot be said unconditionally due to the specifications of the reactor.However, as a guide, 100 kg of methanol is used at a dose of 20 kgZh or less for hexafluoropropene, It is preferable to control the temperature to ggZh or less.

 The methanol used in the reaction is preferably used in an excess amount (for example, about 3 to 10 mol per mol of hexafluoropropene) in order to improve the conversion of the more expensive hexafluoropropene. .

The type of radical initiator is not particularly limited, and a radical initiator that does not generate a hydroxyl radical (eg, benzoyl peroxide) may be used. However, a hydrogen atom is extracted from methanol to form a hydroxymethyl radical ('CH20H ) Is preferably used. Alkoxy radicals are examples of radicals having a high hydrogen atom abstracting ability. Suitable initiators among initiators that decompose and generate alkoxy radicals, for example, t-butyl 2-ethyl perhexanoate, dicarbonate —Propyl, Diisopropyl percarbonate (Peryl IPP), Carbonate t-petit Luparoxyisopropyl can be selected. For example, with Paloyl IPP, more than 50 moles of the product can be obtained per mole of initiator, but when the reaction is carried out using benzoylperoxide while supplying hexafluoropropene, the benzoylperoxide can be obtained. Only 11 moles of product were obtained per mole of oxide (Example 5).

 The amount of the radical initiator is not fixed depending on the type of the initiator used and the reaction conditions, but is based on the amount of the product 2,2,3,4,4,4,1-hexafluoro-1-butanol. About 1 to 10 mol% is used.

 The reaction temperature is not particularly limited, and the reaction can be carried out at various temperatures depending on the initiator used. However, in the early stage of the reaction, it is preferable to start at a temperature lower than the temperature at which the half-life of the initiator becomes 10 hours so that the decomposition reaction of the initiator does not proceed at once. The reaction temperature may be constant, but it is preferable to gradually raise the reaction temperature after the start of the reaction in order to maintain the concentration of radicals generated in the reaction system.

 For example, when Perbutyl II (half-life was 10 hours at 72 ° C) was used, the reaction was started at 48 ° C, and the temperature was raised to 75 ° C in 7 hours (Example 1). In addition, when Perloy NPP (half-life was 10 hours at 40 ° C) was used, the reaction was started at 29 ° C, and the temperature was raised to 41 ° C in 9 hours (Example 4). As described above, in the examples, the reaction was started at a temperature lower than the temperature at which the half life was 10 hours.

 The reaction pressure is preferably at least 0.1 MPa, more preferably at least 0.3 MPa so that hexafluoropropene can be dissolved in the reaction solution. When the vapor pressure of hexafluoropropene is lower than the reaction pressure, hexafluoropropene is supplied at a high pressure using a pump or a vaporizer. Although there is no particular upper limit for the pressure, a pressure of about 2 MPa is preferable for controlling the reaction.

 The initiator may be added during the reaction without adding the whole amount from the beginning. After completion of the reaction, the reaction may be carried out by adding a new initiator after degassing and cooling.

In this reaction, 2,2,3,4,4,4-hexafluoro-1-butanol produces the structural isomer 2-difluoromethyl-2,3,3,3-tetrafluoropropanol as a by-product. The amount of by-products tends to increase as the reaction temperature increases, and it is difficult to separate these two isomers by distillation. In fact, when the separation of the reaction solution obtained in Example 2 was attempted in a 30-stage Oldershaw rectification column, methanol Was easily separated, but 2,2,3,4,4,4-hexafluoro-1-butanol and 2-difluoromethyl-1,2,3,3,3-tetrafluoropropanol were It could not be completely separated.

 The amount of by-produced 2-difluoromethyl_2,3,3,3-tetrafluoropropanol is related to the reaction temperature during production, and the main product, 2,2,3,4,4, 4 It is formed at a rate of about 1 to 3% based on 1-hexafluoro-1-butanol. Although it is difficult to completely separate these compounds as described above, they are particularly suitable for use as intermediates for various fluorine-containing functional materials and dye solvents for information recording media such as CD-R and DVD-R. Can be used as a mixture without substantial problems.

 Further investigation of the purification of 2,2,3,4,4,4-hexafluoro-1-butanol revealed that 2,2,3,4,4,4-hexafluoro-1-butanol was found to be water and hydrocarbons. And the lowest azeotropic composition, which is applied to azeotropic distillation to obtain 2,2,3,4,4,4_hexafluoro-1-butanol containing impurities.

It has been found that 2,3,4,4,4-hexafluoro-1-butanol can be separated and purified. At this time, 2,2-difluoromethyl-2,3,3,3-tetrafluoropropanol contained in 2,2,3,4,4,4_hexafluoro-1-butanol is 2,2,3 It showed the same behavior as 4,4,4_hexafluoro-1-butanol. In addition, 2,2,3,4,4,4_hexafluoro-1-butanol containing impurities is specifically:

 1. Manufactured using an initiator diluted with water, hydrocarbon, etc. as a stabilizer 2, 2,

3, 4, 4, 4

 2. 2,2,3,4,4,4-hexafluoro-1-butanol that has absorbed moisture in the air

 3. After use as a solvent, 2,2,3,4,4,4-hexafluoro-1-butanol can be mentioned.

2,2,3,4,4,4-Hexafluoro-1-butanol, which contains water as an impurity, is distilled, and first, water and 2,2,3,4,4,4_hexafluoro-1 The azeotropic composition of butanol is distilled off, and then the water-free 2,2,3,4,4,4-hexafluoro-1-butanol is the fluorinated alcohol with S as the main component. Therefore, a pure product without water can be obtained. At this time, the azeotropic temperature was 98 to 99 ° C at normal pressure, and the weight ratio of fluoroalcohol in the azeotropic composition was about 60 mass%.

 The azeotropic composition of water and 2,2,3,4,4,4-hexafluoro-1-benzol separates into two liquids when cooled below about 50 ° C. Approximately 5000 mass ppm of water is dissolved in the lower layer of 2,2,3,4,4,4-hexafluoro-1-butanol, which can be removed by repeated azeotropic distillation.

 The dissolved water may be removed using a dehydrating agent. As the dehydrating agent, those exhibiting neutrality or acidity when dispersed in water are preferred. Examples include calcium chloride, zeolite, and magnesium sulfate. In particular, in the case of dehydration to a trace amount of l O Omass ppm or less, it is preferable to dehydrate with zeolite after pre-dehydration.

 2,2,3,4,4,4-hexafluoro-1-butanol containing charcoal hydrogen as an impurity is also similar to hydrocarbons and 2,2,3,4,4,4-hexafluoro-1-butanol. The azeotropic composition of the alcohol is distilled off, and then the hydrocarbon-free 2,2,3,4,4,4-hexafluoro-1-butyl alcohol, which is the main component, is distilled off. A pure product containing no arsenic is obtained. In this case, examples of the hydrocarbon include cyclohexane, heptane, and hexane, but are not limited as long as it is a compound that forms a minimum azeotropic composition with 2,2,3,4,4,4-hexafluoro-1-butanol. .

 For example, 2,2,3,4,4,4-hexafluoro-1-butanol and cyclohexane are 2,2,3,4,4,4-hexafluoro-1-ol at normal pressure and azeotropic temperature of 75-77 ° C. One butanol produces an azeotropic composition of about 4 Omass%. 2,2,3,4,4,4-hexafluoro-1-butanol and heptane are 2,2,3,4,4,4-hexafluoro-1-butanol at azeotropic temperature 85-87 ° C under normal pressure. Produces an azeotropic composition of about 60 ma ss%.

 The azeotropic composition of hydrocarbon and 2,2,3,4,4,4-hexafluoro-1-butanol separates into two liquids when cooled below about 30 ° C. Hydrocarbons are dissolved in the lower layer of 2,2,3,4,4,4-hexafluoro-1-butanol, but can be removed by repeating azeotropic distillation.

2,2,3,4,4,4 Containing water and hydrocarbons simultaneously as impurities Distillation of Luolow 1-butanol distills the lowest azeotropic composition of 2,2,3,4,4,4-hexafluoro-1-butanol, and finally 2,2,

3,4,4,4-Hexafluoro-1-butanol is distilled off to obtain a pure product.

 For example, distilling 2,2,3,4,4,4-hexafluoro-1-butanol containing water and heptane, after distilling off water and heptane as an azeotropic composition, 2,2,

Only fluorinated alcohols containing 3,4,4,4-hexafluoro-1-butanol as the main component are obtained. In this distillation, when the azeotropic composition distilled out first is cooled, three liquids are separated. This suggests that the first fraction of the distillation had the lowest azeotrope of the three components. The heptane phase, the aqueous phase, and the 2,2,3,4,4,4-hexafluoro-1-butanol phase from the upper layer. Impurities are dissolved in the lower layer 2,2,3,4,4,4-hexafluoro-1-butanol, which can be removed by repeating azeotropic distillation.

 An information recording medium having a recording layer on which information can be written and / or read by a laser on a substrate can be obtained by the method of the present invention.

The dye is dissolved in a solvent containing 4,4-hexafluoro-1-butanol, preferably a fluorine-containing solvent containing 2,2,3,4,4,4-hexafluoro-1-butanol, and the resulting solution is placed on a substrate. It can be manufactured by forming a recording layer containing a dye according to a conventional method such as coating and drying. Examples of the dye include cyanine dyes, phthalocyanine dyes, pyrylium dyes, thiopyrylium dyes, squarylium dyes, azurenium dyes, indophenol dyes, indoline phosphorus dyes, triphenylmethane dyes, and quinone dyes. Dyes, aluminum dyes, diimmonium dyes, metal complex salt dyes, and the like. Examples of the substrate include plastic, glass, and ceramics such as polypropionate, polymethyl methacrylate, epoxy resin, amorphous polyolefin, polyester, and polychloride pinil. In addition, an undercoat layer may be provided between the recording layer and the substrate for the purpose of improving flatness, improving adhesive strength, preventing deterioration of the recording layer, and a protective layer may be provided on the recording layer. .

According to the present invention, the progress of the reaction can be controlled by the amount of hexafluoropropene which supplies the reaction. On the other hand, according to the conventional batch method, the total amount of hexafluoropropene The reaction temperature and reaction pressure rise rapidly because the amount is charged into the reactor from the beginning and the reaction is performed. Therefore, the present invention has the following advantages as compared with the conventional batch method.

 1. Since the reaction can be performed at a lower temperature compared to the batch reaction, the reaction can be performed in a reactor having lower heat resistance performance;

 2. Since the reaction can be performed at a lower pressure compared to the batch reaction, the reaction can be performed in a reactor having a lower pressure resistance performance;

 3. Conversion can be increased by limiting the amount of hexafluoropropene supplied;

 4. Since the progress of the reaction can be controlled by the amount of hexafluoropropene supplied, it can be carried out safely because there is no sudden rise in temperature or pressure.

 Further, according to the present invention, an information recording medium (such as an optical disc such as a CD-R or DVD-R) having a recording layer capable of writing and Z or reading information by a laser on a substrate, a film 2,2,3,4,4,4-hexafluoro-1-butanol suitable for the production of photoreceptors can be produced on a large scale and efficiently.

 BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, the present invention will be described specifically with reference to Examples.

Example 1: 1 L reaction

 400 g of methanol, 10 g of initiator (t-butyl 2-ethylperhexate; perbutyl O) and 40 g of initial amount of hexafluoropropene were sucked into a 1 L autoclave The temperature was gradually raised. The reaction was started at a reaction temperature of 48 ° C, and then heated at a reaction pressure of 0.5 MPa while hexafluoropropene was intermittently supplied. After about 7 hours, the reaction was completed when 277 g of hexafluoropropene was charged. At this time, the reaction temperature was 75 ° C. The unreacted hexafluoroprobene was recovered to be 27 g and was analyzed by gas chromatography to be 2,2,3,4,4,4,4-hexafluoro-1-butanol and 2-difluorome as fluorine compounds. Chill 2,3,3,3-tetrafluoropropanol was produced. 90% conversion.

Example 2: 20 L reaction 5 kg of methanol was charged into a 20-liter autoclave with a jacket that was evacuated and kept at 20 ° C. 240 g of 50% di-n-propyl percarbonate and 1 kg of hexafluoropropene were charged therein as initiators. When the temperature was gradually raised while stirring, an exotherm was observed when the reaction temperature reached 30 ° C, and the reaction was started. Thereafter, hexafluoropropene was charged until the reaction pressure reached 0.3 MPa. Thereafter, hexafluoropropene was continuously charged so that the reaction pressure became 0.3 MPa. The reaction temperature was gradually raised, and when it reached 42 ° C after 10 hours, the supply of hexafluoropropene was stopped. Hexafluoropropene charge was 4.53k. The mixture was further heated and stirred for 1 hour to complete the reaction, and then cooled. After the reaction, 20 g of unreacted hexafluoropropene was recovered from the autoclave. Analysis of the reaction solution by gas chromatography showed that in addition to methanol and isopropanol derived from the initiator, the desired 2,2,3,4,4,4-hexafluoro-1-butanol and 2-difluoromethyl- 2,3,3,3-tetrafluoropropanol was detected. 2-Difluoromethyl-2,3,3,3-tetrafluoropropanol was obtained at 1.2% relative to 2,2,3,4,4,4-hexafluoro-1-butanol. The conversion was 99%.

Example 3: Distillation

 1 kg of the reaction solution synthesized in Example 2 was distilled in a 30-stage ordowsho type rectification column. After distilling off a fraction mainly composed of methanol, the desired 2,2,3,4,4,4-hexafluoro-1-butanol and 2-difluoromethyl-2,2

A fraction mainly containing a mixture with 3,3,3-tetrafluoropropanol was distilled out. 1 Collect fraction from 14 ° C to 118 ° C and add 2,2,3,4,4,4-hexafluoro-1-butanol to 2-difluoromethyl-2,3,3,3-tetraflur 460 g were obtained as a mixture with olopropanol. Also, 2, 2, 3, 4,

4,4-Hexafluoro-11-butanol could not be completely separated from 2-difluoromethyl-2,3,3,3-tetrafluoropropanol.

Example 4: 2 m ³ reaction

Maintaining the methanol 500 kg in feed 20 ° C to 2 m ³ pressure-resistant reactor following specifications. There is 50% di-n-propyl percarbonate (Paryl NPP) as an initiator 26 kg and 30 kg of hexafluropropene were charged. When the temperature was gradually increased while stirring, an exotherm was observed when the reaction temperature reached 29 ° C, and the reaction was started. Thereafter, hexafluoropropene was charged until the reaction pressure reached 0.44 MPa. Thereafter, hexafluoropropene was continuously charged so that the reaction pressure was 0.41 to 0.45 MPa. The reaction temperature was gradually raised, and when it reached 41 ° C after 9 hours, the supply of hexafluoropropene was stopped. Hexafluoropropene charge was 525 kg. The mixture was further heated and stirred for 4 hours to complete the reaction, and then cooled. Analysis of the reaction solution by gas chromatography showed that in addition to methanol and isopropanol derived from the initiator, the desired 2,2,3,4,4,4-hexafluoro- 1-butanol and 2-difluoromethyl-2, 3,3,3-tetrafluoropropanol was detected. 2-Difluoromethyl-2,3,3,3-tetrafluoropropanol was obtained at 1.2% relative to 2,2,3,4,4,4-hexafluoro-1-butanol. The conversion was over 99%.

Reactor specifications

 Withstand pressure (MPa): 5

 Material: s s 316 L

 Heat removal (K J / h): 75000

 Heat capacity (JZK): 6600000

 Average charging speed: 58.3 kg / h (3690 OK JZh as calorific value). Example 5: 1 L reaction (benzoyl peroxide)

200 g of methanol, 7.5 g of initiator (75 peroxyl benzoyl (water-containing product)) and 7 g of hexafluoropropene as initial charge amount were sucked into a 1 L autoclave, and gradually increased. Let warm. After 48 ° C, the reaction started, and the temperature was raised to 75 ° C while the hexafluoropropene was intermittently supplied at a reaction pressure of 0.5 MPa. Five hours later, the reaction was terminated when 61 g of hexafluoropropene had been charged. Unreacted hexafluoropropene was recovered to be 18 g, and was analyzed by gas chromatography to find 2,2,3,4,4,4-hexafluoro1--1-butanol as a fluorine compound. 2-Difluoromethyl-2,3,3,3-tetrafluoropropanol was formed. Conversion rate 70%. Comparative Example 1: Light irradiation reaction with a mercury lamp

 500 ml of methanol was charged into a 1000 ml flask for light irradiation, and light was irradiated with a high-pressure mercury lamp while flowing hexafluoropropene (about 10 OmlZ). After 17 hours irradiation, analysis by gas chromatography revealed that about 23 g of 6 FBuOH was produced. Hexafluoropropene conversion was 2.7%. Comparative Example 2: Batch reaction

1152 g of methanol, 22.5 g of an initiator (75% benzoyl peroxide (water-containing product)) and 600 g of hexafluoropropene were sucked into a 3 L autoclave, and the temperature was gradually raised. The exotherm increased at a reaction temperature of 80 ° C, and when it exceeded 100 ° C, the exotherm suddenly increased to 150 ° C. The pressure at that time reached up to about 2 MPa, only requiring Do ^ was violent reaction 1 50 ° about 1 minute to warm to C from 100 ^D C. After cooling to 100 ° C, it was kept at 100 for 1.5 hours. Hexafluoropropene was almost completely consumed, but analysis by gas chromatography revealed that impurities other than the target product were generated, and the selectivity was less than 90%.

Next, when this reaction solution was purified by distillation, the target product was lost when impurities were removed, and the recovery was 49%.

Claims

The scope of the claims  1. Methanol and hexafluoropropene are reacted in the presence of a radical initiator. In the 2,2,3,4,4,4-hexafluoro-1-butanol production process, hexafluoropropene is used. 2,2,3,4,4,4 -Hexafluoro-1-benzol production process, characterized in that the reaction is carried out while supplying hydrogen.  2. A process for producing 2,2,3,4,4,4-hexafluoro-1-benzol, which is characterized by reacting while supplying hexafluoropropene continuously.  3. The production process according to claim 1, wherein an initiator that generates an alkoxy radical as a decomposition product is used as a radical initiator.  4. The process of claim 1, wherein the radical initiator is selected from the group consisting of t-butyl 2-hexyl perhexanoate, di-n-propyl percarbonate, diisopropyl percarbonate, and t-butyl peroxyisopropyl carbonate. 5. The production process according to claim 1, wherein the reaction is started at a temperature lower than a temperature at which the half life of the radical initiator is 10 hours.  6. Moisture containing 2,2,3,4,4,4-hexafluoro-1-butanol is the lowest azeotropic composition of water with 2,2,3,4,4,4-hexafluoro-1-butanol. A method for purifying 2,2,3,4,4,4-hexafluoro-1-butanol by removing as a solvent.  7. After cooling down the lowest azeotropic composition of water and 2,2,3,4,4,4-hexafluoro-1-butanol, separate and separate into lower layers 2,2,3,4,4,4 A process for purifying 2,2,3,4,4,4_hexafluoro-1-butanol by dehydrating and purifying xafluoro-1-butanol by the method of claim 6. 8. 2,2,3,4,4,4-containing water containing 2,3,4,4,4-hexafluoro-1, including the step of removing water with a dehydrating agent Purification of xafluoro-1-butanol. 9. The purification method according to claim 8, wherein the dehydrating agent is at least one selected from the group consisting of salted calcium, zeolite, magnesium sulfate and metal carbonate. Law.  10. Conversion of hydrocarbons from 2,2,3,4,4,4-hexafluoro-1-butanol containing hydrocarbons to 2,2,3,4,4,4-hexafluoro-1-butanol A process for purifying 2,2,3,4,4,4-hexafluoro-1-butanol, comprising the step of removing as the lowest azeotropic composition.  11. A laser produced on a substrate, produced using 2,2,3,4,4,4-hexafluoro-1-benzol produced by the process according to any one of claims 1 to 10. An information recording medium provided with a recording layer on which information can be written and Z or readable.