WO2008047812A1 - Method for producing hydrophilic monomer - Google Patents

Abstract

Disclosed is a method for easily producing a crosslinkable hydroxyl group-containing (meth)acrylate-like compound at low cost by using a highly safe raw material. Specifically disclosed is a method for producing a hydrophilic monomer represented by the formula (4) below, which comprises a step for reacting a compound represented by the formula (1) below with a compound represented by the formula (2) below. (In the formulae, the symbols are as defined in the description.)

Description

 Specification

 Method for producing hydrophilic monomer

 Technical field

 [0001] The present invention relates to a method for producing a hydrophilic monomer having a polymerization-reactive acyloxy group such as a (meth) atalylooxy group at the end of an alkyl chain and a hydroxyl group in a side chain of the alkyl chain. Related.

 Background art

 [0002] In recent years, as represented by the following formula (A), the alkyl chain has a polymerization-reactive acyloxy group such as a (meth) atalylooxy group at the end of the alkyl chain, and a hydroxyl group in the side chain of the alkyl chain. Hydrophilic monomers (hereinafter such compounds are referred to as crosslinkable hydroxyl group-containing (meth) acrylate-like compounds), in particular erythritol dimetatalylate (EDMA), xylitol dimethacrylate (XDMA) and sorbitol. Dimetatalylate (SDMA) has become useful in applications such as ink materials, coating materials, gel materials, adhesive materials, especially dental adhesives.

 [0003] [Chemical 1]

 [Wherein, R represents a hydrogen atom or an aliphatic saturated hydrocarbon group, p is an integer of 1 or more, and q is an integer of 0 or more (particularly q = 0). }

[0005] Examples of a method for producing a crosslinkable hydroxyl group-containing (meth) acrylate-like compound include, for example, a patent document (Japanese Patent Laid-Open No. 49 110622 corresponding to US Pat. No. 3,950,399) and a non-patent document. The method described in the literature (International Journal of Polymeric Materials, 1997, 37, 1-14) is known. In the method described in the patent document, 1, 2-3, 4-diepoxy Tan and methacrylic acid are reacted. However, since this method uses 1,2-3,4-diepoxybutane, which is extremely toxic, there are problems in its industrial implementation.

[0006] Further, in the method described in the above-mentioned non-patent document, (Sat) -2,3-dihydroxy-1,4-dibromobutane and sodium methacrylate are reacted to obtain erythritol dimetatalylate. However, this method has a problem that (±) -2,3 dihydroxy 1,4 dibromobutane is very expensive. In addition, (±) -2,3 dihydroxy-1,4, a method based on a synthetic route for protecting the hydroxyl group of 1,4-dibromobutane is also disclosed, S, which requires three steps because it uses a protecting group. is there. Therefore, the production method is complicated and disadvantageous for industrial implementation.

 Disclosure of the invention

 [0007] In view of the above problems, the present invention provides a method capable of producing a bridging hydroxyl group-containing (meth) acrylate-like compound easily and inexpensively using a highly safe raw material. Is Mejiro-an.

 [0008] The present invention relates to the formula (1)

[0009] [Chemical 2]

[Wherein n represents an integer of 1 or more.]

 Compound represented by {Hereinafter also referred to as Compound (1). } Into the expression (2)

[0011] [Chemical 3]

[In the formula, R ¹ represents a hydrogen atom or an aliphatic hydrocarbon group having from 10 to 10 carbon atoms, X represents a halogen atom, or a formula (3)

[0013] [Chemical 4]

[Wherein, R ¹ has the same meaning as described above.]

 The group represented by these is shown. }

 The compound represented by {Hereinafter also referred to as the compound (2). }, Which comprises reacting with the formula (4) [0015] [Chemical 5]

(Wherein R ¹ is as defined above, m is an integer of 1 or more, k is an integer of 0 or more, and m + k = n, m The arrangement order of the unit having a hydroxyl group and the unit having k ester groups is arbitrary.

 (Hereinafter also referred to as hydrophilic monomer (4)). } Manufacturing method.

[0017] In the present invention, it is preferable that n is an integer of 2 to 4! /. k is preferably 0. R ¹ is preferably a hydrogen atom or a methyl group. X is preferably a chlorine atom or an aromatic atom.

[0018] During the reaction, the reaction temperature is preferably -30 ° C to 120 ° C. In addition, compound (1

) It is preferable to use 1 · 5 to k + 3 mol of the compound (2) with respect to 1 mol.

[0019] When k is 0, the production method of the present invention preferably further includes a step of treating the reaction mixture of the compound (1) and the compound (2) with a hydrocarbon compound. At this time, the hydrocarbon compound preferably has 5 to 18 carbon atoms. Further, the hydrocarbon compound is at least one selected from the group consisting of pentane, hexane, heptane, octane, cyclopentane, cyclohexylene, toluene, xylene and mesitylene. More preferred.

 [0020] According to the present invention, a crosslinkable hydroxyl group-containing (meth) acrylate-like compound can be produced inexpensively and easily using a highly safe raw material.

 BEST MODE FOR CARRYING OUT THE INVENTION

 [0021] In the production method of the present invention, compound (1) and compound (2) are used as starting materials.

 [0022] In the compound (1), n is an integer of 1 or more, the availability of raw materials, and the hydrophilic monomer (4) ink material and coating that are the final product of the production method of the present invention From the viewpoint of utility in applications such as materials, gel materials, adhesive materials, and particularly dental adhesives, an integer of 2 to 4 is preferable. Compound (1) may be a mixture of two or more compounds in which n is different within the above definition. Compound (1) can be produced according to a known method. Some are available as a commercial product, and in that case, a commercial product may be used.

In the compound (2), R ¹ is a hydrogen atom or an aliphatic hydrocarbon group having 1 to 10 carbon atoms. Examples of the aliphatic hydrocarbon group having from 10 to 10 carbon atoms include an alkyl group having 1 to 10 carbon atoms, an alkyl group having 2 to 10 carbon atoms, an alkenyl group having 10 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, and the like. . Examples of the alkyl group of carbon number;! To 10 may be linear, branched or cyclic. Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, cyclopropyl group, and butyl group. , Isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, pentynole group, cyclopentyl group, hexyl group, cyclohexyl group, octyl group, cyclooctyl group, decyl group and the like. Examples of the alkenyl group having 2 to 10 carbon atoms, which may be linear, branched or cyclic, include, but are not limited to, butyl, allyl, butur, hexenyl, otatur, and decenyl. Groups and the like. Examples of the alkynyl group having 2 to 10 carbon atoms, which may be linear, branched or cyclic, include an ethur group, a propynyl group, a butur group, a hexul group, an otatur group, a decynyl group, etc. Can be mentioned. When the hydrophilic monomer (4), which is the final product, is used for a dental adhesive or the like, radical polymerization is performed. Therefore, R ¹ is preferably a hydrogen atom or a methyl group from the viewpoint of radical polymerization reactivity of the final product. Compound (2) may be a mixture of two or more compounds wherein R ¹ is different within the above definition! /.

In the compound (2), X is a halogen atom or a group represented by the formula (3). Therefore Compound (2) is an acid halide compound or an acid anhydride. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. X is preferably a chlorine atom or a bromine atom from the viewpoint of reactivity and easy availability of raw materials.

 [0025] Compound (2) can be produced according to a known method. Some are available as commercial products, and in that case, commercial products may be used.

 [0026] The production method of the present invention includes a step of reacting compound (1) with compound (2) (reaction step). The reaction step can be performed, for example, by mixing the compound (1) with the compound (2) in the presence of a solvent and a basic compound. For mixing, compound (2) may be added to compound (1), and compound (1) may be added to compound (2)! /. The addition of compound (2) to compound (1) may be performed stepwise.

 [0027] The amount of compound (2) to be used is preferably 1 · 5 to k + 3 mol, more preferably 1.8 to k + 2.5 mol, relative to 1 mol of compound (1) (k is And is synonymous with k in the hydrophilic monomer (4), the same shall apply hereinafter). When the amount of the compound (2) used is less than 1.5 mol, the yield of the hydrophilic monomer (4) tends to decrease, and when it exceeds k + 3 mol, the side chain hydroxyl group of the compound (1) There is a possibility that a large amount of by-products that are all reacted with the compound (2) may be produced.

[0028] Solvents include N, N dimethylformamide (DMF), N, N dimethylacetamide, N methylpyrrolidone, acetonitrile, propionitryl, pyridine, 4-dimethylaminopyridine, quinoline, triethylamine, trimethylamine Nitrogen-containing compounds such as dimethylsulfoxide, sulfolane and other sulfur-containing compounds, jetyl ether, diisopropyl etherenole, di-butinoreethenole, tert-butinoremethinoleetenore, tetrahydrofuran, 1,4 di-dioxane, Ethers such as anisole, ethylene glycol dimethyl ether, diethylene glycol retino chinenoate ethere, triethyleneglycolino methino ree tenole, tetraethylene glycol dimethyl ether, dichloromethane, 1,2-dichloroethane, black Halogenated hydrocarbons such as form, hydrocarbons such as pentane, hexane, cyclohexane, heptane, octane, benzene, toluene, xylene, methyl acetate, ethyl acetate, isopropyl acetate, dimethyl carbonate, jetyl carbonate, ethylene Esters such as carbonate, 1-butyl-3-methyl-1H-imidazole tetrafluoroborate, 1-butyl-3-methyl-1H-imidazole hexafluorophosphate, 1-et It is possible to use ionic liquids such as rho-3-methyl-1H-imidazoletrifluoromethanesulfonate, among which DMF, pyridine, and dimethylsulfoxide are highly soluble in compound (1). Is preferable. These solvents may be used alone or in admixture of two or more. The amount of the solvent used is preferably <10 to 100000 parts by weight, more preferably <100 to 10,000 parts by weight, with respect to 100 parts by weight of the compound (1).

 [0029] The basic compounds include trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, diisopropylethylamine, pyridine, 2-methylpyridine, 3-methylpyridine, 4-methylpyridine, 4-dimethylamino. Pyridine, 2,6 Dimethylbilysine, 2,4,6 Trimethylolpyridine, Quinoline, Isoquinoline, 1,8 Diazabicyclo [4.3.0] Nonene-5 (DBN), 1,8 Diazabicyclo [5.4.0 ] Undecene 1-7 (DBU), lithium carbonate, sodium carbonate, potassium carbonate, sodium hydrogen carbonate sodium hydroxide, potassium hydroxide, lithium hydroxide, tetramethylammonium hydroxide, tetraptylammonium hydroxide, etc. Of these, of these, triethylamine, pyridine, 4-dimethylamine Pyridine are preferred. The amount of the basic compound used is preferably 1 · 5 to k + 10 mol, more preferably 2 to k + 5 mol, relative to 1 mol of the compound (1). These basic compounds may be used alone or in admixture of two or more. Further, these basic compounds may be used as a solvent.

 [0030] In order to prevent a polymerization reaction which is a side reaction, a small amount of a polymerization inhibitor may be added. Examples of polymerization inhibitors include hydroquinone, hydroquinone monomethyl ether (MEH Q), 2, 4 dimethyl-6 tert butyl hydroquinone, phenol, teconole, phenols such as tert-butylcatechol, phenothiazine, p-phenylenediamine, Amines such as diphenylamine, copper complexes such as copper dimethyldithiocarbamate, copper jetyldithiocarbamate, copper dibutyldithiocarbamate, inorganic copper compounds such as copper sulfate, copper oxide, copper chloride These may be used alone or in admixture of two or more.

[0031] The reaction temperature is -30 to 120 ° C force S, preferably -20 to 90 ° C. If the reaction temperature is within this range, the compound (2) has a particularly high rate of selective reaction with the terminal hydroxyl group out of the side chain and terminal hydroxyl groups of the compound (1). A polymerization reaction Is also suppressed.

 [0032] The reaction time may be appropriately determined based on the concentrations of the compounds (1) and (2), the reaction temperature, etc., but 0.;! To 120 hours is preferred 0.5 to 48 hours Is preferred.

 [0033] The hydrophilic monomer (4) can be isolated from the reaction mixture according to a conventional method (for example, concentration, column chromatography, etc.).

[0034] The hydrophilic monomer (4) obtained as described above is a hydrophilic monomer having a structure represented by the above formula (4). From the viewpoint of usefulness for ink materials, coating materials, gel materials, adhesive materials, especially dental adhesives, etc., the hydroxyl groups of the side chains are esterified! /, N! /, That is, the above formula (4) It is preferable that k = 0. R ¹ is preferably a hydrogen atom or a methyl group! /.

 [0035] The reaction mixture obtained in the above reaction step is a compound represented by the following formula (5) in which the side chain of the alkyl chain is not esterified (hereinafter also referred to as hydrophilic monomer (5)). } And a compound represented by the following formula (6) in which the side chain of the alkyl chain is esterified {hereinafter also referred to as compound (6). }. In the case where the hydrophilic monomer (5) {the hydrophilic monomer (4)} in which k = 0 in the above formula (4) is selectively obtained, the compound (1) and the compound (2 The step of treating the mixture with a hydrocarbon compound (purification step) may be performed.

 [0036] [Chemical 6]

[0037] [Chemical 7]

[0038] {式（5)および式（6)中、 R¹および nは、前記と同義であり、 m'は、 0以上の整数であ り、 k'は、 1以上の整数であり、かつ m' +k' =nであり、 m'個の水酸基を有する単位 と k'個のエステル基を有する単位の配列順序は、任意である。 }

[0038] {In Formula (5) and Formula (6), R ¹ and n are as defined above; m 'is an integer of 0 or more; k' is an integer of 1 or more; And m ′ + k ′ = n, and the arrangement order of the units having m ′ hydroxyl groups and the units having k ′ ester groups is arbitrary. }

 [0039] Since the side chain hydroxyl group is also esterified, the compound (6) has higher lipophilicity than the hydrophilic monomer (5). Therefore, for hydrocarbon compounds, the compound () is overwhelmingly more soluble than the hydrophilic monomer (5), so that the treatment allows the hydrophilic monomer (5) and The force S removes the compound ½) from the mixture of the compound ½) by dissolving it in the hydrocarbon compound.

 [0040] The hydrocarbon compound is liquid at the treatment temperature. Therefore, the number of carbon atoms of the hydrocarbon compound is 5 to 18; As the hydrocarbon compound, either aliphatic or aromatic can be used, and it may be a saturated compound or an unsaturated compound. Specific examples of the hydrocarbon compound include aliphatic saturated hydrocarbon compounds such as pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, heptazane, Octadecane, cyclopentane, cyclohexane, cycloheptane, cyclooctane and the like. Examples of the aliphatic unsaturated hydrocarbon compound include hexene, otaten, decene, and cyclohexagen. Examples of the aromatic hydrocarbon compound include benzene, toluene, xylene, mesitylene and the like. Among these, pentane, hexane, heptane, octane, cyclopentane, cyclohexane, low boiling point and easy removal from the hydrophilic monomer (5) are easy. Toluene, xylene and mesitylene are preferred. These hydrocarbon compounds can be used alone or in admixture of two or more.

[0041] Treating the mixture with a hydrocarbon compound refers to bringing the mixture into contact with the hydrocarbon compound so that the compound (6) is dissolved in the hydrocarbon compound. As a specific treatment method, only a hydrocarbon compound may be added to a mixture of the hydrophilic monomer (5) and the compound (6) and mixed and stirred, but water and hydrocarbons may be added to the mixture. A method of adding a compound and performing a liquid separation treatment may be simple. The amount of the hydrocarbon compound used is preferably 10 to 100000 parts by weight with respect to 100 parts by weight of the mixture of the hydrophilic monomer (5) and the compound (6). It is more preferably 50 to 10,000 parts by weight.

[0042] The treatment is preferably performed at 30 to 120 ° C, more preferably at 10 to 90 ° C.

 [0043] After the treatment with the hydrocarbon compound, the hydrophilic monomer (5) can be recovered according to a conventional method. For example, when water and a hydrocarbon compound are added to the above mixture for liquid separation treatment, the aqueous layer is separated from a hydrophobic solvent in which the hydrophilic monomer (5) is soluble (eg, ethyl acetate, diethyl acetate). The hydrophilic monomer (5) can be recovered by treating with isopropyl ether or the like and concentrating the hydrophobic solvent in which the hydrophilic monomer (5) is dissolved. The recovered hydrophilic monomer (5) can be further purified by recrystallization or the like.

 [0044] As described above, the production method of the present invention uses a highly safe raw material, and is an inexpensive and easy method and contains a crosslinkable hydroxyl group-containing (meth) acrylate with EDMA, XDMA, SDMA, etc. Like compound {Hydrophilic monomer (4)} and suitable for industrial production

[0045] In particular, in the production method of the present invention, when a purification step is performed in addition to the above reaction step, a hydrophilic group in which the side chain hydroxyl group of an alkyl chain such as EDMA, XDMA, or SDMA is not esterified. Monomer {hydrophilic monomer (5)} can be obtained with high purity. It should be noted that when the treatment with the above-mentioned hydrocarbon compound is not performed, the reaction mixture of compound (1) and compound (2) contains a by-product, and therefore, a hydrophilic monomer rather than the reaction mixture. Where it is difficult to directly crystallize (5), the purity of the hydrophilic monomer (5) can be improved by treating the reaction mixture with a hydrocarbon compound, which enables purification by recrystallization. It is. This facilitates industrial production of high-purity hydrophilic monomer (5).

[0046] The method of removing the compound (6) by treating the hydrophilic monomer (5) containing the compound (6) with a hydrocarbon compound, which is performed in the above purification step, is hydrophilic. Since the compound (6) can be easily and efficiently separated from the monomer (5), it is useful as a method for purifying the hydrophilic monomer (5).

[0047] Further, paying attention to the above purification step, a hydrophilic step including a step of obtaining a mixture of the hydrophilic monomer (5) and the compound (6) and a step of treating the mixture with a hydrocarbon compound. Monomer (5) This production method is also an inexpensive and easy method using a highly safe raw material and is useful. The step of obtaining a mixture of the hydrophilic monomer (5) and the compound (6) is not limited to the reaction step described above, but in the above formula (2), X is an OR ² group (R ² is a carbon number of 1 to A step of reacting the ester compound (20 hydrocarbon group) with the compound (1) may be performed.

 [0048] Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

 [0049] Example 1

 (Reaction process)

 A 500 mL three-necked flask, erythritol (50 · Og, 0.409 mol), MEHQ (30 mg), DMF (700 mL), and triethinoreamine (124.1 g, 1.23 mol) were added and stirred with a stirrer. Methacrylic acid chloride (93.6 grams, 0.895 mol) was added via a dropping funnel over a period of 2.5 hours while maintaining the reaction temperature at 10-10 ° C. During this time, a large amount of a slightly yellow white solid precipitated. After completion of the dropwise addition, the mixture was further stirred at 40 ° C for 1 hour. After allowing to cool to 23 ° C, the precipitated salt was removed by filtration, and the filtrate was concentrated with an evaporator. Concentration was terminated when almost no DMF fraction was obtained.

[0050] (Purification process)

 160 g of the concentrate was transferred to a separatory funnel, distilled water (400 mL) was added, and the hexane-insoluble matter was washed twice with hexane (400 mL). This washing operation was performed at 24-26 ° C. Distilled water (200mU and diisopropyl ether (IPE) (500mL) was collected in the water layer, the IPE layer was obtained, and extracted with 1 to 3 (3; 500111 and 6 times). When the IPE was distilled off with an evaporator A slightly viscous yellowish white solid was obtained, and the crystals were washed with a small amount (about 30 mL) of cold IPE and dried in vacuo at room temperature to obtain 49.0 g (0.190 mol, yield 46%) of white crystals. — As a result of NMR measurement, it was found that the hydroxyl group at the 1st and 4th positions of erythritol was esterified, and the HPLC purity was 96%.

 1H-NMR (270 MHz, CDC1): δ 6. 16 (d, 2H, CH =), 5. 62 (d, 2H, CH =), 4. 42-4. 40 (dd, 4H, CH), 3 87 (m, 2H, CH), 2. 94 (br, 2H, OH).

[0051] Example 2

The same reaction step as in Example 1 was performed, and in the purification step of Example 1, hexane was substituted. A similar operation was carried out except that cyclohexane was used. 64.0 g (0.248 mol, yield 60%) of erythritol dimethacrylate was obtained as white crystals.

[0052] Example 3

 (Reaction process)

 A 500 mL three-necked flask, erythritol (50 · Og, 0.409 mol), MEHQ (30 mg), pyridine (800 mL) and triethinoreamine (124.1 g, 1.23 mol) were added and stirred with a stirrer. Methacrylic acid chloride (93.6 grams, 0.895 mol) was added with a dropping funnel over a period of 2.5 hours while maintaining the reaction temperature between 10 and 0 ° C. During this time, a large amount of a slightly yellow white solid precipitated. After completion of the dropwise addition, the mixture was further stirred at 40 ° C for 1 hour. After allowing to cool to 23 ° C, the precipitated salt was removed by filtration, and the filtrate was concentrated by an evaporator. Concentration was complete when almost no pyridine distillate was obtained.

[0053] (Purification process)

 150 g of the concentrate was transferred to a separatory funnel, distilled water (400 mL) was added, and the hexane-insoluble matter was washed twice with hexane (400 mL). This washing operation was performed at 24-26 ° C. Distilled water (200mU and diisopropyl ether (IPE) (500mL) was collected in the water layer, the IPE layer was obtained, and extracted with 1 to 3 (3; 500111 and 6 times). When the IPE was distilled off with an evaporator A slightly viscous yellowish white solid was obtained, and the crystals were washed with a small amount (approximately 30 mL) of cold IPE and vacuum-dried at room temperature to obtain 42.6 g (0.165 mol, yield 40%). — As a result of NMR measurement, it was found that the hydroxyl group at the 1st and 4th positions of erythritol was esterified, and the HPLC purity was 96%.

[0054] Example 4

 The same reaction step as in Example 3 was performed, and the same operation was performed in the purification step of Example 3 except that cyclohexane was used instead of hexane. 58.7 g (0.227 mol, yield 55%) of erythritol dimethacrylate was obtained as white crystals.

[0055] Example 5

 (Reaction process)

500mL three-necked flask ί, xylitol (60. Og, 0. 394mol), MEHQ (30mg), pyridine (1200mL) and torutinoleamine (119.6g, 1.18mol) Stir in one. While maintaining the reaction temperature at 10 to 0 ° C., methacrylic acid chloride (86.6 gram, 0.850 mol) was added with a dropping funnel over 2.5 hours. During this time, a large amount of a slightly yellow white solid precipitated. After completion of the dropwise addition, the mixture was further stirred at 40 ° C for 1 hour. After allowing to cool to 23 ° C, the precipitated salt was removed by filtration, and the filtrate was concentrated with an evaporator. Concentration ended when the pyridine distillation was slightly slower.

[0056] (Purification process)

 135 g of the concentrate was transferred to a separatory funnel, distilled water (350 mL) was added, and cyclohexane (twice with 400 m U, and the cyclohexane insoluble matter was washed. This washing operation was performed at 24-26 ° C. Distilled water (200 mL) and IPE (500 mL) were added to the aqueous layer to obtain an IPE layer, which was further extracted with IPE (3 L; 500 mL x 6 times). A yellow-white solid was obtained, and 35.0 g (0.121 mol, yield 31%) of white crystals were obtained by washing the crystals with a small amount (approximately 40 mU of cold IPE and vacuum drying at room temperature). As a result, it was proved to be xylitol dimethacrylate in which the hydroxyl groups at the 1-position and 5-position of xylitol were esterified, and the HPLC purity was 95%.

[0057] Example 6

 (Reaction process)

 Sonorevi, Yoichi Nore (88. Og, 0.483 Monole), MEHQ (30 mg), DMF (1.3 B), and 卜 Letylamine (203 mL, 1.23 mol) are added to a 2 L 3-neck flask. The stirring was continued at room temperature. While maintaining the reaction temperature at 10 ° C. to 0 ° C., methacrylic acid chloride (107 g, 0.895 mol) was added with a dropping funnel over 2.5 hours. During this time, a large amount of a slightly yellowish solid precipitated. After completion of the dropwise addition of methacrylic acid chloride, the mixture was further stirred at 40 ° C for 1 hour. Thereafter, the mixture was allowed to cool to room temperature, the salt precipitated by filtration was removed, and the filtrate was further distilled off with an evaporator to obtain a concentrate.

[0058] (Purification process)

200 g of this concentrate was transferred to a separatory funnel and distilled water (500 mU was added. Toluene / hexane (volume ratio 9: 1) (300 mL) was added thereto, and the mixture was vigorously shaken to remove the organic layer. Washing with toluene / hexane (volume ratio 9: 1) (300 mL) was performed twice more, and this washing was performed at 24 to 26 ° C. From the remaining aqueous layer, ethyl acetate (300 mU) was used. The extraction operation was performed 5 times. Ethyl acetate was concentrated to about 10 mL with an evaporator, and IPE (10 mL) was added and stirred. Since the solid was precipitated when cooled to 20 ° C., the solid was separated by filtration and vacuum dried at room temperature to obtain 29.3 g (0.092 2 mol, yield 19%) of a white solid. As a result of NMR measurement, it was found to be sorbitol dimetatalylate in which the hydroxyl groups at positions 1 and 6 of sorbitol were esterified. The HPL C purity was 92%.

Industrial applicability

 The present invention is useful as a method for producing a crosslinkable hydroxyl group-containing (meth) acrylate-like compound mainly used for ink materials, coating materials, gel materials, adhesive materials, particularly dental adhesives, and the like. Also suitable for industrial production.

Claims

The scope of the claims  Formula (1)

(In the formula, n represents an integer of 1 or more.) A compound represented by formula (2) [Chemical 2]

{Wherein R ¹ represents a hydrogen atom or an aliphatic hydrocarbon group having 1 to 10 carbon atoms; and X represents a halogen atom or a formula (3) [Chemical 3

(Wherein R ¹ has the same meaning as described above.) The group represented by these is shown. } Comprising a step of reacting with a compound represented by formula (4): [Chemical 4]

(In the formula, R ¹ is as defined above, m is an integer of 1 or more, k is an integer of 0 or more, and m + k = n, and has m hydroxyl groups. The order of units and units having k ester groups is arbitrary.)  The manufacturing method of the hydrophilic monomer represented by these. [2] The production method according to claim 1, wherein n is an integer of 2 to 4. [3] The production method according to [1], wherein k is 0. 4. The production method according to claim 1, wherein R ¹ is a hydrogen atom or a methyl group.  5. The production method according to claim 1, wherein X is a chlorine atom or a bromine atom.  6. The production method according to claim 1, wherein the reaction temperature is -30 ° C to 120 ° C.  7. The production method according to claim 1, wherein 1.5 to k + 3 mol of the compound represented by the formula (2) is used with respect to 1 mol of the compound represented by the formula (1). [8] The production method according to claim 3, further comprising a step of treating the reaction mixture of the compound represented by the formula (1) and the compound represented by the formula (2) with a hydrocarbon compound. [9] The process according to claim 8, wherein the hydrocarbon compound has 5 to 18 carbon atoms. 10. The production method according to claim 8, wherein the hydrocarbon compound is at least one selected from the group consisting of pentane, hexane, heptane, octane, cyclopentane, hexane, toluene, xylene, and mesitylene.