JP2011251941A - Method for producing hydroxyalkyl (meth)acrylate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method that permits efficient production of a hydroxyalkyl (meth)acrylate of high purity without necessitating a troublesome purification step.SOLUTION: The production method for a hydroxyalkyl (meth)acrylate comprises (meth)acrylating a vinyl ether-containing alcohol by a transesterification method to obtain a vinyl ether-containing (meth)acrylate, carrying out a devinylation reaction in the presence of an acid catalyst and water, and subsequently carrying out a deacetalization reaction by further adding water.

Description

  The present invention relates to a method for producing a hydroxyalkyl (meth) acrylic acid ester using a vinyl ether-containing alcohol.

  As a method for producing a hydroxyalkyl (meth) acrylic acid ester, generally, after obtaining a diol, monoester or diester mixture from an alkanediol by an esterification reaction, only the monoester is extracted and separated. . Specifically, a method of reacting (meth) acrylic acid and alkanediol in the presence of a strong acid has been reported (for example, see Patent Document 1), but a by-product due to the strong acid is produced, resulting in a decrease in yield. There are disadvantages such as. As a method for solving this problem, there are various reports on transesterification reaction between alkanediol and (meth) acrylic acid ester (see, for example, Patent Documents 2 to 4). In addition, methods for efficiently extracting and purifying 4-hydroxybutyl (meth) acrylate (see, for example, Patent Documents 5 to 6) have been reported. However, in such esterification reaction from alkanediol, the resulting product is a mixture of diol, monoester, and diester, so that an excessive extraction solvent and a multi-stage work process are required to separate only the monoester. And is inefficient.

  As a method for obtaining hydroxyalkyl (meth) acrylic acid ester in two steps, a method in which a vinyl ether-containing alcohol is transesterified and then devinylated in the presence of an acid catalyst and an alcohol has been reported (for example, see Patent Document 7). ). However, in this method, since a by-product such as ethylene glycol methyl acetal is formed during the devinylation reaction, it is necessary to remove this, but the alcohol used excessively during the reaction must be discarded by washing with water. It is not efficient.

German Patent No. 15118572 JP 10-298143 A Japanese Patent Laid-Open No. 11-43466 JP 2000-159727 A JP-A-8-53392 JP-A-2005-194201 Japanese Patent Laid-Open No. 10-182555

  This invention makes it a subject to provide the manufacturing method which can manufacture highly purified hydroxyalkyl (meth) acrylic acid ester efficiently, without requiring a complicated refinement | purification process.

As a result of various studies, the present inventors have found that a vinyl ether-containing alcohol is (meth) acrylated to give a vinyl ether-containing (meth) acrylic acid ester, and then dehydroxylated by coexisting water in the presence of an acid catalyst. It has been found that alkyl (meth) acrylic acid esters can be obtained efficiently. In addition, an acetal dimer compound (diester) is produced as a by-product during the devinylation reaction, but the acetal dimer is decomposed by adding water after the devinylation reaction to produce a high-purity hydroxyalkyl. It has been found that (meth) acrylic acid esters can be obtained.
That is, the present invention is as follows.

(1) A vinyl ether-containing alcohol is (meth) acrylated by a transesterification method to give a vinyl ether-containing (meth) acrylic acid ester. After performing a devinylation reaction in the presence of an acid catalyst and water, water is further added. The manufacturing method of the hydroxyalkyl (meth) acrylic acid ester characterized by including the process of performing a deacetalization reaction.

(2) The method for producing a hydroxyalkyl (meth) acrylic acid ester according to (1), wherein after the devinylation reaction is performed at a pressure in the reaction system of 20 to 40 kPa, the deacetalization reaction is performed at 10 kPa or less. .

(3) The method for producing a hydroxyalkyl (meth) acrylic acid ester according to (1) or (2), wherein the vinyl ether-containing alcohol is represented by the following general formula (I) or (II).

（一般式(Ｉ)中、ｎは３〜１１の整数を示す。）

(In general formula (I), n represents an integer of 3 to 11)

（一般式(ＩＩ)中、Ａはシクロペンチレン基又はシクロヘキシレン基を示す。）

(In general formula (II), A represents a cyclopentylene group or a cyclohexylene group.)

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method from which highly purified hydroxyalkyl (meth) acrylic ester can be obtained efficiently can be provided, without passing through complicated purification processes, such as distillation.

  An embodiment of a method for producing a hydroxyalkyl (meth) acrylic acid ester of the present invention will be described in detail.

  The method for producing a hydroxyalkyl (meth) acrylic acid ester of the present invention comprises (meth) acrylating a vinyl ether-containing alcohol by a transesterification method to give a vinyl ether-containing (meth) acrylic ester, and devinylating in the presence of an acid catalyst and water. It is characterized by including a step of performing a deacetalization reaction by adding water after the conversion reaction.

  In the present invention, first, the hydroxyl group of a vinyl ether-containing alcohol is esterified to obtain a vinyl ether-containing (meth) acrylic acid ester. The esterification method mainly includes dehydration esterification method using (meth) acrylic acid, transesterification method using lower (meth) acrylic acid ester, and acid halogen method using (meth) acrylic acid chloride. However, among them, the dehydration esterification method uses an acid catalyst, so that devinylation occurs at the same time and cannot be applied. Further, in the acid halogen method, halogen is eliminated by the reaction and remains in the system, and thus a purification treatment such as washing with water, adsorption or distillation is necessary. On the other hand, since the transesterification method has few impurities and does not require a purification operation, the transesterification method is adopted in the present invention.

  Examples of the vinyl ether-containing alcohol used in the present invention include the following general formula (I) such as 4-hydroxybutyl vinyl ether, 6-hydroxyhexyl vinyl ether, 9-hydroxynonyl vinyl ether, 10-hydroxydecanyl vinyl ether, and 12-hydroxydodecyl vinyl ether. ); Compounds represented by the following general formula (II) such as cyclohexanedimethanol monovinyl ether; and phenyldimethanol monovinyl ether.

（一般式(Ｉ)中、ｎは３〜１１の整数を示す。）

(In general formula (I), n represents an integer of 3 to 11)

（一般式(ＩＩ)中、Ａはシクロペンチレン基又はシクロヘキシレン基を示す。）

(In general formula (II), A represents a cyclopentylene group or a cyclohexylene group.)

  Specific examples of the lower (meth) acrylate used in the transesterification method include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, and butyl (meth) acrylate. . That is, the lower (meth) acrylic acid ester referred to in the present application means one having an alkyl group having 4 or less carbon atoms.

  In the transesterification reaction, it is preferable to use the lower (meth) acrylic acid ester in an equivalent amount to an excessive amount with respect to the vinyl ether-containing alcohol compound from the viewpoint of a short-time reaction, a high ester conversion rate, and post-treatment after the reaction. . Specifically, it is preferable to use the lower (meth) acrylic acid ester in the range of 1.0 to 20 mol with respect to 1 mol of the hydroxyl group that the vinyl ether-containing alcohol compound usually has. If the amount of the lower (meth) acrylic acid ester used is less than 1.0 mol relative to 1 mol of the hydroxyl group of the vinyl ether-containing alcohol compound, the reaction does not proceed sufficiently, and if it exceeds 20 mol, the concentration step after the reaction Takes a long time to deteriorate productivity.

  Catalysts used in the transesterification method include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; alkali metal carbonates such as lithium carbonate, sodium carbonate, and potassium carbonate; lithium methoxide, sodium Alkali metal alkoxides such as methoxide, sodium ethoxide and potassium t-butoxide; alkali metal amides such as lithium amide, sodium amide and potassium amide; tetramethyl orthotitanate, tetraethyl orthotitanate, tetrapropyl orthotitanate, orthotitanium Examples include titanium alkoxides such as tetraisopropyl acid and tetrabutyl orthotitanate; other aluminum alkoxides; tin alkoxides; Of these, side reactions are suppressed as much as possible, and the catalyst can be easily removed by adding water after completion of the reaction, and therefore, titanium alkoxide or aluminum alkoxide is preferable.

  Moreover, the usage-amount of a catalyst has the preferable range of 0.01-5.0 mass% normally with respect to the total amount of a lower (meth) acrylic acid ester and a vinyl ether containing alcohol compound. Even if the amount of catalyst exceeds 5.0% by mass, the reaction rate is hardly affected, and on the contrary, a large amount of water is required for removing the catalyst, which is uneconomical.

  In the transesterification reaction in the present invention, a known polymerization inhibitor can be added and used in combination. Examples of the polymerization inhibitor include phenols such as hydroquinone and hydroquinone monomethyl ether (also referred to as “methoquinone”); sulfur compounds such as phenothiazine and ethylenethiourea; copper salts such as copper dibutyldithiocarbamate; manganese salts such as manganese acetate; Nitro compounds, nitroso compounds, N-oxyl compounds such as 4-hydroxy-2,2,6,6-tetramethylpiperidinooxyl; and the like. The addition amount of the polymerization inhibitor is preferably 0.1% by mass or less with respect to the produced ester. If it exceeds 0.1% by mass, coloring due to the additive may occur.

  In the transesterification reaction, it is preferable to blow a small amount of molecular oxygen in order to prevent polymerization of the reaction solution during the reaction. As molecular oxygen, it is preferable to use it in a diluted state, and it is preferable to use air. The blowing of molecular oxygen is also preferable for preventing the polymerization of (meth) acrylic acid esters which are evaporated and exist as vapor or condensed on the upper wall of the tank.

Molecular oxygen means a ground-state triplet oxygen molecule (O ₂ ) formed by two oxygen atoms, and can directly participate in the reaction as it is, but it interacts with catalysts and reaction reagents. Means an oxygen molecule that can also participate in the reaction after being converted to a singlet oxygen molecule, oxygen atom, superoxide, peroxide, or the like.

  The amount of molecular oxygen introduced is influenced by the shape of the reactor and the stirring power, but is blown at a rate of 5 to 500 ml / min (25 to 2500 ml / min as air) with respect to 1 mol of the raw material vinyl ether-containing alcohol. That's fine. When the amount of molecular oxygen introduced is less than 5 ml / min, the effect of inhibiting polymerization is not sufficient, and when it exceeds 500 ml / min, the effect of extruding lower (meth) acrylic acid ester out of the system becomes stronger. Loss of the lower (meth) acrylic acid ester as

  The transesterification reaction in the present invention is preferably performed at 60 to 120 ° C. under normal pressure or reduced pressure. When the temperature is less than 60 ° C., the reaction rate is extremely slow, and when it exceeds 120 ° C., polymerization of the vinyl ether-containing (meth) acrylate obtained by the transesterification reaction is likely to occur, and coloration is likely to occur. .

  As a form of transesterification, it can carry out by the method generally known among those skilled in the art which manufactures (meth) acrylic acid ester. During the transesterification reaction, it is necessary to azeotropically distill off the by-produced lower alcohol with a lower (meth) acrylic acid ester and / or a solvent. For this reason, as a reaction apparatus, for example, a batch reaction tank attached to a rectification column is used.

  After completion of the transesterification reaction, the catalyst is deactivated with water, and excess low-boiling components are distilled off with a concentrator. Distillation of the low-boiling component by the concentrator is preferably performed under normal pressure or reduced pressure while maintaining the liquid temperature at 90 ° C. or less, and more preferably in the range of 50 to 70 ° C. When the liquid temperature exceeds 90 ° C., the vinyl ether-containing (meth) acrylic acid ester is likely to be colored or polymerized.

  The vinyl ether-containing (meth) acrylic acid ester from which the low-boiling components have been distilled off can remove insoluble components such as a deactivated catalyst remaining by filtration. In order to remove insolubles efficiently during filtration, it is preferable to use a filter aid such as diatomaceous earth.

  Subsequently, a method for obtaining a hydroxyalkyl (meth) acrylate ester by devinylation reaction of the vinyl ether-containing (meth) acrylate ester will be described.

  The devinylation reaction according to the present invention is carried out in the presence of an acid catalyst in the presence of water. The acetaldehyde produced during the devinylation reaction can be removed by reducing the pressure in the reaction system, but part of the acetaldehyde is taken into water and the hydroxyalkyl (meth) acrylic ester produced by the devinylation reaction. To form hydroxyalkyl (meth) acrylic acid ester methyl acetal (acetal dimer). When the acetal dimer remains, problems such as high viscosity and gelation due to a crosslinking reaction occur during polymerization. However, since the acetal dimerization reaction is a reversible reaction and is easily deacetalized in the presence of an acid catalyst, in the present invention, after the devinylation reaction, the deacetalization reaction described later is performed to perform the acetal dimerization reaction. Break down the production.

  As the acid catalyst that can be used in the devinylation reaction according to the present invention, usually, sulfuric acid, sodium hydrogen sulfate, paratoluenesulfonic acid, benzenesulfonic acid, methanesulfonic acid, solid acid (zeolite, amberlite, amberlist, Nafion etc.). Moreover, 0.1-10 mass% is preferable with respect to the vinyl ether containing (meth) acrylic acid ester made to react, and, as for the catalyst amount to be used, 0.5-3 mass% is more preferable. When the amount of the catalyst used is less than 0.1% by mass, the devinylation reactivity is remarkably lowered and the reaction becomes extremely slow. Moreover, when more than 10 mass%, there exists a tendency which produces | generates many by-products, such as an acetal dimer.

  The amount of water used in the devinylation reaction according to the present invention is not particularly limited as long as it is equimolar or more with respect to the vinyl ether-containing (meth) acrylic acid ester, but preferably vinyl ether-containing (meth) acrylic. By using 20 to 40% by mass with respect to the acid ester, the devinylation reaction proceeds rapidly, and the amount of acetal dimer produced can be suppressed. When the amount of water used is less than 20% by mass relative to the vinyl ether-containing (meth) acrylic acid ester, the amount of acetal dimer produced increases, and when it exceeds 40% by mass, the devinylation reaction is delayed. Furthermore, if the amount is less than equimolar, the progress of the devinylation reaction stops midway.

  The devinylation reaction according to the present invention is an exothermic reaction, and acetaldehyde generated by the reaction needs to be removed by reducing the pressure in the system. By controlling the reaction temperature to 60 ° C. or less, preferably 20 ° C. to 40 ° C., it is possible to obtain a high-purity hydroxyalkyl (meth) acrylic ester. Examples of the method for controlling the reaction temperature include cooling the reactor or gradually adding a vinyl ether-containing (meth) acrylic acid ester to the aqueous catalyst solution. In addition, after the end of heat generation, warm in a warm bath to maintain the temperature. If the reaction temperature is in the range of 20 ° C. to 40 ° C., the pressure in the system is about 20 to 40 kPa, and acetaldehyde can be efficiently removed.

  The present invention is characterized in that after the devinylation reaction is performed, water is further added to perform the deacetalization reaction. Although there is no restriction | limiting in particular as addition amount of water, Preferably it is 3-30 mass% on the basis of vinyl ether containing (meth) acrylic acid ester. When the amount of water used is outside this range, the deacetalization reaction does not proceed efficiently. Moreover, as a method for adding water, either a method of gradually dropping or a method of adding at a time is possible. Moreover, in order to remove acetaldehyde efficiently at the time of deacetalization, it is more preferable to make the system pressure 10 kPa or less.

  In the devinylation reaction and deacetal reaction of the present invention, in order to prevent polymerization of the reaction solution during the reaction, it is preferable to blow a small amount of molecular oxygen as in the case of the transesterification reaction.

  After completion of the deacetalization reaction, it is necessary to neutralize and remove the acid catalyst with a base. Examples of the base include hydroxides or salts of alkali metals and alkaline earth metals such as potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, potassium bicarbonate, and sodium bicarbonate. In addition, when separating and removing the aqueous layer after neutralization, for example, a solvent such as toluene or xylene can be used alone or in combination of two or more in order to increase the separation ability. A method of increasing the specific gravity can be used.

  After the neutralization, excess water or a solvent is distilled off when concentration is used. Concentration is preferably carried out under normal pressure or reduced pressure while keeping the liquid temperature at 90 ° C. or lower, more preferably in the range of 65 ° C. to 85 ° C. When the liquid temperature exceeds 90 ° C., there is a high possibility of causing coloring or polymerization of the hydroxyalkyl (meth) acrylic acid ester.

  After concentration, insolubles such as remaining neutralized salts can be removed by filtration. In order to remove insolubles efficiently during filtration, it is preferable to use a filter aid such as diatomaceous earth.

  The method for producing a hydroxyalkyl (meth) acrylic acid ester of the present invention obtains a high-purity hydroxyalkyl (meth) acrylic acid ester by carrying out a devinylation reaction and a deacetalization reaction by using water. Therefore, a production step other than filtration is not necessary, but a general purification method such as distillation can be carried out depending on the case.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

[Example 1]
(Synthesis of vinyloxybutyl methacrylate)
Put 4-hydroxybutyl vinyl ether (HBVE made by Maruzen Petrochemical Co., Ltd.) 1000g, methyl methacrylate 3000g, and methoquinone 0.65g into a 4L 4-neck round bottom separable flask, rectification tower (15 stages), stirrer, air introduction A tube and a thermometer were installed. Under stirring, heating was started while introducing dry air at 100 ml / min, and the pressure was adjusted to about 40 kPa so that the liquid temperature in the flask at reflux became 75 ° C., thereby removing moisture in the system. After confirming that the water content in the system was 300 ppm or less, 8.6 g of titanium tetraisopropoxide was added as a catalyst, and the pressure in the flask was controlled to about 60 kPa so that the reaction temperature was 95 ± 5 ° C. If the temperature at the top of the rectification column (column top temperature) was monitored during heating to reflux, the reflux ratio was adjusted so that the column top temperature would be about 60 ° C. because it approached the azeotropic temperature of methanol and methyl methacrylate produced. The reaction was carried out while distilling off methanol as an azeotrope with methyl methacrylate. Since the tower top temperature began to rise from about 4 hours after the reaction, the reaction was continued by gradually increasing the reflux ratio. When the reaction solution at the 5th hour of the reaction was analyzed by gas chromatography, the ester conversion rate was 99.2%. Therefore, the reaction was terminated. The reaction liquid was cooled, and when the liquid temperature reached 75 ° C., 250 g of 17% by mass saline was added to hydrolyze the catalyst. After standing for 15 minutes, the organic layer was taken into an eggplant-shaped flask by decantation, and after distilling off excess methyl methacrylate under reduced pressure using a rotary evaporator, the solution in the eggplant flask was filtered by suction filtration. As a result, 1522 g of vinyloxybutyl methacrylate was obtained.

(Synthesis of 4-hydroxybutyl methacrylate)
A 1 L 4-neck separable flask was charged with 2.5 g of paratoluenesulfonic acid and 150 g of pure water, and a stirrer, a thermometer, an air introduction tube, and a vacuum pump with a cooling trap were installed. While stirring, 500 g of vinyloxybutyl methacrylate synthesized above was slowly added to the flask while adjusting the liquid temperature to be kept at 40 ° C. After completion of the addition, the pressure was reduced to 30 kPa, stirring was continued for 1 hour while introducing dry air at 100 ml / min, and then the reaction solution was analyzed by gas chromatography. As a result, no vinyloxybutyl methacrylate peak was observed. However, since 19.8% of acetal dimer was produced by analysis by liquid chromatography, 25 g of pure water was added and the pressure was adjusted to 5 kPa to carry out the deacetalization reaction. When analyzed 1 hour after the reaction, the peak of the acetal dimer almost disappeared, so the reaction was terminated. The reaction completion solution was neutralized by adding 3.8 g of sodium hydrogen carbonate, and then mixed with 88 g of 17% brine and allowed to stand for 10 minutes until oil-water separation was completed. The organic layer was taken into an eggplant-shaped flask by decantation, and the water was distilled off under reduced pressure using a rotary evaporator. .

[Comparative Example 1]
A 1 L 4-neck separable flask was charged with 2.5 g of paratoluenesulfonic acid and 150 g of pure water, and a stirrer, a thermometer, an air introduction tube, and a vacuum pump with a cooling trap were installed. While stirring, 500 g of vinyloxybutyl methacrylate synthesized above was slowly added to the flask while adjusting the liquid temperature to be kept at 40 ° C. After completion of the addition, the pressure was reduced to 30 kPa, and stirring was continued for 1 hour while introducing dry air at 100 ml / min. After analyzing the reaction solution by gas chromatography, no peak of vinyloxybutyl methacrylate was observed. Ended. The reaction completion solution was neutralized by adding 3.8 g of sodium hydrogen carbonate, and then mixed with 88 g of 17% brine and allowed to stand for 10 minutes until oil-water separation was completed. The organic layer was taken into an eggplant-shaped flask by decantation, and water was distilled off under reduced pressure using a rotary evaporator. .

[Comparative Example 2]
A 1 L four-necked separable flask was charged with 2.5 g of paratoluenesulfonic acid and 175 g of pure water (that is, charged with the amount of water added after Example 1), a stirrer, a thermometer, and an air introduction tube A vacuum pump with a cooling trap was installed. While stirring, 500 g of vinyloxybutyl methacrylate synthesized above was slowly added to the flask while adjusting the liquid temperature to be kept at 40 ° C. After completion of the addition, the pressure was reduced to 30 kPa, and stirring was continued for 2 hours while introducing dry air at 100 ml / min. After analyzing the reaction solution by gas chromatography, no peak of vinyloxybutyl methacrylate was observed. Ended. The reaction completion solution was neutralized by adding 3.8 g of sodium hydrogen carbonate, and then mixed with 88 g of 17% brine and allowed to stand for 10 minutes until oil-water separation was completed. The organic layer was taken into an eggplant-shaped flask by decantation, and the water was distilled off under reduced pressure using a rotary evaporator. .

[Example 2]
(Synthesis of vinyloxybutyl acrylate)
Into a 4 L 4-neck round bottom separable flask, 1000 g of 4-hydroxybutyl vinyl ether (HBVE manufactured by Maruzen Petrochemical Co., Ltd.), 3000 g of ethyl acrylate, and 0.65 g of methoquinone were placed. A tube and a thermometer were installed. Under stirring, heating was started while introducing dry air at 100 ml / min, and the pressure was adjusted to about 40 kPa so that the liquid temperature in the flask at reflux became 75 ° C., thereby removing moisture in the system. After confirming that the water content in the system was 300 ppm or less, 8.6 g of titanium tetraisopropoxide was added as a catalyst, and the pressure in the flask was controlled to about 60 kPa so that the reaction temperature was 95 ± 5 ° C. When the temperature at the top of the rectification column (column top temperature) was monitored during heating to reflux, the reflux ratio was adjusted so that the column top temperature was about 70 ° C because it approached the azeotropic temperature of ethanol and ethyl acrylate. The reaction was carried out while distilling off methanol as an azeotrope with methyl methacrylate. Since the tower top temperature began to rise from about 4 hours after the reaction, the reaction was continued by gradually increasing the reflux ratio. When the reaction solution at the 5th hour of the reaction was analyzed by gas chromatography, the ester conversion rate was 99.0%. Therefore, the reaction was terminated. The reaction liquid was cooled, and when the liquid temperature reached 75 ° C., 250 g of 17% by mass saline was added to hydrolyze the catalyst. After standing for 15 minutes, the organic layer was taken into an eggplant-shaped flask by decantation, and after distilling off the excess ethyl acrylate under reduced pressure using a rotary evaporator, the solution in the eggplant flask was filtered by suction filtration. 1376 g of vinyloxybutyl acrylate was obtained.

(Synthesis of 4-hydroxybutyl acrylate)
A 1 L 4-neck separable flask was charged with 2.5 g of paratoluenesulfonic acid and 150 g of pure water, and a stirrer, a thermometer, an air introduction tube, and a vacuum pump with a cooling trap were installed. While stirring, 500 g of the vinyloxybutyl acrylate synthesized above was slowly added to the flask while adjusting the liquid temperature to be kept at 40 ° C. After completion of the addition, the pressure was reduced to 30 kPa, stirring was continued for 1 hour while introducing dry air at 100 ml / min, and then the reaction solution was analyzed by gas chromatography. As a result, no vinyloxybutyl acrylate peak was observed. However, in the analysis by liquid chromatography, 20.5% of acetal dimer was produced, so 25 g of pure water was added, and the pressure was adjusted to 5 kPa to carry out the deacetalization reaction. When analyzed 1 hour after the reaction, the peak of the acetal dimer disappeared, so the reaction was terminated. The reaction complete solution was neutralized by adding 3.8 g of sodium hydrogen carbonate, and then mixed with 86 g of 17% brine and allowed to stand for 10 minutes until oil-water separation was complete. The organic layer was taken into an eggplant-shaped flask by decantation, and the water was distilled off under reduced pressure using a rotary evaporator. Then, the liquid in the eggplant flask was filtered by suction filtration to obtain 385 g of the desired 4-hydroxybutyl acrylate Obtained at 91%.

[Comparative Example 3]
A 1 L 4-neck separable flask was charged with 2.5 g of paratoluenesulfonic acid and 150 g of pure water, and a stirrer, a thermometer, an air introduction tube, and a vacuum pump with a cooling trap were installed. While stirring, 500 g of the vinyloxybutyl acrylate synthesized above was slowly added to the flask while adjusting the liquid temperature to be kept at 40 ° C. After completion of the addition, the pressure was reduced to 30 kPa, and stirring was continued for 1 hour while introducing dry air at 100 ml / min. After analysis of the reaction solution by gas chromatography, no vinyloxybutyl acrylate peak was observed. Ended. The reaction complete solution was neutralized by adding 3.8 g of sodium hydrogen carbonate, and then mixed with 86 g of 17% brine and allowed to stand for 10 minutes until oil-water separation was complete. The organic layer was taken into an eggplant-shaped flask by decantation, and the water was distilled off under reduced pressure using a rotary evaporator. Then, the solution in the eggplant flask was filtered by suction filtration to obtain 372 g of the desired 4-hydroxybutyl acrylate Obtained at 88%.

[Example 3]
(Synthesis of cyclohexanedimethanol vinyl ether acrylate)
Into a 1 L 4-neck round bottom flask, 300 g of cyclohexanedimethanol monovinyl ether (CHMVE manufactured by Maruzen Petrochemical Co., Ltd.), 600 g of ethyl acrylate, and 0.20 g of methoquinone were placed. A rectification tower (15 stages), a stirrer, an air introduction tube, A thermometer was installed. Under stirring, heating was started while introducing dry air at 100 ml / min, and the pressure was adjusted to about 40 kPa so that the liquid temperature in the flask at reflux became 75 ° C., thereby removing moisture in the system. After confirming that the water content in the system was 300 ppm or less, 2.6 g of titanium tetraisopropoxide was added as a catalyst, and the pressure in the flask was controlled to about 60 kPa so that the reaction temperature was 95 ± 5 ° C. When the temperature at the top of the rectification column (column top temperature) was monitored during heating to reflux, the reflux ratio was adjusted so that the column top temperature was about 70 ° C because it approached the azeotropic temperature of ethanol and ethyl acrylate. The reaction was carried out while distilling off ethanol as an azeotrope with ethyl acrylate. Since the tower top temperature began to rise from about 2 hours after the reaction, the reaction was continued by gradually increasing the reflux ratio. When the reaction solution at 3 hours after the reaction was analyzed by gas chromatography, the ester conversion rate was 99.4%, so the reaction was terminated. The reaction liquid was cooled, and when the liquid temperature reached 75 ° C., 100 g of 17% by mass saline was added to hydrolyze the catalyst. After standing for 15 minutes, the organic layer was taken into a eggplant-shaped flask by decantation, and using a rotary evaporator, excess ethyl acrylate was distilled off under reduced pressure, and then the liquid in the eggplant flask was filtered by suction filtration. 385 g of the desired cyclohexanedimethanol vinyl ether acrylate was obtained.

(Synthesis of cyclohexanedimethanol monoacrylate)
A 500 mL four-necked separable flask was charged with 1.0 g of paratoluenesulfonic acid and 60 g of pure water, and a stirrer, thermometer, air introduction tube, and vacuum pump with a cooling trap were installed. While stirring, 200 g of cyclohexanedimethanol vinyl ether acrylate synthesized in Production Example 3 was slowly added to the flask while adjusting the liquid temperature to be kept at 40 ° C. After completion of the addition, the pressure was reduced to 30 kPa, stirring was continued for 1 hour while introducing dry air at 100 ml / min, and then the reaction solution was analyzed by gas chromatography. As a result, no vinyloxybutyl acrylate peak was observed. However, since the analysis by liquid chromatography produced 13.6% of acetal dimer, 10 g of pure water was added and the pressure was adjusted to 5 kPa to carry out the deacetalization reaction. When analyzed 1 hour after the reaction, the peak of the acetal dimer disappeared, so the reaction was terminated. After completion of the reaction, the reaction mixture was neutralized with 1.5 g of sodium hydrogen carbonate, and then mixed with 35 g of 17% brine and allowed to stand for 10 minutes until the oil and water were completely separated. The organic layer was taken into an eggplant flask by decantation, and water was distilled off under reduced pressure using a rotary evaporator. Got in.

[Comparative Example 4]
A 500 mL four-necked separable flask was charged with 1.0 g of paratoluenesulfonic acid and 60 g of pure water, and a stirrer, thermometer, air introduction tube, and vacuum pump with a cooling trap were installed. While stirring, 200 g of cyclohexanedimethanol vinyl ether acrylate synthesized in Production Example 3 was slowly added to the flask while adjusting the liquid temperature to be kept at 40 ° C. After completion of the addition, the pressure was reduced to 30 kPa, and stirring was continued for 1 hour while introducing dry air at 100 ml / min. After analysis of the reaction solution by gas chromatography, no vinyloxybutyl acrylate peak was observed. Ended. After completion of the reaction, the reaction mixture was neutralized with 1.5 g of sodium hydrogen carbonate, and then mixed with 35 g of 17% brine and allowed to stand for 10 minutes until the oil and water were completely separated. The organic layer was taken into an eggplant flask by decantation, and the water was distilled off under reduced pressure using a rotary evaporator. Got in.

4HBMA: 4-ヒト゛ロキシエチルメタクリレート
4HBA: 4-ヒト゛ロキシエチルアクリレート
CHDM-MA: シクロヘキサンシ゛メタノールモノアクリレート

4HBMA: 4-Hydroxyethyl methacrylate
4HBA: 4-Hydroxyethyl acrylate
CHDM-MA: Cyclohexanedimethanol monoacrylate

  From Table 1 above, in Examples 1 to 3 in which water was further added after the devinylation reaction for deacetalization, the acetal dimer was greatly reduced, and in Comparative Example 2, the examples were The amount of water used at the initial stage of 1 and the amount of water at the time of post-addition were combined and used initially, but it can be seen that an acetal dimer is present.

Claims (3)

  A vinyl ether-containing alcohol is (meth) acrylated by transesterification to give a vinyl ether-containing (meth) acrylic acid ester. After devinylation reaction in the presence of an acid catalyst and water, water is further added to deacetalize. The manufacturing method of the hydroxyalkyl (meth) acrylic acid ester characterized by including the process of performing reaction.   The method for producing a hydroxyalkyl (meth) acrylic acid ester according to claim 1, wherein after the devinylation reaction is performed at a pressure in the reaction system of 20 to 40 kPa, the deacetalization reaction is performed at 10 kPa or less. The manufacturing method of the hydroxyalkyl (meth) acrylic acid ester of Claim 1 or 2 with which vinyl ether containing alcohol is represented by the following general formula (I) or (II).

(In general formula (I), n represents an integer of 3 to 11)

(In general formula (II), A represents a cyclopentylene group or a cyclohexylene group.)