Method for producing esters of (meth)acrylic acid from amino alcohols by enzymatic transesterification

Abstract

The present invention relates to the synthesis of esters of methacrylic or acrylic acid (hereinafter referred to as (meth)acrylates) from dialkylamino alcohols by transesterification catalyzed by at least one supported enzyme.

Description

[Technical Field]

[0001] The present invention relates to the synthesis of esters of methacrylic or acrylic acid, designated herein as meth(acrylates), from dialkylamino alcohols by transesterification catalyzed by at least one supported enzyme. [Background technology]

[0002] For example, from document EP 960877 it is known to prepare esters of (meth)acrylic acid by a transesterification process by reaction of an alcohol with an alkyl (meth)acrylate: a light alcohol is produced during the synthesis and is removed in the form of an azeotrope with the light alkyl (meth)acrylate.

[0003] The industrial production of dialkylaminoalkyl (meth)acrylates is generally catalyzed by organometallic complexes.

[0004] The choice of catalyst depends on various criteria, in particular on the nature of the alkyl (meth)acrylate used, but also on the nature of the alcohol used to prepare the ester of (meth)acrylic acid. In addition to the efficiency and selectivity criteria, other factors may come into play, such as commercial availability, price, or catalyst toxicity.

[0005] Titanium alkoxides have proven to be active and selective catalysts, and their use is particularly recommended in processes for the synthesis of dialkylaminoalkyl(meth)acrylates. Document EP 298867 describes, inter alia, the preparation of N,N-dimethylaminoethyl acrylate (DMAEA) in the presence of tetraethyl titanate by a transesterification process by reaction of ethyl acrylate with dimethylaminoethanol.

[0006] In document EP 960877, dialkylaminoalkyl(meth)acrylates are obtained from aminoalcohols and methyl or ethyl(meth)acrylate in the presence of a transesterification catalyst selected from tetrabutyl titanate, tetraethyl titanate, and tetra(2-ethylhexyl) titanate. However, to obtain a high-purity product, it is first necessary to carry out a tailing operation, i.e., removal of the catalyst and heavy products, followed by a topping operation and a final rectification of the crude reaction mixture.

[0007] When producing dialkylaminoalkyl (meth)acrylates such as DMAEA by transesterification from methyl (meth)acrylate, it is difficult to imagine the use of titanium alkoxides such as tetraethyl titanate due to the progressive formation of a white precipitate, which is completely insoluble in the reaction medium and becomes tetramethyl titanate. Specifically, during the transesterification, in the presence of the generated methanol, the titanic acid used undergoes ligand exchange and the formation of methyl titanate, which is insoluble and is the end point. The catalyst deactivation phenomenon, and the resulting slowdown in the reaction rate as well as clogging of the reaction vessel and its attachments, are unacceptable on an industrial scale.

[0008] Document EP 2099739 describes a group of catalysts based on titanium and polyols, which make it possible to catalyze the synthesis of (meth)acrylic esters, in particular from methyl (meth)acrylate by transesterification, without observing the phenomenon of catalyst deactivation and clogging of the reaction vessel. In addition to being highly active and selective, these catalysts have the advantage of not precipitating solids during the reaction, unlike the aforementioned alkyl titanates, which produce insoluble methyl titanate in the presence of methanol.

[0009] The organometallic catalysts currently used in the industrial production of aminoalkyl (meth)acrylates produce significant amounts of Michael adducts and polymers during the reaction and purification. Additionally, the use of these organometallic catalysts generates waste products that are difficult to dispose of and have not been upgraded to a high degree.

[0010] In document JPH04 79889, alkylaminoalkyl esters of acrylic or methacrylic acid were obtained by transesterification of light (meth)acrylic acid esters and alkylaminoalkyl alcohols in the presence of enzymes or microorganisms capable of asymmetrically hydrolyzing esters. The enzymes were derived from microorganisms belonging to the Rhizopus, Mucor, Aspergillus, Candida, Pseudomonas Alcaligenes, Achromobacter, or Bacillus genera. In Example 1, dimethylaminoethyl acrylate was produced by the enzymatic reaction between methyl acrylate and dimethylaminoethanol. In Example 2, dimethylaminoethyl methacrylate was enzymatically obtained from ethyl methacrylate and dimethylaminoethanol. In both cases, the yields were up to 3.1%, as calculated from the data in Table 2. These yields are incompatible with industrial application of the process. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] EP960877 [Patent Document 2] EP298867 [Patent Document 3] EP2099739 [Patent Document 4] JPH04 79889 Summary of the Invention [Problem to be solved by the invention]

[0012] The present invention proposes an improved method for producing aminoalkyl (meth)acrylates, which includes a catalyst that is biobased and can be sustainably produced.

[0013] It has now been found that the synthesis of dialkylaminoalkyl(meth)acrylates can be carried out in the presence of at least one enzyme suitable for transesterification. The enzymatic reaction is found to be highly selective, leading to high product purity. The enzymatic reaction can also be carried out on an industrial scale. [Means for solving the problem]

[0014] The present invention relates to an optimized process for the synthesis of (meth)acrylates of dialkylamino alcohols by transesterification of dialkylamino alcohols with alkyl (meth)acrylates using supported enzymes, more particularly lipases, as catalysts.

[0015] This heterogeneous catalyst allows for the production of products at lower temperatures than those typically used with organometallic catalysts, leading to better selectivity. This improved selectivity results in approximately 100-fold less Michael adduct in batch mode, and polymerization of the resulting (meth)acrylic esters does not occur, thus obtaining the (meth)acrylates (the marketable products), resulting in savings on polymerization inhibitors, which are often used on a large scale during the synthesis of dialkylaminoalkyl (meth)acrylates. Because inhibitors are derived from petrochemicals, limiting their use reduces the environmental impact of the production process. Michael adducts are typically subjected to cracking to regenerate upgradeable molecules. This cracking process is energy-intensive, requiring high temperatures (above 150 °C). Finally, the use of a partially biobased catalyst allows for a reduction in the environmental footprint of the production process.

[0016] The optimized process shows reaction conditions with very high yields and excellent selectivity, and the ability to reuse the catalytic charge over several successive batches. In addition, supported enzymes have the advantage of being usable in continuous processes. DETAILED DESCRIPTION OF THE INVENTION

[0017] The present invention relates to a method for synthesizing dialkylaminoalkyl acrylates and dialkylaminoalkyl methacrylates (hereinafter referred to as dialkylaminoalkyl (meth)acrylates) by transesterification, including light (meth)acrylates of formula (1), where R1 = H or methyl, and R2 is a saturated or unsaturated, linear or branched alkyl chain containing 1 to 4 carbon atoms, and dialkylaminoalcohols of formula (2), where R3 and R4 are saturated, linear or branched alkyl chains or aromatic groups, and n is 1 to 6. Regarding the method. [ka] [ka]

[0018] Characteristically, the process according to the invention is carried out in the presence of a transesterification catalyst consisting of at least one supported enzyme.

[0019] According to many implementations, the method includes, where appropriate, a combination of the following aspects:

[0020] The ratio (1) / (2) between the light (meth)acrylate and the dialkylamino alcohol varies in the range of 1-20, more particularly 1-10.

[0021] The at least one enzyme is used in immobilized form. The enzyme may be chemically or physically immobilized.

[0022] The supported enzyme may be carried out in the form of a fixed bed comprising various layers of different lipases, or in a retaining basket, or by any other means that allows the supported enzyme to be maintained in contact with the reactants in the reaction vessel.

[0023] Preferably, the supported catalyst used can be immobilized in various ways known to those skilled in the art: for example, it is possible to imagine a fixed bed consisting of various layers of different lipases.

[0024] According to one embodiment, said at least one enzyme belongs to the large family of carboxylic ester hydrolases EC 3.1.1.

[0025] According to one embodiment, the process is carried out in the presence of an enzyme cocktail, "enzyme cocktail" being understood to mean a mixture of different lipases or esterases making it possible to increase the substrate specificity.

[0026] For example, the use of a mixture of several enzymes in catalytic amounts can be envisaged, for example a mixture of at least two of the following enzymes: Lipozyme® TL IM, Lipozyme® CALB L, Lipozyme® TL 100 L, Novocor® AD L, Novozym® 435, Lipozyme® RM, Novozym® 51032, Palatase® 20000 L, Resinase® HT.

[0027] The examples of enzyme mixtures listed above are not limiting.

[0028] According to one embodiment, the method is carried out in the presence of two enzymes.

[0029] According to one embodiment, the method is carried out in the presence of three enzymes.

[0030] According to one embodiment, the method is carried out in the presence of one enzyme.

[0031] According to one embodiment, the enzyme is a triacylglycerol lipase (EC 3.1.1.3).

[0032] According to one embodiment, the enzyme is a lipase extracted from Candida antartica.

[0033] According to one embodiment, the enzyme is Candida antartica lipase B (CALB), which is commercially available, for example in the form of Novozym® 435.

[0034] According to one embodiment, the method according to the invention uses Candida antartica lipase B immobilized on a macroporous resin of the poly(methyl methacrylate) type cross-linked with divinylbenzene.

[0035] The amount of supported enzyme added to the reaction medium may vary in the range of 0.1% to 10% by weight, and preferably 0.25% to 5% by weight, and even more preferably 0.5% to 3% by weight, relative to the total weight of the light (meth)acrylate and the dialkylamino alcohol.

[0036] According to one embodiment, the synthesis of the dialkylaminoalkyl(meth)acrylate is carried out without a solvent.

[0037] According to one embodiment, no polymerization inhibitors are added to the reaction medium.

[0038] According to one embodiment, the reaction mixture is stabilized by the addition of a polymerization inhibitor, which may be phenothiazine (PTZ), hydroquinone (HQ), hydroquinone monomethyl ether (HQME), di-tert-butyl-p-cresol (BHT), para-phenylenediamine, TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy), di-tert-butylcatechol, TEMPO derivatives such as OH-TEMPO, manganese acetate, or any mixture thereof in any ratio, in an amount of 50 ppm to 500 ppm, preferably 150 ppm to 1000 ppm, in the reaction medium.

[0039] The reaction temperature may vary within the range of 10°C to 100°C, preferably 40°C to 70°C.

[0040] The synthesis method according to the present invention may be carried out batchwise or continuously, with or without azeotropic distillation. In batchwise experiments, the final total amount of Michael adduct in the reaction medium does not exceed 0.01 mole per mole of dialkylaminoalkyl(meth)acrylate produced.

[0041] The reaction may be carried out at atmospheric pressure or under reduced pressure.

[0042] The duration of the reaction varies depending on the type of reaction (in a closed medium or in a batch mode, with or without distillation of the light alcohol / light (meth)acrylate azeotrope).

[0043] The supported enzyme is maintained in the reaction vessel in the form of a fixed bed or by any type of filter method and carried out. The maintenance of enzyme activity depends on the molar ratio between the light (meth)acrylate and the dialkylaminoalkyl. A relative yield of 30% to 60% for 10 consecutive cycles is observed in the batch process with distillation of the light alcohol / light (meth)acrylate azeotrope. In the continuous process without distillation of the light alcohol / light (meth)acrylate azeotrope, the yield may be maintained for 25 days with a maximum loss of 10%.

[0044] The process according to the invention is used in particular for the preparation of dimethylaminoethyl acrylate (DMAEA), dimethylaminopropyl acrylate, diethylaminoethyl acrylate, tert-butylaminoethyl acrylate, dimethylaminoethyl methacrylate (DMAEMA).

[0045] According to one embodiment, the light alkyl (meth)acrylate is ethyl acrylate. Ethanol is produced during the synthesis and is removed in the form of an azeotrope with ethyl (meth)acrylate.

[0046] According to one embodiment, the light alkyl (meth)acrylate is methyl methacrylate. Methanol is produced during the synthesis and is removed in the form of an azeotrope with methyl (meth)acrylate.

[0047] The following examples illustrate the invention without, however, limiting its scope. Percentages are expressed as percentages by weight. [Example]

[0048] General Procedure for Examples 1-6 The supported enzyme was introduced into the reaction vessel, followed by the light (meth)acrylate, the dialkylamino alcohol and the polymerization inhibitor. The reaction vessel was hermetically closed and the reaction medium was stirred at 50°C for 24 hours. After returning to ambient temperature, the medium was filtered and analyzed by gas chromatography.

[0049] Example 1: Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 The reaction parameters and the results obtained are shown in Table 1. [ka]

[0050] [Table 1]

[0051] Example 2: Synthesis of N,N-diethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-diethylaminoethanol catalyzed by Novozym® 435 [ka] The reaction parameters and the results obtained are shown in Table 2.

[0052] [Table 2]

[0053] Example 3: Synthesis of N,N-dimethylaminopropyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminopropan-1-ol catalyzed by Novozym® 435 [ka] The reaction parameters and the results obtained are shown in Table 3.

[0054] [Table 3]

[0055] Example 4: Synthesis of 1-methyl-2-N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminopropan-2-ol catalyzed by Novozym® 435 [ka] The reaction parameters and the results obtained are shown in Table 4.

[0056] [Table 4]

[0057] Example 5: Synthesis of N,N-dimethylaminoethyl acrylate from methyl acrylate (MA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 [ka] The reaction parameters and the results obtained are shown in Table 5.

[0058] [Table 5]

[0059] Example 6: Synthesis of N,N-dimethylaminoethyl methacrylate from methyl methacrylate (MMA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 [ka] The reaction parameters and the results obtained are shown in Table 6.

[0060] [Table 6]

[0061] These results show that: - The yield was better for the acrylate series than for the methacrylate series (Example 6 vs. Examples 1-5). - Disturbance in the tertiary amine function does not affect the yield of the reaction (Example 2 vs. Example 1). The reaction is less successful with branched dialkylamino alcohols than with linear ones (Example 4 vs. Examples 1-3).

[0062] General Procedure for Examples 7-11 The enzyme catalyst was introduced into a stirred reaction vessel, followed by the light (meth)acrylate and dialkylamino alcohol. Phenothiazine was added to stabilize the reaction. The reaction vessel was topped with a distillation column, which allowed the distillation of the light alcohol / light (meth)acrylate azeotrope. The reaction medium was stirred at 50°C for 3 hours under a pressure of 13,000 Pa. After returning to ambient pressure and temperature, the reaction medium was filtered and analyzed by gas chromatography.

[0063] Example 7: Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 1.0% by weight of Novozym® 435 was used, relative to the weight of the EA / DMAE mixture. Ethyl acrylate and N,N-dimethylaminoethanol were introduced at an EA / DMAE molar ratio of 3. 2000 ppm of phenothiazine was added to stabilize the reaction. The yield obtained was 70%, with 4×10 per mole of N,N-dimethylaminoethyl acrylate produced. -3 The total formation of Michael adducts was 1.2 moles.

[0064] Example 8: Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 2.0% by weight of Novozym® 435 was used, relative to the weight of the EA / DMAE mixture. Ethyl acrylate and N,N-dimethylaminoethanol were introduced at an EA / DMAE molar ratio of 3. 2000 ppm of phenothiazine was added to stabilize the reaction. The yield obtained was 96%, with 2.5 x 10 per mole of N,N-dimethylaminoethyl acrylate produced. -3 The total formation of Michael adducts was 1.2 moles.

[0065] Example 9: Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 1.0% by weight of Novozym® 435 was used, relative to the weight of the EA / DMAE mixture. Ethyl acrylate and N,N-dimethylaminoethanol were introduced at an EA / DMAE molar ratio of 5. 2000 ppm of phenothiazine was added to stabilize the reaction. The yield obtained was 99%, with 1.1 x 10 per mole of N,N-dimethylaminoethyl acrylate produced. -3 The total formation of Michael adducts was 1.2 moles.

[0066] Example 10: Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 1.5% by weight of Novozym® 435 was used, based on the weight of the EA / DMAE mixture. Ethyl acrylate and N,N-dimethylaminoethanol were introduced at an EA / DMAE molar ratio of 3. 200 ppm of phenothiazine was added to stabilize the reaction. The yield obtained was 98%, and no polymer was detected by size exclusion chromatography.

[0067] Example 11: Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym® 435 1.5% by weight of Novozym® 435 was used, based on the weight of the EA / DMAE mixture. Ethyl acrylate and N,N-dimethylaminoethanol were introduced at an EA / DMAE molar ratio of 3. No inhibitor was added to stabilize the reaction. The yield obtained was 95%, and no polymer was detected by size exclusion chromatography.

[0068] Example 12: Comparative Example for Examples 7 to 9. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate and N,N-dimethylaminoethanol catalyzed by ethyl titanate Ethyl acrylate (EA) was introduced into a stirred reaction vessel, followed by N,N-dimethylaminoethanol (DMAE) in an EA / DMAE molar ratio of 1.6, followed by ethyl titanate (1% by mass). 2000 ppm of phenothiazine was added to stabilize the reaction. The reaction vessel was topped with a distillation column that allowed the distillation of the EA / ethanol azeotrope. The reaction medium was stirred at 110 °C under a pressure of 42000 Pa for 3 hours. After returning to ambient pressure and temperature, the reaction medium was filtered and analyzed by gas chromatography. The yield of N,N-dimethylaminoethyl acrylate obtained was 80%, with 2.9 × 10 of N,N-dimethylaminoethyl acrylate per mole of N,N-dimethylaminoethyl acrylate produced. -1 was the total amount of Michael adduct in moles.

[0069] Example 13: Comparative Example to Example 10. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate and N,N-dimethylaminoethanol catalyzed by ethyl titanate Ethyl acrylate (EA) was introduced into a stirred reaction vessel, followed by N,N-dimethylaminoethanol (DMAE) in an EA / DMAE molar ratio of 1.6, followed by ethyl titanate (1% by weight). 200 ppm of phenothiazine was added to stabilize the reaction. The reaction vessel was topped with a distillation column that allowed the distillation of the EA / ethanol azeotrope. The reaction medium was stirred at 110 °C under a pressure of 42,000 Pa for 3 hours. After returning to ambient pressure and temperature, the reaction medium was filtered and analyzed by gas chromatography. The yield of N,N-dimethylaminoethyl acrylate was 73%, and the presence of the polymer was detected by size exclusion chromatography.

[0070] Example 14:Comparative Example to Example 11. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate and N,N-dimethylaminoethanol catalyzed by ethyl titanate Ethyl acrylate (EA) was introduced into a stirred reaction vessel, followed by N,N-dimethylaminoethanol (DMAE) in an EA / DMAE molar ratio of 1.6, followed by ethyl titanate (1% by weight). To stabilize the reaction, no polymerization inhibitor was added. The reaction vessel was topped with a distillation column, which allowed the distillation of the EA / ethanol azeotrope. The reaction medium was stirred at 110 °C under a pressure of 42,000 Pa for 3 hours. After returning to ambient pressure and temperature, the reaction medium was filtered and analyzed by gas chromatography. The yield of N,N-dimethylaminoethyl acrylate obtained was 79%, and the presence of the polymer was detected by size exclusion chromatography.

[0071] Examples 7, 8, and 9 show yields of 70% to 99%, with 1×10 per mole of product produced. -3 ~4×10 -3 The molar Michael adduct content is about 100 times lower than that in Example 12, which involves the organometallic catalyst ethyl titanate. The increased selectivity is an advantageous factor in industrial production.

[0072] On the other hand, Examples 10 and 11 did not detect the presence of polymers, in contrast to Examples 13 and 14, which contained ethyl titanate as catalyst with a low or no phenothiazine content in the reaction medium during weak stabilization, or even without polymerization inhibitors. The process according to the invention, involving at least one supported enzyme in a batch mode with distillation of the light alcohol / light (meth)acrylate azeotrope, therefore provided better selectivity of reaction for Michael adduct and polymerization than the organometallic catalyst ethyl titanate.

[0073] General procedure for Examples 15-17: Recycling of catalytic amount (supported enzyme) over several consecutive batches Ethyl acrylate was introduced into a stirred reaction vessel, followed by N,N-dimethylaminoethyl and the enzyme catalyst. 2000 ppm of phenothiazine was added to stabilize the reaction. The reaction vessel was topped with a distillation column, which allowed the distillation of the light alcohol / light acrylate azeotrope. The reaction medium was stirred at 50 °C under a pressure of 13000 Pa for 3 hours. After returning to ambient pressure and temperature, the reaction medium was filtered and analyzed by gas chromatography. The (supported enzyme) catalytic amount was retained in the reaction vessel and used with fresh reactants for the continuous synthesis.

[0074] Example 15: Continuous synthesis of N,N-dimethylaminoethyl acrylate catalyzed by Novozym® 435 Ethyl acrylate (EA) and N,N-dimethylaminoethylethanol (DMAE) were introduced in an EA / DMAE molar ratio of 3, and 1.5% by weight of Novozym® 435 was used as catalyst. The productivity of N,N-dimethylaminoethyl acrylate over 9 successive cycles was 108 g per gram of Novozym® 435. The yields obtained are shown in Table 7.

[0075] [Table 7]

[0076] Example 16: Continuous synthesis of N,N-dimethylaminoethyl acrylate catalyzed by Novozym® 435 Ethyl acrylate (EA) and N,N-dimethylaminoethylethanol (DMAE) were introduced in an EA / DMAE molar ratio of 5, and 1.5% by weight of Novozym® 435 was used as catalyst. The productivity of N,N-dimethylaminoethyl acrylate over 10 successive cycles was 117 g per gram of Novozym® 435. The yields obtained are shown in Table 8.

[0077] [Table 8]

[0078] Example 17: Continuous synthesis of N,N-dimethylaminoethyl acrylate catalyzed by Lipase CL Amino IM Ethyl acrylate (EA) and N,N-dimethylaminoethyl ethanol (DMAE) were introduced at an EA / DMAE molar ratio of 5, and 1.5 wt% Lipase CL Amino IM was used as the catalyst. The productivity of N,N-dimethylaminoethyl acrylate over 10 consecutive cycles was 114 g per gram of Lipase CL Amino IM. The yields obtained are shown in Table 9.

[0079] [Table 9]

[0080] The maintenance of enzyme activity depends on the molar ratio between the light (meth)acrylate and the dialkylaminoalkyl. Over 10 consecutive cycles, relative yields of 30% to 60% were observed.

[0081] Example 18: Continuous synthesis of N,N-dimethylaminoethyl acrylate (DMAEA) catalyzed by Novozym® 435 7.8 g of Novozym® 435 enzyme support was introduced into a jacketed piston reactor containing circulating silicone oil, and immobilized on the piston using cotton at the end point. A mixture of ethyl acrylate and N,N-dimethylaminoethanol containing 200 ppm of phenothiazine was continuously fed into the piston reactor at a molar ratio of 5. The feed rate was an average of 14 g / h, and the oil circulation in the piston reactor jacket was heated to 50°C. The reaction yield was 68% at the start and maintained at greater than 60% for 27 days. The amount of adduct produced during this continuous reaction was 7 x 10 per mole of DMAEA produced. -4 ~15×10 -4 The results are shown in Table 10.

[0082] Table 10

Claims

1. 1. A method for synthesizing dialkylaminoalkyl(meth)acrylates by transesterification, comprising: In the presence of a transesterification enzyme, characterized by comprising at least one supported enzyme, Known as light (meth)acrylates of formula (1), R １ = H or methyl, and R ２ is a saturated or unsaturated, linear or branched alkyl chain containing 1 to 4 carbon atoms, and Dialkylamino alcohols of formula (2), R ３ , R ４ is a saturated, linear or branched alkyl chain or an aromatic group, and n is 1 to 6; 【Chemistry 1】 【Chemistry 2】 A method comprising:

2. 2. The method according to claim 1, wherein the ratio between the light (meth)acrylate and the dialkylamino alcohol varies in the range of 1 to 20, more particularly 1 to 10.

3. 3. The method according to claim 1 or 2, wherein at least one of the enzymes belongs to the family of carboxylic ester hydrolases EC 3.1.

1.

4. 4. The process according to claim 1, which is carried out in the presence of an enzyme mixture formed from a mixture of different lipases or esterases.

5. The method according to any one of claims 1 to 3, wherein the enzyme is triacylglycerol lipase (EC 3.1.1.3).

6. 6. The method of claim 5, wherein the enzyme is lipase B from Candida antartica.

7. 7. The method according to any one of claims 1 to 6, wherein the amount of supported enzyme added to the reaction medium varies in the range of 0.1% to 10% by weight, preferably 0.25% to 5% by weight, and even more preferably 0.5% to 3% by weight, relative to the sum of the weights of the light acrylate and the dialkylamino alcohol.

8. The process according to any one of claims 1 to 7, wherein the transesterification reaction is carried out without a solvent.

9. 9. The process according to any one of claims 1 to 8, wherein the reaction mixture is stabilized by adding to the reaction medium a polymerization inhibitor selected from the group consisting of phenothiazine, hydroquinone, hydroquinone monomethyl ether, di-tert-butyl-par-cresol, para-phenylenediamine, TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy), di-tert-butylcatechol, TEMPO derivatives, manganese acetate, alone or in any mixture in any ratio, in a content between 50 ppm and 5000 ppm, preferably between 150 ppm and 1000 ppm.

10. The method according to any one of claims 1 to 8, wherein the transesterification reaction is carried out without a polymerization inhibitor.

11. 11. The process according to any one of claims 1 to 10, wherein the transesterification reaction is carried out batchwise with or without distillation of the light alcohol / light (meth)acrylate azeotrope.

12. 11. The process according to any one of claims 1 to 10, wherein the transesterification reaction is carried out continuously with or without distillation of the light alcohol / light (meth)acrylate azeotrope.

13. The method according to any one of claims 1 to 12, wherein the supported enzyme is carried out in the form of a fixed bed.

14. 14. The process according to any one of claims 1 to 13 for the preparation of dimethylaminoethyl acrylate (DMAEA), dimethylaminopropyl acrylate, diethylaminoethyl acrylate, tert-butylaminoethyl acrylate, dimethylaminoethyl methacrylate (DMAEMA).

15. 12. The method of claim 11, wherein the final total amount of Michael adduct in the reaction medium does not exceed 0.01 moles per mole of dialkylaminoalkyl(meth)acrylate produced.

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