Process for the production of (METH)acrylic esters from amino alcohols by enzymatic transesterification

Abstract

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

Description

[0001] TITLE: PROCESS FOR THE PRODUCTION OF ACRYLIC (METH) ESTERS FROM AMINO ALCOHOLS BY ENZYMATIC TRANSESTERIFICATION

[0002] Technical field

[0003] The present invention relates to the synthesis of esters of methacrylic acid or acrylic acid, hereinafter referred to as (meth)acrylates, from dialkylaminoalcohols by transesterification catalyzed by at least one supported enzyme.

[0004] Prior art and technical problem

[0005] It is known, for example from EP 960877, to prepare (meth)acrylic esters by a transesterification process by reacting an alkyl (meth)acrylate with an alcohol. During the synthesis, light alcohol is generated, which is eliminated in the form of an azeotrope with the light alkyl (meth)acrylate.

[0006] The industrial manufacture of dialkylaminoalkyl (meth)acrylates is generally catalyzed by organometallic complexes.

[0007] The choice of catalyst depends on various criteria, including the nature of the alkyl (meth)acrylate used, but also the nature of the alcohol used to prepare the (meth)acrylic ester. In addition to the criteria of efficiency and selectivity, other factors may be involved, such as commercial availability, price or toxicity of the catalyst.

[0008] Titanium alcoholates have proven to be active and selective catalysts and their use is recommended in particular in processes for the synthesis of dialkylaminoalkyl (meth)acrylates. Document EP 298867 describes in particular the preparation of N,N-dimethylaminoethyl acrylate (ADAME) in the presence of tetraethyl titanate according to a transesterification process by reaction of ethyl acrylate with dimethylaminoethanol.

[0009] In EP 960877, dialkylaminoalkyl (meth)acrylates are obtained in the presence of a transesterification catalyst selected from tetrabutyl, tetraethyl and tetra(2-ethylhexyl) titanates from methyl or ethyl (meth)acrylate with an amino alcohol. To obtain a high-purity product, however, it is necessary to first carry out tailing, i.e. removal of the catalyst and heavy products, followed by topping and final rectification of the crude reaction mixture.

[0010] When it comes to producing a dialkylaminoalkyl (meth)acrylate, such as ADAME, by transesterification from methyl (meth)acrylate, it is difficult to envisage using a titanium alcoholate such as tetraethyl titanate, due to the gradual appearance of a white precipitate, totally insoluble in the reaction medium, which turns out to be tetramethyl titanate. Indeed, in the presence of the methanol generated during the transesterification, there is an exchange of ligands with the titanate used and formation of methyl titanates of which the insoluble tetramethyl titanate is the final product. In addition to the phenomenon of catalyst deactivation, and consequently the slowing down of the reaction kinetics, there is also fouling of the reactor and its annexes, which is not acceptable on an industrial scale.

[0011] Document EP 2099739 describes a family of catalysts based on titanium and polyol, making it possible to catalyze the synthesis of (meth)acrylic esters by transesterification, in particular, from methyl (meth)acrylate, without observing any phenomenon of catalyst deactivation and reactor fouling. These catalysts, in addition to being very active and selective, have the advantage of not allowing solids to precipitate during the reaction, unlike the aforementioned alkyl titanates which generate insoluble methyl titanate in the presence of methanol.

[0012] The organometallic catalysts used by current manufacturers of aminoalkyl (meth)acrylates produce a significant amount of Michael adducts and polymers during the reaction and purification process. In addition, the use of these organometallic catalysts generates waste that is difficult to treat and poorly developed for recovery.

[0013] In JP H04 79889, alkylaminoalkyl esters of acrylic acid or methacrylic acid were obtained by means of a transesterification reaction between a lower ester of (meth)acrylic acid and an alkylaminoalkyl alcohol, in the presence of an enzyme or a microorganism capable of asymmetrically hydrolyzing an ester. The enzyme is derived from a microorganism belonging to the genera Rhizopus, Mucor, Aspergillus, Candida, Pseudomonas, Alcaligenes, Achromobacter or Bacillus. In Example 1, dimethylaminoethyl acrylate was produced by an enzymatic reaction between methyl acrylate and dimethylaminoethanol. In Example 2, dimethylaminoethyl methacrylate was obtained enzymatically from ethyl methacrylate and dimethylaminoethanol. In both cases, the yield, calculated from the data shown in Table 2, is a maximum of 3.1%.These performance values ​​are incompatible with an industrial application of said process.

[0014] The present invention provides an improved route for manufacturing aminoalkyl (meth)acrylates, involving a bio-sourced catalyst and whose production is sustainable.

[0015] 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. It has been found that the enzymatic reaction is very selective and that products of high purity are obtained. The enzymatic reaction can also be carried out on an industrial scale.

[0016] Summary of the invention

[0017] The invention relates to an optimized process for the synthesis of dialkylaminoalcohol (meth)acrylates by transesterification of an alkyl (meth)acrylate with a dialkylaminoalcohol which uses as catalyst a supported enzyme, more particularly a lipase.

[0018] This heterogeneous catalyst makes it possible to obtain a product at a lower temperature than those usually used in organometallic catalysis, which induces better selectivity. This improvement in selectivity results in approximately 100 times fewer Michael adducts in batch and the absence of polymerization of the (meth)acrylic ester obtained. Therefore, a gain in (meth)acrylates (product sold), as well as a saving in polymerization inhibitor, usually used extensively during the synthesis of dialkylaminoalkyl (meth)acrylates. Since the inhibitors are derived from petrochemicals, limiting their use reduces the environmental impact of the manufacturing process. Michael adducts are generally cracked in order to regenerate valuable molecules. This cracking is energy-intensive because it requires high temperatures (above 150°C).Finally, the use of partially bio-sourced catalysts allows the reduction of the environmental footprint of the manufacturing process.

[0019] The optimized process features reaction conditions with very high yields, excellent selectivity and shows the potential for reuse of the catalytic charge over several consecutive batches. In addition, the supported enzyme has the advantage of being usable in a continuous process.

[0020] Detailed description of the invention

[0021] The present invention relates to a process for the synthesis of dialkylaminoalkyl acrylates and dialkylaminoalkyl methacrylates (hereinafter referred to as dialkylaminoalkyl (meth)acrylates) by transesterification, involving a so-called light (meth)acrylate of formula (1), where R1 = H or methyl, and R2 is a linear or branched, saturated or unsaturated alkyl chain containing 1 to 4 carbon atoms, and a dialkylaminoalcohol of formula (2) where R3, R4 are saturated linear or branched alkyl chains or aromatic groups, and where n is 1 to 6.

[0022] [Chem 1] [

[0023] Typically, the process according to the invention takes place in the presence of a transesterification catalyst consisting of at least one supported enzyme.

[0024] According to various embodiments, said method comprises the following characteristics, possibly combined.

[0025] The proportions between light (meth)acrylate and dialkylaminoalcohol (l) / (2) vary from 1 to 20, more particularly from 1 to 10.

[0026] Said at least one enzyme is used in immobilized form. The enzyme(s) may be immobilized chemically or physically.

[0027] The supported enzyme may be implemented as a fixed bed composed of different layers of different lipases, or in a retention basket or any other means of contact with the reactants to maintain the supported enzyme in the reactor.

[0028] Preferably, the supported enzymes used can be fixed via different methods known to those skilled in the art. For example, a fixed bed composed of different layers of different lipases can be envisaged.

[0029] According to one embodiment, said at least one enzyme belongs to the large family of carboxylic ester hydrolases EC 3.1.1.

[0030] According to one embodiment, the method takes place in the presence of a cocktail of enzymes. By "cocktail of enzymes" is meant a mixture of different lipases or esterases making it possible to increase the substrate specificity.

[0031] For example, it could be considered to use a mixture of several enzymes as catalytic load. 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.

[0032] The example of an enzyme cocktail described above is in no way limiting. According to one embodiment, the method takes place in the presence of two enzymes.

[0033] According to one embodiment, the method takes place in the presence of three enzymes.

[0034] According to one embodiment, the method takes place in the presence of an enzyme.

[0035] According to one embodiment, said enzyme is triacylglycerol lipase (EC 3.1.1.3).

[0036] According to one embodiment, said enzyme is a lipase extracted from Candida antartica.

[0037] According to one embodiment, said enzyme is Candida antarctica Lipase B (CALB). This enzyme is commercially available, for example in the form of Novozym®435.

[0038] According to one embodiment, the method according to the invention uses Lipase B from Candida antartica immobilized on a macroporous resin of poly(methyl methacrylate) type crosslinked with divinylbenzene.

[0039] The amount of supported enzyme added to the reaction medium can vary from 0.1 to 10% and preferably from 0.25 to 5% and even more preferably between 0.5 and 3% by mass relative to the sum of the masses of the light (meth)acrylate and the dialkylaminoalcohol.

[0040] According to one embodiment, the synthesis of dialkylaminoalkyl (meth)acrylate occurs without solvent.

[0041] According to one embodiment, no polymerization inhibitor is added to the reaction medium.

[0042] According to one embodiment, the reaction mixture is stabilized by the addition of a polymerization inhibitor. As polymerization inhibitors that can be used, mention may be made, for example, of phenothiazine (PTZ), hydroquinone (HQ), hydroquinone monomethyl ether (EMHQ), di-tert-butyl para-cresol (BHT), paraphenylenediamine, TEMPO (2,2,6,6-tetramethyl-l-piperidinyloxy), di-tert-butylcatechol, or TEMPO derivatives, such as OH-TEMPO, manganese acetate alone or their mixtures in all proportions, at contents in the reaction medium that may be between 50 ppm and 5000 ppm, preferably at contents between 150 ppm and 1000 ppm.

[0043] The reaction temperature can vary from 10°C to 100°C, preferably between 40°C and 70°C.

[0044] The synthesis process according to the invention can be carried out batchwise or continuously, with or without distillation of the azeotrope. During a batch experiment, the total final content of Michael adducts in the reaction medium does not exceed 0.01 moles per mole of dialkylaminoalkyl (meth)acrylate formed.

[0045] The reaction can be carried out at atmospheric pressure or under vacuum. The reaction time varies depending on the type of reaction (in a closed environment, or in batch mode with or without distillation of the light alcohol / light (meth)acrylate azeotrope).

[0046] The supported enzyme is implemented in the form of a fixed bed or maintained in the reactor by means of any type of filter. The maintenance of the enzymatic activity depends on the molar ratio between the light (meth)acrylate and the dialkylaminoalkyl. A relative yield of 30% to 60% over 10 successive cycles is observed in batch with distillation of the light alcohol / light (meth)acrylate azeotrope. In continuous operation without distillation of the light alcohol / light (meth)acrylate azeotrope, the yield can be maintained for 25 days with a maximum loss of 10%.

[0047] The process according to the invention is used in particular to prepare dimethylaminoethyl acrylate (ADAME), dimethylaminopropyl acrylate, diethylaminoethyl acrylate, tert-butylaminoethyl acrylate, dimethylaminoethyl methacrylate (MADAME).

[0048] According to one embodiment, the light alkyl (meth)acrylate is ethyl acrylate. During the synthesis, ethanol is generated, which is eliminated in the form of an azeotrope with the ethyl (meth)acrylate.

[0049] According to one embodiment, the light alkyl (meth)acrylate is methyl methacrylate. During the synthesis, methanol is generated, which is eliminated in the form of an azeotrope with the methyl (meth)acrylate.

[0050] The following examples illustrate the present invention without, however, limiting its scope. The percentages are expressed as mass percentages.

[0051] EXPERIMENTAL PART

[0052] General protocol for examples 1 to 6:

[0053] In a reactor, the supported enzyme is introduced, followed by the light (meth)acrylate, the dialkylamino alcohol and the polymerization inhibitor. The reactor is hermetically sealed and the reaction medium is stirred at 50°C for 24 hours. After returning to room temperature, the medium is filtered and analyzed by gas chromatography.

[0054] Example 1: Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435.

[0055] The reaction parameters and results obtained are shown in Table 1. [Chem 3]

[0056] [Table 1]

[0057] Example 2: Synthesis of N,N-diethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-diethylaminoethanol catalyzed by Novozym®435.

[0058] [Chem 4]

[0059] The reaction parameters and results obtained are shown in Table 2.

[0060] [Table 2]

[0061] Example 3: Synthesis of N,N-dimethylaminopropyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminopropan-1-ol catalyzed by Novozym®435.

[0062] [Chem 5]

[0063] The reaction parameters and results obtained are shown in Table 3.

[0064] [Table 3]

[0065] Example 4: Synthesis of l-methyl-2-N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminopropan-2-ol catalyzed by Novozym®435.

[0066] [Chem 6]

[0067] The reaction parameters and results obtained are shown in Table 4.

[0068] [Table 4]

[0069] Example 5: Synthesis of N,N-dimethylaminoethyl acrylate from methyl acrylate (MA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435. [Chem 7]

[0070] The reaction parameters and results obtained are shown in Table 5.

[0071] [Table 5]

[0072] Example 6: Syntheses of N,N-dimethylaminoethyl methacrylate from methyl methacrylate (MAM) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435.

[0073] [Chem 8]

[0074] The reaction parameters and results obtained are shown in Table 6.

[0075] [Table 6] These results show that:

[0076] - the yields are better in the acrylate series than in the methacrylate series (example 6 versus examples 1-5);

[0077] - the bulk on the tertiary amine function does not influence the reaction yield (example 2 versus example 1);

[0078] - the reaction works less well in the case of branched dialkylaminoalcohol than linear (example 4 versus examples 1-3).

[0079] General protocol for examples 7 to 11:

[0080] In a stirred reactor, the enzymatic catalyst is introduced followed by the light (meth)acrylate and the dialkylaminoalcohol. Phenothiazine is added to stabilize the reaction. The reactor is topped with a distillation column allowing the distillation of the light alcohol / light (meth)acrylate azeotrope. The reaction medium is stirred at 50°C for 3 hours under a pressure of 13000 Pa. After returning to ambient pressure and temperature, the reaction medium is filtered and analyzed by gas chromatography. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435.

[0081] 1.0% by mass of Novozym®435 relative to the mass of the AE / DMAE mixture is used.

[0082] Ethyl acrylate and N,N-dimethylaminoethanol are introduced in a molar ratio AE / DMAE = 3.

[0083] 2000 ppm of phenothiazine are added to stabilize the reaction. The yield obtained is 70%, with a total Michael adduct formation of 4.10' 3 moles of adducts per mole of N,N-dimethylaminoethyl acrylate formed. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435.

[0084] 2.0% by mass of Novozym®435 relative to the mass of the AE / DMAE mixture are used.

[0085] Ethyl acrylate and N,N-dimethylaminoethanol are introduced in a molar ratio

[0086] AE / DMAE = 3.

[0087] 2000 ppm of phenothiazine are added to stabilize the reaction. The yield obtained is 96%, with a total Michael adduct formation of 2.5.10 -3 moles of adducts per mole of N,N-dimethylaminoethyl acrylate formed. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435.

[0088] 1.0% by mass of Novozym®435 relative to the mass of the AE / DMAE mixture are used.

[0089] Ethyl acrylate and N,N-dimethylaminoethanol are introduced in a molar ratio

[0090] AE / DMAE = 5.

[0091] 2000 ppm of phenothiazine are added to stabilize the reaction. The yield obtained is 99%, with a total Michael adduct formation of 1.1.10-3 moles of adducts per mole of N,N-dimethylaminoethyl acrylate formed. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate

[0092] (AE) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435.

[0093] 1.5% by mass of Novozym®435 relative to the mass of the AE / DMAE mixture are used.

[0094] Ethyl acrylate and N,N-dimethylaminoethanol are introduced in a molar ratio

[0095] AE / DMAE = 3.

[0096] 200 ppm of phenothiazine are added to stabilize the reaction. The yield obtained is

[0097] 98%, no polymer was detected by size exclusion chromatography. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate

[0098] (AE) and N,N-dimethylaminoethanol (DMAE) catalyzed by Novozym®435.

[0099] 1.5% by mass of Novozym®435 relative to the mass of the AE / DMAE mixture are used.

[0100] Ethyl acrylate and N,N-dimethylaminoethanol were introduced in a molar ratio AE / DMAE = 3. No inhibitor was added to stabilize the reaction. The yield obtained was 95%, no polymer was detected by size exclusion chromatography. comparative example to examples 7 to 9. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate and N,N-dimethylaminoethanol catalyzed by ethyl titanate.

[0101] In a stirred reactor, ethyl acrylate (EA) is introduced, followed by N,N-dimethylaminoethanol (DMAE), in a molar ratio of EA / DMAE = 1.6, followed by ethyl titanate (1% by mass). 2000 ppm of phenothiazine are added to stabilize the reaction. The reactor is topped with a distillation column allowing the distillation of the EA / ethanol azeotrope. The reaction medium is stirred at 110 °C for 3 hours under a pressure of 42000 Pa. After returning to ambient pressure and temperature, the reaction medium is filtered and analyzed by gas chromatography. The yield of N,N-dimethylaminoethyl acrylate obtained is 80% and the total amount of Michael adducts is 2.9.10 1 moles of adducts per mole of N,N-dimethylaminoethyl acrylate formed. comparative example to Example 10. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate and N,N-dimethylaminoethanol catalyzed by ethyl titanate.

[0102] In a stirred reactor, ethyl acrylate (EA) is introduced, followed by N,N-dimethylaminoethanol (DMAE), in a molar ratio of EA / DMAE = 1.6, followed by ethyl titanate (1% by mass). 200 ppm of phenothiazine are added to stabilize the reaction. The reactor is topped with a distillation column allowing the distillation of the EA / ethanol azeotrope. The reaction medium is stirred at 110 °C for 3 hours under a pressure of 42000 Pa. After returning to ambient pressure and temperature, the reaction medium is filtered and analyzed by gas chromatography. The yield of N,N-dimethylaminoethyl acrylate obtained is 73% and the presence of polymers was detected by size exclusion chromatography. comparative example to Example 11. Synthesis of N,N-dimethylaminoethyl acrylate from ethyl acrylate and N,N-dimethylaminoethanol catalyzed by ethyl titanate.

[0103] In a stirred reactor, ethyl acrylate (EA) is introduced, followed by N,N-dimethylaminoethanol (DMAE), in a molar ratio AE / DMAE = 1.6, followed by ethyl titanate (1% by mass). No polymerization inhibitor was added to stabilize the reaction. The reactor is topped with a distillation column allowing the distillation of the AE / ethanol azeotrope. The reaction medium is stirred at 110°C for 3 hours under a pressure of 42000 Pa. After returning to ambient pressure and temperature, the reaction medium is filtered and analyzed by gas chromatography. The yield of N,N-dimethylaminoethyl acrylate obtained is 79% and the presence of polymers was detected by size exclusion chromatography.

[0104] Examples 7, 8 and 9 show yields of 70% to 99% with Michael adduct ratios of 1.10“ 3 at 4.10' 3moles per mole of product formed, which is approximately 100 times lower than the content of Michael adducts in Example 12 using the organometallic catalyst Ethyl titanate. This increase in selectivity is an interesting factor in industrial production. On the other hand, Examples 10 and 11 show that during low stabilization or even the absence of polymerization inhibitor, no presence of polymer was detected unlike Examples 13 and 14 using ethyl titanate as catalyst and a low content of phenothiazine or its absence in the reaction medium. In batch with distillation of the light alcohol / light (meth)acrylate azeotrope, the process according to the invention, involving at least one supported enzyme, therefore provides better selectivity of the reaction with respect to Michael additions and polymerization than the organometallic catalyst ethyl titanate.

[0105] General protocol for examples 15 to 17: Recycling of the catalytic load (supported enzyme) over several successive batches.

[0106] In a stirred reactor, ethyl acrylate is introduced, followed by N,N-dimethylaminoethyl and the enzyme catalyst. 2000 ppm of phenothiazine are added to stabilize the reaction. The reactor is topped with a distillation column allowing the distillation of the light alcohol / light acrylate azeotrope. The reaction medium is stirred at 50°C for 3 hours under a pressure of 13000 Pa. After returning to ambient pressure and temperature, the reaction medium is filtered and analyzed by gas chromatography. The catalytic charge (supported enzymes) is retained in the reactor and engaged with fresh reagents for successive syntheses.

[0107] Example 15: Successive syntheses of N,N-dimethylaminoethyl acrylate catalyzed by Novozym®435.

[0108] Ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) are introduced in an AE / DMAE molar ratio of 3 and 1.5% by mass of Novozym®435 are used as catalyst. The productivity of N,N-dimethylaminoethyl acrylate over 9 consecutive cycles is 108 g per gram of Novozym®435. The yield obtained is shown in Table 7.

[0109] [Table 7]

[0110] Example 16: Successive syntheses of N,N-dimethylaminoethyl acrylate catalyzed by Novozym®435. Ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) are introduced in an AE / DMAE molar ratio of 5 and 1.5% by mass of Novozym®435 are used as catalyst. The productivity of N,N-dimethylaminoethyl acrylate over 10 consecutive cycles is 117 g per gram of Novozym®435. The yield obtained is shown in Table 8.

[0111] [Table 8]

[0112] Example 17: Successive syntheses of N,N-dimethylaminoethyl acrylate catalyzed by Lipase CL Amano IM.

[0113] Ethyl acrylate (EA) and N,N-dimethylaminoethanol (DMAE) are introduced in an AE / DMAE molar ratio of 5 and 1.5% by mass of Lipase CL Amano IM are used as catalyst. The productivity of N,N-dimethylaminoethyl acrylate over 10 consecutive cycles is 114 g per gram of Lipase CL Amano IM. The yield obtained is shown in Table 9.

[0114] [Table 9]

[0115] The maintenance of enzymatic activity depends on the molar ratio between light (meth)acrylate and dialkylaminoalkyl. A relative yield of 30% to 60% over 10 successive cycles is observed. Example 18: Continuous synthesis of N,N-dimethylaminoethyl acrylate (ADAME) catalyzed by Novozym®435.

[0116] In a double-jacketed plug-flow reactor containing circulating silicone oil, 7.8 g of Novozym®435 supported enzyme are introduced and immobilized in the piston using cotton at the ends. The plug-flow reactor is continuously fed with a mixture of ethyl acrylate and N,N-dimethylaminoethanol in a molar ratio of 5, containing 200 ppm of phenothiazine. The feed rate is on average 14 grams / hour and the oil circulating in the double jacket of the plug-flow reactor is heated to 50 °C. The yield of the reaction carried out continuously is 68% at start-up and is maintained above 60% for 27 days. The quantity of adducts generated during this continuous reaction is of the order of 7.10 -4 at 3:10 p.m. -4 moles per mole of AD AME formed. The results obtained are shown in Table 10.

[0117] [Table 10]

Claims

CLAIMS 1. Process for the synthesis of dialkylaminoalkyl (meth)acrylate by transesterification, involving a so-called light (meth)acrylate of formula (1), where R1 = H or methyl, and R2 is a linear or branched, saturated or unsaturated alkyl chain containing 1 to 4 carbon atoms, and a dialkylaminoalcohol of formula (2) where R3, R4 are saturated linear or branched alkyl chains or aromatic groups, and where n is 1 to 6, [Chem 9] in the presence of a transesterification catalyst, characterized in that said catalyst consists of at least one supported enzyme.

2. Method according to claim 1, in which the ratio between the light (meth)acrylate and the dialkylaminoalcohol varies from 1 to 20, more particularly from 1 to 10.

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

1.

4. Method according to claim 1 to 3, taking place in the presence of a cocktail of enzymes formed from a mixture of different lipases or esterases.

5. Method according to claim 1 to 3, wherein said enzyme is triacylglycerol lipase (EC 3.1.1.3).

6. The method of claim 5, wherein said enzyme is Lipase B from Candida antartica.

7. Method according to one of claims 1 to 6, in which the quantity of supported enzyme added to the reaction medium varies from 0.1 to 10% and preferably from 0.25 to 5% and even more preferably between 0.5 and 3% by mass relative to the sum of the masses of the light acrylate and the dialkylaminoalcohol.

8. Process according to one of claims 1 to 7, in which the transesterification reaction is carried out without solvent.

9. Process according to one of claims 1 to 8, in which the reaction mixture is stabilized by the addition of a polymerization inhibitor chosen from the group: phenothiazine, hydroquinone, hydroquinone monomethyl ether, di-tert-butyl para-cresol, paraphenylenediamine, TEMPO (2,2,6,6-tetramethyl-l-piperidinyloxy), di-tert-butylcatechol, TEMPO derivatives, manganese acetate, alone or their mixtures in all proportions, at contents in the reaction medium of between 50 ppm and 5000 ppm, preferably of between 150 ppm and 1000 ppm.

10. Process according to one of claims 1 to 8, in which the transesterification reaction takes place in the absence of polymerization inhibitors.

11. Process according to one of claims 1 to 10, in which the transesterification reaction takes place batchwise with or without distillation of the light alcohol / light (meth)acrylate azeotrope.

12. Process according to one of claims 1 to 10, in which the transesterification reaction takes place continuously with or without distillation of the light alcohol / light (meth)acrylate azeotrope.

13. Method according to one of claims 1 to 12, in which the supported enzyme is implemented in the form of a fixed bed.

14. Process according to one of claims 1 to 13, for preparing dimethylaminoethyl acrylate (ADAME), dimethylaminopropyl acrylate, diethylaminoethyl acrylate, tert-butylaminoethyl acrylate, dimethylaminoethyl methacrylate (MADAME).

15. Process according to claim 11, in which the total final content of Michael adducts in the reaction medium does not exceed 0.01 moles per mole of dialkylaminoalkyl (meth)acrylate formed.

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