2-(allyloxymethyl) methyl acrylate and a method for preparing the same

Abstract

The application discloses 2-(allyloxymethyl) methyl acrylate and a preparation method thereof, and belongs to the technical field of organic synthesis. The preparation method comprises the following steps: performing esterification reaction on 2-hydroxymethyl methyl acrylate as raw material in the presence of an acid-binding agent and sulfuryl chloride to obtain an intermediate sulfonic acid ester; then performing reaction on allyl alcohol as raw material and an alkali to prepare sodium allyl alcohol; finally, performing condensation reaction on the intermediate sulfonic acid ester and the sodium allyl alcohol to obtain the product; wherein the mass ratio of 2-hydroxymethyl methyl acrylate, sulfuryl chloride, the acid-binding agent, allyl alcohol and the alkali is 1:(1.0-1.2):(1.0-1.2):(1.0-3.0):(1.0-1.5). The preparation method of 2-(allyloxymethyl) methyl acrylate can improve the total reaction yield and the purity of the product, and is convenient for being applied to large-scale industrial production.

Description

Technical Field

[0001] This invention relates to the field of organic synthesis technology, and in particular to a methyl 2-(allyloxymethyl)acrylate and its preparation method. Background Technology

[0002] Acrylic esters are commonly used UV-curable reactive resins that can polymerize under UV catalysts. Their monomers and oligomers are suitable for use in energetic adhesives, coatings, inks, and resins. 2-(allyloxymethyl)acrylate can be added to blue photosensitive resins for color filters to improve their ITO sputtering suitability and pigment dispersion. It can also be added to electrolytes to improve electrolyte loss during high-temperature energy storage in lithium batteries and capacity loss during subsequent cycles, thus extending battery life. Therefore, 2-(allyloxymethyl)acrylate has wide applications in photosensitive resins and lithium battery electrolyte additives.

[0003] In the prior art, the patent EP2578565A1 published in 2011, "ALPHA-SUBSTITUTED ACRYLATEESTERS, COMPOSITION CONTAINING SAME AND METHOD FOR PRODUCING THE -SUBSTITUTEDACRYLATE ESTERS", mentions the preparation of 2-(allyloxymethyl)acrylate by reacting methyl 2-hydroxymethacrylate with allyl alcohol. This synthesis process requires vacuum distillation, which is complicated. The reaction temperature of 100°C and the reaction time of more than 10 hours make the double bonds easy to polymerize, resulting in more side reactions and increased difficulty in product separation. The yield is only 65%, which restricts its large-scale industrial production. Another patent published in 2014, JP2014-162784A, entitled "Preparation Method of α-substituted methyl acrylate compounds", also uses the reaction of 2-hydroxymethyl acrylate with allyl alcohol to prepare 2-(allyloxymethyl) acrylate. However, this synthesis process also requires a distillation process, and the reaction temperature is reduced to 80°C and the reaction time is extended to 20 hours. However, the yield of this method is only increased to 73.3%, which is difficult to meet the needs of high-end applications. Summary of the Invention

[0004] This invention provides methyl 2-(allyloxymethyl)acrylate and its preparation method to improve the overall reaction yield and product purity, making it suitable for large-scale industrial production.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: This invention provides a method for preparing methyl 2-(allyloxymethyl)acrylate, comprising the following steps: S1: Mix methyl 2-hydroxymethacrylate, acid-binding agent, and solvent evenly, and cool to -5℃ to -5℃; S2: Sulfonyl chloride is added dropwise to the mixture obtained in step S1 at 0℃-15℃, and then the reaction is maintained at 0℃-15℃ for 3-5 hours. The insoluble matter is removed by filtration to obtain the intermediate sulfonate solution. S3: Mix allyl alcohol and solvent evenly, and cool to -5℃ to -5℃; add alkali in batches at 0℃ to 15℃, and after the addition is complete, raise to room temperature and react for 3-5 hours to obtain sodium allyl alcohol mixture. S4: At 0℃ to 15℃, the sodium propylene oxide mixture obtained in step S3 is added to the intermediate sulfonate solution obtained in step S2, and then the temperature is raised to 0℃-50℃ for condensation reaction for 8-24 hours to obtain the mixture. S5: After the condensation reaction is completed, methanol is added to the mixture obtained in step S4 and stirred for 3-5 hours. The mixture is then filtered, and the filtrate is washed with water, separated, washed with saturated brine to remove the organic phase, the solvent is recovered under reduced pressure, and distilled to obtain the target product methyl 2-(allyloxymethyl)acrylate. The molar ratio of methyl 2-hydroxymethyl acrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali is 1:(1.0-1.2):(1.0-1.2):(1.0-3.0):(1.0-1.5).

[0006] Furthermore, the molar ratio of methyl 2-hydroxymethacrylate, sulfonyl chloride, acid-binding agent, allyl alcohol and alkali is 1:1.05:1.1:(1.05-1.1):(1.05-1.1).

[0007] Furthermore, the acid-binding agent is at least one of triethylamine, pyridine, and adsorption resin.

[0008] Furthermore, the acid-binding agent is triethylamine or pyridine.

[0009] Furthermore, the sulfonyl chloride is at least one of methylsulfonyl chloride and phenylsulfonyl chloride.

[0010] Furthermore, in steps S1 and S3, the solvent is selected from at least one of aromatic hydrocarbons, aliphatic hydrocarbons, and aliphatic ethers.

[0011] Further, in step S3, the alkali is at least one of sodium hydride and metallic sodium.

[0012] Furthermore, the condensation reaction in step S4 is carried out at a temperature of 25°C to 50°C for 10 to 24 hours.

[0013] In another aspect, the present invention provides methyl 2-(allyloxymethyl)acrylate, prepared by the aforementioned method, wherein the structural formula of the methyl 2-(allyloxymethyl)acrylate is shown in Formula I: Formula I.

[0014] The beneficial effects of this invention are: (1) The method for preparing methyl 2-(allyloxymethyl)acrylate disclosed in this invention, by first preparing a sulfonate intermediate and then condensing it with pre-prepared sodium propylene oxide at low temperature, successfully avoids the ester group side reaction caused by the direct condensation of methyl 2-hydroxymethylacrylate under strong base, and also inhibits the polymerization side reaction caused by high temperature, thereby reducing the generation of impurities from the source and reducing the difficulty of product separation. (2) The product post-processing is simple and does not require complicated vacuum distillation. High-purity products can be obtained through conventional distillation, which is suitable for industrial production. (3) This method achieves a total product yield of over 80% and a product purity of over 95%, meeting application requirements. Attached Figure Description To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 The image shows the 1H NMR spectrum (¹H-NMR) of methyl 2-(allyloxymethyl)acrylate prepared in Example 1 of this invention. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Example 1 2-(allyloxymethyl)acrylate, the synthetic route is shown below:

[0018] A method for preparing methyl 2-(allyloxymethyl)acrylate specifically includes the following steps: S1: Weigh 23.21g (0.2mol) of methyl 2-hydroxymethacrylate, 17.4g (0.22mol) of pyridine and 100g of petroleum ether, mix them evenly, and then cool the mixture to -5-5℃; S2: Add 24.05 g (0.21 mol) of methanesulfonyl chloride dropwise to the mixture obtained in step S1 at a controlled temperature of 0-15℃ for 3 hours. After the addition is completed, react at 0-15℃ for 3 hours, filter to remove insoluble matter, and the filtrate is the intermediate sulfonate solution. S3: Mix 12.76g (0.22mol) of allyl alcohol and 20g of petroleum ether evenly and cool to -5-5℃; add 5.06g (0.22mol) of metallic sodium in 6 portions, control the temperature at -5-0℃, and after the addition is complete, raise the temperature to room temperature and react for 3h to obtain a sodium allyl alcohol solution for later use; In this example, the molar ratio of methyl 2-hydroxymethacrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali is 1:1.05:1.1:1.1:1.1; S4: The sodium propylene oxide solution obtained in step S3 is added dropwise to the intermediate sulfonate solution obtained in step S2 at a controlled temperature of 0-15℃, and then the temperature is raised to 40℃ for condensation reaction, and the reaction time is 10h. S5: After the condensation reaction was completed, 10g of methanol was added to the mixture obtained in step S4 and stirred for 3 hours. The mixture was then filtered, deionized water was added, and the liquid was separated. The organic phase was washed with saturated brine, the solvent was recovered under reduced pressure, and the mixture was distilled to obtain 26.13g of a colorless and transparent liquid. The NMR spectrum of the obtained product was analyzed, and the NMR spectrum is shown below. Figure 1 As shown, 1 ¹H NMR (CDCl₃) 3.754 (s, 3H), 4.053–4.114 (m, 2H), 4.473 (s, 2H), 5.181–5.407 (m, 2H), 5.794–5.994 (m, 2H), 6.334 (d, 1H), confirming the product as methyl 2-(allyloxymethyl)acrylate; the product purity was 95.6%, and the yield was 80%.

[0019] Example 2 A method for preparing methyl 2-(allyloxymethyl)acrylate includes the following steps: S1: Weigh 23.21g (0.2mol) of methyl 2-hydroxymethacrylate, 22.26g (0.22mol) of triethylamine and 100g of tetrahydrofuran, mix them evenly, and then cool the mixture to -5-5℃; S2: Add 24.05 g (0.21 mol) of methanesulfonyl chloride dropwise to the mixture obtained in step S1 at a controlled temperature of 0-15℃ for 3 hours. After the addition is completed, react at 0-15℃ for 3 hours, filter to remove insoluble matter, and the filtrate is the intermediate sulfonate solution. S3: Mix 12.76g (0.22mol) of allyl alcohol and 20g of tetrahydrofuran evenly, then cool to -5-5℃; add 8.8g of 60% sodium hydride (0.22mol) in 6 portions, controlling the temperature at -5-0℃, and then raise the temperature to room temperature for 3h to obtain a sodium allyl alcohol mixture for later use; In this example, the molar ratio of methyl 2-hydroxymethyl acrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali is 1:1.05:1.1:1.1:1.1; S4: Add the sodium propylene oxide mixture obtained in step S3 to the intermediate sulfonate solution obtained in step S2 under controlled temperature of 0-15℃ and stirring, and then raise the temperature to 32℃ for condensation reaction. The reaction time is 16h. S5: After the condensation reaction is completed, the mixture obtained in step S4 is added to 10g of methanol and stirred for 3h. After filtration, deionized water is added, the mixture is separated, the organic phase is washed with saturated brine, the solvent is recovered under reduced pressure, and distilled to obtain 26.45g of colorless and transparent liquid, which is methyl 2-(allyloxymethyl)acrylate with a content of 98% and a yield of 83%.

[0020] Example 3 A method for preparing methyl 2-(allyloxymethyl)acrylate includes the following steps: S1: Weigh 23.21g (0.2mol) of methyl 2-hydroxymethacrylate, 22.26g (0.22mol) of triethylamine and 100g of toluene, mix them evenly, and then cool the mixture to -5 to -5℃; S2: Add 24.05 g (0.21 mol) of methanesulfonyl chloride dropwise to the mixture obtained in step S1 at a controlled temperature of 0-15℃ for 3 hours. After the addition is completed, react at 0-15℃ for 3 hours, filter to remove insoluble matter, and the filtrate is the intermediate sulfonate solution. S3: Mix 12.19g (0.21mol) of allyl alcohol and 20g of tetrahydrofuran evenly, then cool to -5-5℃; add 8.4g of 60% sodium hydride (0.21mol) in 6 portions, controlling the temperature at -5-0℃, and then raise the temperature to room temperature for 3h to obtain a sodium allyl alcohol mixture for later use; In this example, the molar ratio of methyl 2-hydroxymethyl acrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali is 1:1.05:1.1:1.05:1.05; S4: Add the sodium propylene oxide mixture obtained in step S3 to the intermediate sulfonate solution obtained in step S2 under controlled temperature of 0-5℃ and stirring, and then raise the temperature to 25℃ for condensation reaction for 24 hours. S5: After the condensation reaction is completed, the mixture obtained in step S4 is added to 10g of methanol and stirred for 3h. After filtration, deionized water is added, the mixture is separated, the organic phase is washed with saturated brine, the solvent is recovered under reduced pressure, and distilled to obtain 26.87g of colorless and transparent liquid, which is methyl 2-(allyloxymethyl)acrylate with a content of 99.1% and a yield of 85.8%.

[0021] Comparative Example 1 A method for preparing methyl 2-(allyloxymethyl)acrylate; The difference between this comparative example and Example 3 is that in this comparative example, triethylamine is replaced with an adsorption resin, and the amount of allyl alcohol and sodium hydride in step S3 is increased. The preparation method specifically includes the following steps: S1: Weigh 23.21g (0.2mol) of methyl 2-hydroxymethacrylate, 20g of adsorption resin and 100g of toluene and mix them evenly. Then cool the mixture to -5 to -5℃. S2: Add 24.05 g (0.21 mol) of methanesulfonyl chloride dropwise to the mixture obtained in step S1 at a controlled temperature of 0-15℃ for 3 hours. After the addition is completed, react at 0-15℃ for 3 hours, filter to remove insoluble matter, and the filtrate is the intermediate sulfonate solution. S3: Add 34.85g (0.6mol) of allyl alcohol and then cool to -5-5℃; add 9.6g of 60% sodium hydride (0.24mol) in 6 portions, maintaining the temperature at -5-0℃, and then raise the temperature to room temperature for 3 hours to obtain a sodium allyl alcohol mixture for later use; In this comparative example, the molar ratio of methyl 2-hydroxymethyl acrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali is 1:1.05:1.0:3.0:1.2; S4: Add the sodium propylene oxide mixture obtained in step S3 to the intermediate sulfonate solution obtained in step S2 under controlled temperature of 0-15℃ and stirring, and then raise the temperature to 50℃ for condensation reaction for 8 hours. S5: After the condensation reaction is completed, the mixture obtained in step S4 is added to 10g of methanol and stirred for 5h. After filtration, deionized water is added, the mixture is separated, the organic phase is washed with saturated brine, the solvent is recovered under reduced pressure, and distilled to obtain 23.5g of colorless and transparent liquid, which is methyl 2-(allyloxymethyl)acrylate with a content of 97% and a yield of 73%.

[0022] Comparative Example 2 A method for preparing methyl 2-(allyloxymethyl)acrylate; The comparative example differs from Example 1 in that, in this comparative example, methyl 2-hydroxymethacrylate is replaced with allyl alcohol in step S1, and methyl 2-hydroxymethacrylate is replaced with allyl alcohol in step S3. The preparation method specifically includes the following steps: S1: Weigh 12.76g (0.22mol) of allyl alcohol, 17.4g (0.22mol) of pyridine and 100g of petroleum ether solvent, mix them evenly, and then cool the mixture to -5-5℃; S2: 24.05 g (0.21 mol) of methanesulfonyl chloride was added dropwise to the mixture obtained in step S1 at a controlled temperature of 0-15℃ for 3 hours. After the addition was completed, the mixture was reacted at 0-15℃ for 3 hours. The insoluble matter was removed by filtration, and the filtrate was the intermediate sulfonate solution. The molar ratio of methyl 2-hydroxymethacrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali was 1:1.05:1.1:1.1:1.0.

[0023] S3: Mix 23.21 g (0.2 mol) of methyl 2-hydroxymethacrylate and 20 g of petroleum ether evenly and cool to -5-5℃; add 4.6 g (0.20 mol) of metallic sodium in 6 portions, control the temperature at -5-0℃, and after the addition is complete, raise the temperature to room temperature and react for 3 hours to obtain sodium alkoxide solution for later use; S4: The sodium alkoxide solution obtained in step S3 is added dropwise to the intermediate sulfonate solution obtained in step S2 at a controlled temperature of 0-15℃, and then the temperature is raised to 40℃ for condensation reaction, and the reaction time is 10h. S5: After the condensation reaction is completed, the mixture obtained in step S4 is added to 10g of methanol and stirred for 3h. After filtration, deionized water is added, the mixture is separated, the organic phase is washed with saturated brine, the solvent is recovered under reduced pressure, and distilled to obtain 15.62g of colorless and transparent liquid, which is methyl 2-(allyloxymethyl)acrylate with a content of 60% and a yield of 30%.

[0024] Results Analysis: The results from Examples 1, 2, and 3 show that this preparation method achieves a purity of over 95% and a yield of over 80% for methyl 2-(allyloxymethyl)acrylate. Specifically, Example 1 uses a pyridine / sodium metal combination, undergoing a condensation reaction at 40°C, yielding a product with a purity of 95.6% and a yield of 80%. Example 2 replaces the acid-binding agent with triethylamine, the base with sodium hydride, and lowers the condensation temperature to 32°C, increasing the product purity to 98% and the yield to 83%. Further optimization is achieved in Example 3, where, based on the triethylamine / sodium hydride combination, the amount of sodium alkoxide is precisely controlled, and the condensation temperature is further lowered to 25°C. Under these conditions, the best results are obtained: a product purity of 99.1% and a yield of 85.8%.

[0025] This indicates that optimizing reaction conditions can further improve product quality and efficiency. In Examples 2 and 3, the acid-binding agent in step S1 of Example 1 was replaced with triethylamine, and the base in step S3 was replaced with sodium hydride instead of metallic sodium. At the same time, the temperature of the condensation reaction in step S4 was lowered. These adjustments increased the product content from 95.6% to 98% and even 99.1%, and the yield also steadily increased from 80% to 83% and 85.8%, respectively. The product content and yield were significantly improved. This trend shows that using a reagent combination with matching activity (triethylamine / sodium hydride) and implementing milder condensation reaction conditions can effectively suppress side reactions such as double bond polymerization, which is an important factor in improving reaction selectivity and yield.

[0026] A comparison of the results of Example 1 and Comparative Example 2 shows that when the substrates methyl 2-hydroxymethyl acrylate and allyl alcohol were interchanged in steps S1 and S3 of Example 2 and Comparative Example 2, the final product content decreased to 60%, and the yield dropped significantly to 30%. This result confirms that if methyl 2-hydroxymethyl acrylate is used to prepare sodium alkoxide under strongly alkaline conditions, the ester group in its molecule is very reactive, and a self-condensation reaction will occur during the preparation of sodium alkoxide. The byproducts produced not only affect the subsequent condensation reaction with sulfonate esters, but also make the separation and purification of the final product extremely difficult, resulting in a decrease in content and yield. Therefore, methyl 2-hydroxymethyl acrylate can only be used to prepare sulfonate ester intermediates, while allyl alcohol is suitable for preparing sodium alkoxide nucleophiles. This specific sequence of steps is a key prerequisite for the success of this method.

[0027] A comparison of the results of Example 3 and Comparative Example 1 shows that replacing the acid-binding agent in step S1 with an adsorption resin, increasing the amount of sodium alkoxide in step S3, and increasing the condensation reaction temperature in step S4 significantly reduced the yield to 73%. This result can be attributed to the fact that excess sodium alkoxide, at higher reaction temperatures, undergoes unnecessary side reactions with the intermediate sulfonate ester or the methyl acrylate group in the product molecule, thereby reducing the net yield of the target product.

[0028] A comparison of the results of Example 1 and Example 3 shows that Example 3 reduces the amount of sodium alkoxide in step S3 and lowers the condensation reaction temperature in step S4, which can increase the yield by more than 85%.

[0029] As can be seen from Examples 1-3, the process route adopted in this application, which involves first preparing a sulfonate intermediate and then performing low-temperature condensation with pre-prepared sodium propylene oxide, can significantly reduce the generation of polymerization byproducts, reduce the difficulty of product separation, and improve product yield. It is suitable for the industrial production of high-purity methyl 2-(allyloxymethyl)acrylate. The total yield of the target product synthesized by this method can be increased to a maximum of 85.8%, and the purity of the product can reach a maximum of 99.1%.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing methyl 2-(allyloxymethyl)acrylate, characterized in that, Includes the following steps: S1: Mix methyl 2-hydroxymethacrylate, acid-binding agent, and solvent evenly, and cool to -5℃ to -5℃; S2: Sulfonyl chloride is added dropwise to the mixture obtained in step S1 at 0℃-15℃, and then the reaction is maintained at 0℃-15℃ for 3-5 hours. The insoluble matter is removed by filtration to obtain the intermediate sulfonate solution. S3: Mix allyl alcohol and solvent evenly, and cool to -5℃ to -5℃; add alkali in batches at 0℃ to 15℃, and after the addition is complete, raise to room temperature and react for 3-5 hours to obtain sodium allyl alcohol mixture. S4: At 0℃ to 15℃, the sodium propylene oxide mixture obtained in step S3 is added to the intermediate sulfonate solution obtained in step S2, and then the temperature is raised to 0℃-50℃ for condensation reaction for 8-24 hours to obtain the mixture. S5: After the condensation reaction is completed, methanol is added to the mixture obtained in step S4 and stirred for 3-5 hours. The mixture is then filtered, and the filtrate is washed with water, separated, washed with saturated brine to remove the organic phase, the solvent is recovered under reduced pressure, and distilled to obtain the target product methyl 2-(allyloxymethyl)acrylate. The molar ratio of methyl 2-hydroxymethyl acrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali is 1:(1.0-1.2):(1.0-1.2):(1.0-3.0):(1.0-1.5).

2. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 1, characterized in that, The molar ratio of methyl 2-hydroxymethacrylate, sulfonyl chloride, acid binder, allyl alcohol and alkali is 1:1.05:1.1:(1.05-1.1):(1.05-1.1).

3. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 1, characterized in that, The acid-binding agent is at least one of triethylamine, pyridine, and adsorption resin.

4. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 3, characterized in that, The acid-binding agent is triethylamine or pyridine.

5. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 1, characterized in that, The sulfonyl chloride is at least one of methylsulfonyl chloride and phenylsulfonyl chloride.

6. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 5, characterized in that, The sulfonyl chloride is methylsulfonyl chloride.

7. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 1, characterized in that, In steps S1 and S3, the solvent is selected from at least one of aromatic hydrocarbons, aliphatic hydrocarbons, and aliphatic ethers.

8. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 1, characterized in that, In step S3, the alkali is at least one of sodium hydride and metallic sodium.

9. The method for preparing methyl 2-(allyloxymethyl)acrylate according to claim 1, characterized in that, The condensation reaction in step S4 is carried out at a temperature of 25°C to 50°C for 10 to 24 hours.

10. A methyl 2-(allyloxymethyl)acrylate, characterized in that, The methyl 2-(allyloxymethyl)acrylate prepared by the method described in claim 1 has the structural formula shown in Formula I: Equation I.

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