Vanyl butyl ether and synthesis method thereof

Abstract

The invention discloses vanillyl butyl ether and a synthesis method thereof, and relates to the technical field of synthesis of vanillyl butyl ether.The synthesis method of vanillyl butyl ether comprises the following steps that S1, vanillyl alcohol is prepared; s2, adding vanillyl alcohol prepared in the step S1, n-butyl alcohol and a catalyst into a reaction kettle, and uniformly stirring to react, so as to obtain a mixed solution after the reaction is completed; s3, filtering the mixed solution prepared in S2, pretreating filtrate, and extracting an organic phase in the filtrate; s4, carrying out primary reduced pressure distillation on the organic phase extracted in S3 to obtain a vanillyl butyl ether crude product and n-butyl alcohol, then recovering n-butyl alcohol, and carrying out secondary reduced pressure distillation on the vanillyl butyl ether crude product to obtain vanillyl butyl ether; the whole synthesis method is low in raw material cost, mild in reaction condition, simple in process and small in wastewater generation amount, recycling of the catalyst and the solvent is achieved, the prepared vanillyl butyl ether is large in yield and high in purity, a brand new solution is provided for efficient and green production of the vanillyl butyl ether, and industrial popularization is facilitated.

Description

Technical Field

[0001] This invention relates to the field of vanillyl butyl ether synthesis technology, specifically to a vanillyl butyl ether and its synthesis method. Background Technology

[0002] Vanillyl butyl ether is a chemical substance with a special thermosensitive effect and has wide applications in the food, cosmetics and pharmaceutical fields.

[0003] Existing synthesis processes for vanillyl butyl ether mainly involve the etherification reaction of vanillin with n-butanol. Chinese invention publication CN114933515A discloses a highly efficient method for synthesizing vanillyl butyl ether, using one or more of heteropoly acids, phosphorylated SiO2, and sulfated SiO2 as catalysts, and achieving continuous production via a fixed-bed reactor. However, the active centers of these catalysts are easily deactivated, and the process conditions are harsh (nitrogen protection, high reaction temperature, vacuum distillation, etc.). Chinese invention publication CN108658734A discloses a process for producing vanillin butyl ether, which uses anhydrous sodium sulfate as a catalyst. However, anhydrous sodium sulfate only has a water-absorbing effect and needs to be added in four separate steps, making the operation cumbersome and the reaction cycle long. Furthermore, Chinese invention CN113754520A discloses a method for synthesizing vanillin butyl ether using sodium bisulfate as a catalyst. However, this catalyst has low activity, requires excessive addition, cannot be recovered after the reaction, and generates wastewater.

[0004] In summary, although some progress has been made in the synthesis of vanillyl butyl ether in the existing technology, key issues such as catalyst performance, reaction efficiency, and catalyst recovery have not been fundamentally solved. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a vanillyl butyl ether and its synthesis method, so as to solve the problems of poor catalyst performance, low reaction efficiency and insufficient catalyst recovery in the synthesis methods of vanillyl butyl ether in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for synthesizing vanillyl butyl ether includes the following steps:

[0008] S1. Preparation of vanillin;

[0009] S2. Vanillin prepared in S1, n-butanol, and catalyst are added to a reaction vessel and stirred until homogeneous to carry out the reaction. After the reaction is completed, a mixed solution is obtained.

[0010] S3. Filter the mixed solution prepared in S2, pretreat the filtrate, and then extract the organic phase from the filtrate;

[0011] S4. The organic phase extracted in S3 is subjected to a first vacuum distillation to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol is recovered and the crude vanillyl butyl ether is subjected to a second vacuum distillation to obtain vanillyl butyl ether.

[0012] Preferably, in step S1, the specific preparation method of vanillin includes the following steps:

[0013] S11. Mix sodium hydroxide, desalinated water and vanillin and stir to react to form solution a;

[0014] S12. Continue stirring solution a prepared in S11, and add sodium borohydride to react and form solution b;

[0015] S13. Add hydrochloric acid to solution b prepared in S12 to adjust to neutral, then filter and wash to obtain vanillin.

[0016] Preferably, in step S11, the mass ratio of sodium hydroxide to the volume ratio of demineralized water is 1:10 to 1:20, and the molar ratio of vanillin to sodium hydroxide is 1:0.5 to 1:1.5.

[0017] Preferably, in step S12, the molar ratio of sodium borohydride to vanillin is 0.5:1 to 1.2:1, the stirring speed is 50 to 500 r / min, the reaction temperature is 20 to 40°C, and the reaction time is 1 to 3 h.

[0018] Preferably, in step S13, the washing process uses demineralized water.

[0019] Preferably, in step S2, the mass ratio of vanillin to n-butanol is 1:2 to 1:10, the mass ratio of vanillin to catalyst is 1:1.23 to 1:1.30, and the catalyst is one of montmorillonite / silica gel supported phosphotungstic acid, montmorillonite / silica gel supported styrene cation exchange resin, and montmorillonite / silica gel supported ZSM-5 molecular sieve, wherein the mass ratio of montmorillonite / silica gel to phosphotungstic acid is 1:0.005 to 1:0.1, the mass ratio of montmorillonite / silica gel to styrene cation exchange resin is 1:0.008 to 1:0.18, and the mass ratio of montmorillonite / silica gel to ZSM-5 molecular sieve is 1:0.008 to 1:0.2.

[0020] Preferably, in step S2, the stirring speed is 50–350 r / min, the reaction temperature is 30–100 °C, and the reaction time is 3–16 h.

[0021] Preferably, in step S3, the pretreatment is carried out by adding saturated saline solution and sodium bicarbonate to the mixed solution and stirring at 50-350 r / min for 0.5-1.5 h.

[0022] Preferably, in step S4, the temperature of the first vacuum distillation is 50-110℃ and the time is 0.5-5h, and the temperature of the second distillation is 120-180℃ and the time is 0.5-3.5h.

[0023] The present invention also provides a vanillyl butyl ether, which is prepared by the above-described synthesis method.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. This invention uses montmorillonite / silica gel supported phosphotungstic acid, montmorillonite / silica gel supported styrene cation exchange resin, or montmorillonite / silica gel supported ZSM-5 molecular sieve as catalysts. By utilizing the layered structure of montmorillonite and the high specific surface area of ​​silica gel, highly dispersed loading of phosphotungstic acid, styrene cation exchange resin, and ZSM-5 molecular sieve can be achieved, which can significantly improve the catalytic activity and stability of the catalyst, improve the reaction efficiency and reaction progress. At the same time, montmorillonite and silica gel can adsorb water to generate water, eliminating the need for additional desiccant. Furthermore, after the reaction is completed, the filter residue (i.e., the catalyst) can be regenerated simply by washing and drying, which is beneficial for the recycling and reuse of the catalyst and avoids the generation of solid waste.

[0026] 2. This invention employs a double vacuum distillation technique, which significantly reduces energy consumption and greatly improves product purity. Furthermore, the entire synthesis method features low raw material costs, mild reaction conditions, simple processes, and minimal wastewater generation. It also enables the recovery and reuse of catalysts and solvents. Moreover, the final product, vanillyl butyl ether, has a high yield and high purity, providing a novel solution for the efficient and green production of vanillyl butyl ether and facilitating its industrialization.

[0027] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Detailed Implementation

[0028] To make the technical means, creative features, objectives, and effects of this invention clearer and easier to understand, the invention will be further described below in conjunction with specific embodiments:

[0029] Example 1

[0030] S1. Add 456g vanillin, 120g sodium hydroxide and 1.85L deionized water to the reactor and stir continuously at 350r / min. Then add 57g sodium borohydride and react at 20℃ for 1h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0031] S2. Take 154g of vanillin prepared in S1, 308g of n-butanol and 189g of silica-supported phosphotungstic acid and add them to the reaction vessel, wherein the mass ratio of silica to phosphotungstic acid is 1:0.041. React at 350r / min and 65℃ for 8h to obtain a mixed solution.

[0032] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 280 r / min for 1 h.

[0033] S4. The organic phase extracted in S3 was subjected to a first vacuum distillation at 50°C for 2 hours to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol was recovered, and the crude vanillyl butyl ether was subjected to a second vacuum distillation at 160°C for 2.5 hours to obtain vanillyl butyl ether.

[0034] Example 2

[0035] S1. Add 456g vanillin, 60g sodium hydroxide and 0.6L deionized water to the reaction vessel and stir continuously at 50r / min. Then add 80g sodium borohydride and react at 40℃ for 3h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0036] S2. Take 154g of vanillin prepared in S1, 1540g of n-butanol and 200g of silica-supported phosphotungstic acid and add them to the reaction vessel, wherein the mass ratio of silica to phosphotungstic acid is 1:0.1. React at 100℃ for 3h with stirring speed of 200r / min to obtain a mixed solution.

[0037] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 350 r / min for 0.5 h.

[0038] S4. The organic phase extracted in S3 is subjected to a first vacuum distillation at 110℃ for 0.5 h to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol is recovered, and the crude vanillyl butyl ether is subjected to a second vacuum distillation at 120℃ for 3.5 h to obtain vanillyl butyl ether.

[0039] Example 3

[0040] S1. Add 456g vanillin, 180g sodium hydroxide and 3.6L deionized water to a reaction vessel and stir continuously at 500r / min. Then add 136.8g sodium borohydride and react at 30℃ for 2h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0041] S2. Take 154g of vanillin prepared in S1, 1000g of n-butanol and 195g of montmorillonite-supported phosphotungstic acid and add them to the reaction vessel, wherein the mass ratio of montmorillonite to phosphotungstic acid is 1:0.005. React at 80℃ for 16h with stirring speed of 50r / min to obtain a mixed solution.

[0042] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 50 r / min for 1.5 h.

[0043] S4. The organic phase extracted in S3 is subjected to a first vacuum distillation at 80°C for 3 hours to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol is recovered, and the crude vanillyl butyl ether is subjected to a second vacuum distillation at 180°C for 0.5 hours to obtain vanillyl butyl ether.

[0044] Example 4

[0045] S1. Add 456g vanillin, 100g sodium hydroxide and 1.2L deionized water to a reaction vessel and stir continuously at 300r / min. Then add 72g sodium borohydride and react at 25℃ for 2h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0046] S2. Take 154g of vanillin prepared in S1, 500g of n-butanol and 191g of silica-supported styrene cation exchange resin and add them to the reactor. The mass ratio of silica to styrene cation exchange resin is 1:0.082. React at 90℃ for 10h with stirring speed of 230r / min to obtain a mixed solution.

[0047] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 150 r / min for 1 h.

[0048] S4. The organic phase extracted in S3 is subjected to a first vacuum distillation at 100℃ for 1 h to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol is recovered, and the crude vanillyl butyl ether is subjected to a second vacuum distillation at 140℃ for 3 h to obtain vanillyl butyl ether.

[0049] Example 5

[0050] S1. Add 456g vanillin, 80g sodium hydroxide and 0.8L deionized water to the reaction vessel and stir continuously at 350r / min. Then add 100g sodium borohydride and react at 40℃ for 1h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0051] S2. Take 154g of vanillin prepared in S1, 800g of n-butanol and 198g of silica-supported styrene cation exchange resin and add them to the reactor. The mass ratio of silica to styrene cation exchange resin is 1:0.18. React at 70℃ for 14h with stirring speed of 300r / min to obtain a mixed solution.

[0052] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 100 r / min for 0.6 h.

[0053] S4. The organic phase extracted in S3 was subjected to a first vacuum distillation at 70°C for 0.6 h to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol was recovered, and the crude vanillyl butyl ether was subjected to a second vacuum distillation at 150°C for 1 h to obtain vanillyl butyl ether.

[0054] Example 6

[0055] S1. Add 456g vanillin, 130g sodium hydroxide and 1.5L deionized water to a reaction vessel and stir continuously at 200r / min. Then add 126g sodium borohydride and react at 32℃ for 2h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0056] S2. Take 154g of vanillin prepared in S1, 850g of n-butanol and 196g of montmorillonite-supported styrene cation exchange resin and add them to the reactor, wherein the mass ratio of montmorillonite to styrene cation exchange resin is 1:0.008. React at 75℃ for 15h with stirring speed of 350r / min to obtain a mixed solution.

[0057] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 150 r / min for 0.8 h.

[0058] S4. The organic phase extracted in S3 is subjected to a first vacuum distillation at 90℃ for 1.5 h to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol is recovered, and the crude vanillyl butyl ether is subjected to a second vacuum distillation at 170℃ for 1.5 h to obtain vanillyl butyl ether.

[0059] Example 7

[0060] S1. Add 456g vanillin, 150g sodium hydroxide and 2.58L deionized water to a reaction vessel and stir continuously at 150r / min. Then add 130g sodium borohydride and react at 35℃ for 2h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0061] S2. Take 154g of vanillin prepared in S1, 1300g of n-butanol and 199g of silica-supported ZSM-5 molecular sieve and add them to the reaction vessel, wherein the mass ratio of silica to ZSM-5 molecular sieve is 1:0.088. React at 150r / min and 66℃ for 15h to obtain a mixed solution.

[0062] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 200 r / min for 1.2 h.

[0063] S4. The organic phase extracted in S3 was subjected to a first vacuum distillation at 60°C for 2.3 h to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol was recovered, and the crude vanillyl butyl ether was subjected to a second vacuum distillation at 165°C for 2 h to obtain vanillyl butyl ether.

[0064] Example 8

[0065] S1. Add 456g vanillin, 70g sodium hydroxide and 0.85L deionized water to a reaction vessel and stir continuously at 400r / min. Then add 84g sodium borohydride and react at 40℃ for 3h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0066] S2. Take 154g of vanillin prepared in S1, 1250g of n-butanol and 197g of montmorillonite-supported ZSM-5 molecular sieve and add them to the reaction vessel, wherein the mass ratio of montmorillonite to ZSM-5 molecular sieve is 1:0.2. React at 50℃ for 13h with stirring speed of 80r / min to obtain a mixed solution.

[0067] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 250 r / min for 1.5 h.

[0068] S4. The organic phase extracted in S3 is subjected to a first vacuum distillation at 100℃ for 4 hours to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol is recovered, and the crude vanillyl butyl ether is subjected to a second vacuum distillation at 130℃ for 3 hours to obtain vanillyl butyl ether.

[0069] Example 9

[0070] S1. Add 456g vanillin, 90g sodium hydroxide and 0.78L deionized water to the reaction vessel and stir continuously at 450r / min. Then add 110g sodium borohydride and react at 40℃ for 3h. Add hydrochloric acid to adjust the pH to 7, then filter and wash with deionized water to obtain vanillin.

[0071] S2. Take 154g of vanillin prepared in S1, 1400g of n-butanol and 200g of silica-supported ZSM-5 molecular sieve and add them to the reaction vessel, wherein the mass ratio of silica to ZSM-5 molecular sieve is 1:0.008. React at 30℃ for 6h with stirring speed of 180r / min to obtain a mixed solution.

[0072] S3. Filter the mixed solution prepared in S2, then add saturated saline and sodium bicarbonate to the filtrate, and perform organic phase extraction after stirring at 300 r / min for 0.9 h;

[0073] S4. The organic phase extracted in S3 was subjected to a first vacuum distillation at 110℃ for 5 h to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol was recovered, and the crude vanillyl butyl ether was subjected to a second vacuum distillation at 155℃ for 3.5 h to obtain vanillyl butyl ether.

[0074] The quality, yield, and purity of the vanillyl butyl ether prepared in Examples 1-9 above were tested, and the specific test data are shown in the table below.

[0075] Example Yield (g) Yield (%) purity(%) 1 186.06 88.6 >99 2 198.16 94.36 >99 3 202.104 96.24 >99 4 206.136 98.16 >99 5 200 95.24 >99 6 207.102 98.62 >99 7 206.54 98.35 >99 8 207.19 98.66 >99 9 207.52 98.82 >99

[0076] As can be seen from the table above, the vanillin butyl ethers prepared in Examples 1-9 all have a purity of >99%, indicating that the montmorillonite / silica gel supported phosphotungstic acid, montmorillonite / silica gel supported styrene cation exchange resin, and montmorillonite / silica gel supported ZSM-5 molecular sieve used in this invention all have good catalytic effects, thus providing stable and good purity control for vanillin butyl ether.

[0077] Regarding the yield, Example 1 is lower than Examples 2-9, with Example 1 having a yield of 88.6%, while Examples 2-9 all maintained above 94%. This is because the amount of n-butanol added in step S2 of Example 1 is small. The lower amount of n-butanol added will affect its contact efficiency with vanillin, and the etherification reaction cannot be fully completed, resulting in the lowest yield of Example 1.

[0078] Furthermore, in step S3 of Examples 1-9, montmorillonite / silica gel supported phosphotungstic acid, montmorillonite / silica gel supported styrene cation exchange resin, or montmorillonite / silica gel supported ZSM-5 molecular sieve can all be separated by filtration, and then recovered after washing and drying, with a recovery rate of 80-95%.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for synthesizing vanillyl butyl ether, characterized in that, Includes the following steps: S1. Preparation of vanillin; S2. Vanillin prepared in S1, n-butanol, and catalyst are added to a reaction vessel and stirred until homogeneous to carry out the reaction. After the reaction is completed, a mixed solution is obtained. S3. Filter the mixed solution prepared in S2, pretreat the filtrate, and then extract the organic phase from the filtrate; S4. The organic phase extracted in S3 is subjected to a first vacuum distillation to obtain crude vanillyl butyl ether and n-butanol. Then, the n-butanol is recovered and the crude vanillyl butyl ether is subjected to a second vacuum distillation to obtain vanillyl butyl ether.

2. The method for synthesizing vanillyl butyl ether according to claim 1, characterized in that, In step S1, the specific preparation method of vanillin includes the following steps: S11. Mix sodium hydroxide, desalinated water and vanillin and stir to react and form solution a; S12. Continue stirring solution a prepared in S11, and add sodium borohydride to react and form solution b; S13. Add hydrochloric acid to solution b prepared in S12 to adjust to neutral, then filter and wash to obtain vanillin.

3. The method for synthesizing vanillyl butyl ether according to claim 2, characterized in that, In step S11, the mass ratio of sodium hydroxide to the volume ratio of demineralized water is 1:10 to 1:20, and the molar ratio of vanillin to sodium hydroxide is 1:0.5 to 1:1.

5.

4. The method for synthesizing vanillyl butyl ether according to claim 2, characterized in that, In step S12, the molar ratio of sodium borohydride to vanillin is 0.5:1 to 1.2:1, the stirring speed is 50 to 500 r / min, the reaction temperature is 20 to 40℃, and the reaction time is 1 to 3 h.

5. The method for synthesizing vanillyl butyl ether according to claim 2, characterized in that, In step S13, the washing process uses demineralized water.

6. The method for synthesizing vanillyl butyl ether according to claim 1, characterized in that, In step S2, the mass ratio of vanillin to n-butanol is 1:2 to 1:10, and the mass ratio of vanillin to catalyst is 1:1.23 to 1:1.

30. The catalyst is one of montmorillonite / silica gel supported phosphotungstic acid, montmorillonite / silica gel supported styrene cation exchange resin, and montmorillonite / silica gel supported ZSM-5 molecular sieve. Specifically, the mass ratio of montmorillonite / silica gel to phosphotungstic acid is 1:0.005 to 1:0.1, the mass ratio of montmorillonite / silica gel to styrene cation exchange resin is 1:0.008 to 1:0.18, and the mass ratio of montmorillonite / silica gel to ZSM-5 molecular sieve is 1:0.008 to 1:0.

2.

7. The method for synthesizing vanillyl butyl ether according to claim 1, characterized in that, In step S2, the stirring speed is 50–350 r / min, the reaction temperature is 30–100℃, and the reaction time is 3–16 h.

8. The method for synthesizing vanillyl butyl ether according to claim 1, characterized in that, In step S3, the specific pretreatment method is as follows: add saturated saline and sodium bicarbonate to the mixed solution and stir at 50-350 r / min for 0.5-1.5 h.

9. The method for synthesizing vanillyl butyl ether according to claim 1, characterized in that, In step S4, the temperature of the first vacuum distillation is 50-110℃ and the time is 0.5-5h; the temperature of the second distillation is 120-180℃ and the time is 0.5-3.5h.

10. A vanillyl butyl ether, characterized in that, It is prepared by the synthesis method according to any one of claims 1-9.