Preparation method of allyl glycidyl ether

Abstract

The invention relates to a preparation method of allyl glycidyl ether, which comprises the following step: by taking a metal compound with reaction control phase transfer catalysis as a catalyst and hydrogen peroxide as an oxygen source, carrying out selective epoxidation on allyl ether in the presence of an additive to prepare the allyl glycidyl ether. The method has the advantages of high catalytic selectivity, low production cost, safe and non-toxic raw materials and simple operation.

Description

Technical Field

[0001] This invention belongs to the field of organic compound synthesis technology, and specifically relates to a method for preparing allyl glycidyl ether. Background Technology

[0002] Allyl glycidyl ether is a compound with both epoxy end groups and carbon-carbon double bonds, possessing a wide range of applications. It can be used as an epoxy reactive diluent, chloride stabilizer, fabric finishing agent, reactive intermediate in elastomers, epoxy resins, adhesives, coatings and fibers, glass fiber surface repair agent, scale inhibitor, unsaturated polyester drying agent, and organosilicon intermediate in electronic coatings. In China, allyl glycidyl ether is mainly used in the synthesis of the silane coupling agent KH-560.

[0003] There are three main methods for synthesizing allyl glycidyl ether. The first is the phase-transfer catalytic method, which uses allyl alcohol and epichlorohydrin as raw materials, reacting them in the presence of a phase-transfer catalyst and sodium hydroxide to generate allyl glycidyl ether. The second is the sodium alkoxide method, where allyl alcohol reacts with sodium hydroxide to prepare sodium allyl alkoxide, which then reacts with epichlorohydrin to generate the product. The third is a two-step ring-opening and ring-closing method, using allyl alcohol and propylene oxide as raw materials. In the presence of a catalyst, the epoxy undergoes ring-opening addition to give the intermediate 1-allyloxy-3-chloro-2-propanol, which then undergoes ring-closing with HCl in an alkaline solution to generate the product.

[0004] In the phase-transfer catalysis method for synthesizing allyl glycidyl ether, there is no ring-opening or ring-closing reaction stage. Sodium hydroxide is both a Lewis base catalyst and a reactant that removes HCl. Ding Bing (CN 107915695A) introduced a method and apparatus for synthesizing allyl glycidyl ether via phase transfer catalysis. Compared with the "two-step method," this method simplifies the reaction steps, enables continuous production, and improves reaction efficiency. The ring-opening and ring-closing two-step method is a commonly used method for synthesizing allyl glycidyl ether and is also an industrial production method. Xu Mengyi, Lin Dongen, et al. used boron trifluoride diethyl ether complex as a catalyst, followed by a ring-closing reaction to obtain the product, with a total yield (based on allyl alcohol) of 73%. Tang Xinhua (CN100999507A) and Zhu Xinbao (CN1927851A) used boron trifluoride diethyl ether complex and perchlorate as catalysts, respectively, to obtain the product, with yields reaching 78% and 80%, respectively. Jin Liantie (CN103333137A) used a ternary composite catalyst to obtain the product allyl glycidyl ether through ring-opening and ring-closing, with a yield of up to 91% based on epichlorohydrin.

[0005] Publicly available technologies for synthesizing allyl glycidyl ethers indicate that the phase-transfer catalytic method results in excessive epichlorohydrin production, lacks effective recovery methods, and has high production costs. The sodium alkoxide method produces excessive allyl alcohol during sodium allyl alkoxide preparation, resulting in high water content in the recovered allyl alcohol and high dehydration costs. The two-step ring-opening and ring-closing method is cumbersome, and the ring-closing reaction product contains a large amount of solid sodium chloride, requiring filtration, making the process complex. Furthermore, existing methods all use allyl alcohol as a raw material; allyl alcohol is highly toxic, requiring highly skilled operating equipment and personnel, and the waste treatment process is cumbersome and pollutes the environment. Summary of the Invention

[0006] To address the problems of highly toxic raw materials and environmental pollution caused by waste liquids in the three current synthetic routes, this invention provides a preparation method with high catalytic selectivity, low production cost, safe and non-toxic raw materials, and simple operation. After the reaction, the catalyst is solid and can be separated for reuse. The reaction liquid is separated and then distilled to obtain the target product, allyl glycidyl ether.

[0007] The technical solution adopted by this invention to solve the above-mentioned technical problems is: a method for synthesizing allyl glycidyl ether, specifically including the following steps:

[0008] (1) Add allyl ether, catalyst and additives to the reaction vessel;

[0009] (2) Hydrogen peroxide was added dropwise at 30-80℃, and the reaction was carried out for 1-10 hours to obtain the crude product;

[0010] (3) The crude product obtained in step (2) is filtered, separated, and distilled to obtain the finished product.

[0011] According to the above scheme, the molar ratio of the catalyst to allyl ether is 4000:1 to 1000:1, the molar ratio of hydrogen peroxide to allyl ether is between 4:1 and 1:4, the mass ratio of the additive to allyl ether is [missing information], and the reaction temperature is 30 to 80°C.

[0012] The catalyst is a mixture of heteropolyacid compounds with reaction-controlled phase transfer characteristics, and its overall composition is Q. m H n PM x O y Q is a quaternary ammonium salt cation, which is one or more of hexadecyltrimethylamine salt, tetradecyltrimethylamine salt, dodecyltrimethylamine salt, octadecyltrimethylamine salt, dioctadecyldimethylamine salt, benzyl quaternary ammonium salt, and tetrabutylamine salt; M is a metal, which is one or more of molybdenum, tungsten, or vanadium; 1≤m≤7, 0≤n≤3, 1≤x≤10, 7≤y≤34.

[0013] The additives are one or more of the following: phosphoric acid, mixed phosphoric acid, diammonium hydrogen phosphate, diammonium dihydrogen phosphate, hydrogen phosphate, mixed phosphates, and orthophosphates.

[0014] In the preparation method of allyl glycidyl ether of the present invention, the reaction-controlled phase transfer catalyst is separated, recovered and recycled.

[0015] In the preparation method of allyl glycidyl ether of the present invention, the concentration of hydrogen peroxide in step (2) is 10-70%.

[0016] The present invention addresses the issue of handling excess allyl ether after the epoxidation reaction. In industrial production, this can be separated by vacuum distillation and recycled.

[0017] The main chemical reaction formulas involved in this invention are as follows:

[0018]

[0019] The epoxidation reaction conditions in this invention are mild, the epoxidation process is simple and easy to implement, the production cycle is short, the cost is low, the selectivity is high, and the whole process is green and environmentally friendly. The crude product is detected by gas chromatography, and the yield is over 90% based on hydrogen peroxide. The product obtained by distillation has a purity of over 99%. Detailed Implementation

[0020] The following examples further illustrate the present invention. The present invention includes, but is not limited to, the following examples.

[0021] Example 1: Preparation of Catalyst

[0022] Add 10.0 g of 5% phosphomolybdic acid aqueous solution to 20 mL of 30% hydrogen peroxide solution, heat to 60 °C, and stir for 1 hour to obtain a colorless and transparent solution. Add 40 mL of deionized water and 1.0 g of 85% phosphoric acid, and continue stirring for 1 hour. Weigh 5 g of hexadecyltrimethylammonium bromide and dissolve it in 100 mL of dichloroethane. Slowly add this solution dropwise to the above solution, and continue stirring for 2 hours to obtain a precipitate. Wash the precipitate with deionized water until the pH of the filtrate is 3.5. The dried solid is the catalyst. XRF characterization of the catalyst reveals a composition of Q. 2.8 H 2.4 PM 3.2 O 18.6 (M represents molybdenum).

[0023] Example 2

[0024] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O18.6 1 g of phosphoric acid and 0.05 g of phosphate were added dropwise at 45°C with 10 g of 30% hydrogen peroxide. The mixture was stirred at 45°C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that the yield of allyl glycidyl ether to hydrogen peroxide was 91%, with a selectivity of 92%. Titration of the aqueous phase revealed a hydrogen peroxide content of 0.2%. Distillation of the crude product yielded allyl glycidyl ether with a purity of 99.56%.

[0025] Example 3

[0026] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.6 1 g of phosphoric acid and 0.05 g of phosphate were added dropwise to 20 g of 30% hydrogen peroxide at 45 °C. The mixture was stirred at 45 °C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that the yield of allyl glycidyl ether to hydrogen peroxide was 83%, with a selectivity of 82%. Titration of the aqueous phase revealed a hydrogen peroxide content of 0.5%. Distillation of the crude product yielded allyl glycidyl ether with a purity of 99.21%.

[0027] Example 4

[0028] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.6 1.8 g of phosphoric acid and 0.05 g of hydrogen peroxide (30% by mass) were added dropwise at 45 °C. The mixture was stirred at 45 °C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that the yield of allyl glycidyl ether to hydrogen peroxide was 92.5%, with a selectivity of 92%. Titration of the aqueous phase revealed a hydrogen peroxide content of 0.2%. Distillation of the crude product yielded allyl glycidyl ether with a purity of 99.63%.

[0029] Example 5

[0030] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.61 g of phosphoric acid and 0.05 g of phosphate were added dropwise at 45 °C with 10 g of 30% hydrogen peroxide. The mixture was stirred at 65 °C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that allyl glycidyl ether had a 90% yield and 90% selectivity for hydrogen peroxide. Titration of the aqueous phase revealed a hydrogen peroxide content of 0.2%. Distillation of the crude product yielded allyl glycidyl ether with a purity of 99.34%.

[0031] Example 6

[0032] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.6 1 g of phosphoric acid and 0.05 g of phosphate were added dropwise at 45°C with 6 g of 50% hydrogen peroxide. The mixture was stirred at 45°C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that the yield of allyl glycidyl ether to hydrogen peroxide was 92%, with a selectivity of 91%. Titration of the aqueous phase revealed a hydrogen peroxide content of 0.2%. Distillation of the crude product yielded allyl glycidyl ether with a purity of 99.69%.

[0033] Example 7

[0034] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.6 1 g of phosphoric acid and 0.05 g of phosphate were added dropwise at 45°C with 10 g of 30% hydrogen peroxide. The mixture was stirred at 45°C for 6 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that the yield of allyl glycidyl ether to hydrogen peroxide was 93%, with a selectivity of 93%. Titration of the aqueous phase revealed a hydrogen peroxide content of 0.2%. Distillation of the crude product yielded allyl glycidyl ether with a purity of 99.72%.

[0035] Example 8

[0036] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.61g of phosphoric acid and 0.05g of hydrogen peroxide (30% by mass) were added dropwise at 45℃. The mixture was stirred at 45℃ for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that allyl glycidyl ether had a hydrogen peroxide yield of 91% and a selectivity of 92%. The hydrogen peroxide content in the aqueous phase was 0.2%. Distillation of the crude product yielded allyl glycidyl ether with a purity of 99.56%. The catalyst was recovered by centrifugation and a recycling experiment was conducted. The results are shown in the table below.

[0037]

[0038] Comparative Example 1

[0039] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.6 1 g of phosphoric acid and 0.05 g of hydrogen peroxide (5% by mass) were added dropwise at 45 °C. The mixture was stirred at 45 °C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that allyl glycidyl ether had a yield of 25% for hydrogen peroxide and a selectivity of 34%.

[0040] Comparative Example 2

[0041] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.6 1 g of phosphoric acid and 0.05 g of hydrogen peroxide (30% by mass) were added dropwise at 45 °C. The mixture was stirred at 45 °C for 0.5 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 65%. Gas chromatography analysis of the reaction oil phase showed that allyl glycidyl ether had a yield of 42% for hydrogen peroxide and a selectivity of 54%.

[0042] Comparative Example 3

[0043] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Example 1. 2.8 H 2.4 PM 3.2 O 18.6 1 g of phosphoric acid and 0.05 g of hydrogen peroxide (30% by mass) were added dropwise at 45 °C. The mixture was stirred at 100 °C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that allyl glycidyl ether had a yield of 45% and a selectivity of 48% for hydrogen peroxide.

[0044] Comparative Example 4

[0045] Add 5.0 g of 10% phosphotungstic acid aqueous solution to 20 mL of 30% hydrogen peroxide solution, heat to 60 °C, and stir for 1 hour to obtain a colorless and transparent solution. Add 40 mL of deionized water and 1.0 g of 85% phosphoric acid, and continue stirring for 1 hour. Weigh 5 g of hexadecyltrimethylammonium bromide and dissolve it in 100 mL of dichloroethane. Slowly add this solution dropwise to the above solution, and continue stirring for 2 hours to obtain a precipitate. Wash the precipitate with deionized water until the pH of the filtrate is 3.5. The dried solid is the catalyst. XRF characterization of the catalyst reveals a composition of Q. 2.8 H 2.4 PM 4.8 O 18.6 (M is W).

[0046] 31.41 g of allyl ether was added to a three-necked flask, along with catalyst Q prepared in Comparative Example 4. 2.8 H 2.4 PM 4.8 O 18.6 1 g of phosphoric acid and 0.05 g of 30% hydrogen peroxide were added dropwise at 45°C. The mixture was stirred at 45°C for 2 hours, cooled, and then centrifuged to separate the solid catalyst. The catalyst recovery rate was 98%. Gas chromatography analysis of the reaction oil phase showed that allyl glycidyl ether had a yield of 45% and a selectivity of 49% for hydrogen peroxide.

[0047] Comparative Example 5

[0048] 31.41 g of allyl ether and 0.05 g of phosphoric acid were added to a three-necked flask. 10 g of 30% hydrogen peroxide was added dropwise at 45 °C. The mixture was stirred at 45 °C for 2 hours. The reaction oil phase was analyzed by gas chromatography. The yield of allyl glycidyl ether to hydrogen peroxide was 0%, and the selectivity was 0%.

[0049] The above examples demonstrate that, according to the reaction route and conditions provided by this invention, diallyl ether can be directly catalyzed to prepare allyl glycidyl ether with high efficiency and selectivity. The catalyst can be separated and recycled after the reaction is completed, which is an environmentally friendly technical route.

Claims

1. A method for preparing allyl glycidyl ether, characterized in that: Using a metal compound with reaction-controlled phase transfer catalysis as a catalyst and hydrogen peroxide as an oxygen source, allyl ether is selectively epoxidized in the presence of additives to prepare allyl glycidyl ether.

2. The preparation method according to claim 1, characterized in that, The specific steps are as follows: (1) Add allyl ether, catalyst and additives to the reaction vessel; (2) Hydrogen peroxide is added dropwise at a certain temperature, and the reaction is carried out for a period of time to obtain the crude product; (3) The crude product obtained in step (2) is filtered, separated, and distilled to obtain the finished product.

3. The preparation method according to claim 1 or 2, characterized in that: The catalyst is a mixture of heteropolyacid compounds with reaction-controlled phase transfer characteristics, with a composition of Q. m H n PM x O y Q is a quaternary ammonium salt cation, which is one or more of hexadecyltrimethylamine salt, tetradecyltrimethylamine salt, dodecyltrimethylamine salt, octadecyltrimethylamine salt, dioctadecyldimethylamine salt, benzyl quaternary ammonium salt and tetrabutylamine salt; M is metallic molybdenum; 1≤m≤7 (preferably 1≤m≤5), 0≤n≤3 (preferably 0.5≤n≤2.5), 1≤x≤10 (preferably 2≤x≤8), 7≤y≤34 (preferably 9≤y≤30).

4. The preparation method according to claim 1, characterized in that: The additive is one or more of the following: phosphoric acid, diammonium hydrogen phosphate, ammonium dihydrogen phosphate, hydrogen ammonium phosphate, mixed phosphates, and orthophosphates.

5. The preparation method according to claim 1, characterized in that: The hydrogen peroxide concentration in step (2) is 10% to 70% (preferably 20% to 60%, more preferably 30% to 50%).

6. The preparation method according to claim 1, characterized in that: The reaction-controlled phase transfer catalyst is separated, recovered, and recycled.

7. The preparation method according to any one of claims 1-6, characterized in that: The molar ratio of allyl ether to catalyst is 4000:1 to 1000:1 (preferably 3000:1 to 1000:1, more preferably 2500:1 to 1500:1), the molar ratio of hydrogen peroxide to allyl ether is 4:1 to 1:4 (preferably 1:1 to 1:4, more preferably 1:2 to 1:4), the mass ratio of additive to allyl ether is 1:500 to 1:2000 (preferably 1:600 ​​to 1:1500, more preferably 1:600 ​​to 1:1200), the reaction temperature is 30 to 80°C (preferably 40 to 70°C, more preferably 50 to 60°C), and the reaction time is 2 to 6 hours (preferably 2.5 to 5 hours, more preferably 2.5 to 4.5 hours).

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