Catalyst for epoxidation of a bicyclic diene compound, process for its preparation and use

Abstract

The application provides a catalyst for epoxidation of bicyclic diene compounds and a preparation method and application thereof. The catalyst comprises a peroxypolytungstate quaternary ammonium salt selected from one or more of A3[PW4O 24 ], A2[SeW2O 14 ], A3[AsW4O 24 ], A3[(OH)SiW3O 18 ], and A2[SW2O 14 ], wherein A is an organic quaternary ammonium salt cation with 8-24 carbon atoms. The catalyst can significantly improve the reaction rate, conversion rate and selectivity of epoxidation of bicyclic diene compounds.

Description

Technical Field

[0001] This application relates to the field of catalytic chemistry technology, specifically to a catalyst for the epoxidation of bicyclic diene compounds, its preparation method, and its application. Background Technology

[0002] Aliphatic biepoxides are a type of epoxy resin developed by Union Carbide Corporation in the United States. Compared with bisphenol A type epoxy resins, they have the characteristics of good thermal stability, high weather resistance, and excellent electrical insulation performance. Therefore, aliphatic biepoxides are widely used in coatings, packaging, electronics, automobiles and other fields, and there is a large global demand for them.

[0003] Aliphatic bicyclic epoxy compounds prepared by epoxidation of dicyclic dienes have good properties. Currently, the industrial method for preparing aliphatic bicyclic epoxy compounds by epoxidation of dicyclic dienes is mostly carried out, but it has disadvantages such as low conversion rate and poor selectivity.

[0004] Therefore, it is necessary to improve the conversion rate and selectivity of epoxidation of bicyclic diene compounds to prepare aliphatic bicyclic oxide compounds. Summary of the Invention

[0005] This application provides a catalyst for the epoxidation of dicyclic diene compounds, its preparation method, and its application, aiming to improve the reaction rate, conversion rate, and selectivity of the epoxidation of dicyclic diene compounds to produce aliphatic diepoxide compounds.

[0006] In a first aspect, this application provides a catalyst for the epoxidation of bicyclic diene compounds, the catalyst comprising a peroxypolytungstate quaternary ammonium salt selected from A3[PW4O] 24 ]、A2[SeW2O 14 ]、A3[AsW4O 24 ]、A3[(OH)SiW3O 18 ] and A2[SW2O 14 One or more of the following:

[0007] Wherein, A is an organic quaternary ammonium salt cation with 8 to 24 carbon atoms.

[0008] According to this application, a catalyst comprising peroxypolytungstate quaternary ammonium salt is provided, which can be used for the epoxidation of dicyclic dienes to produce aliphatic diepoxides. It has high catalytic activity and can obtain aliphatic diepoxides with high specificity and selectivity. It can significantly improve the reaction rate, conversion rate and selectivity of the epoxidation of dicyclic dienes to produce aliphatic diepoxides, with a conversion rate of over 95% and a selectivity of over 99.8%. In addition, the catalyst is easy to recover and can be reused, thereby saving production costs.

[0009] In some embodiments of the present application, A is an organic quaternary ammonium salt cation with carbon number of 16-21.

[0010] In some embodiments of the present application, A is [C 18 H 37 N(CH3)3] + or [C 16 H 36 N] +

[0011] In some embodiments of the present application, the peroxopolytungstate quaternary ammonium salt is selected from one or more of [C 18 H 37 N(CH3)3]3[PW4O 24 ], [C 18 H 37 N(CH3)3]2[SeW2O 14 ], [C 18 H 37 N(CH3)3]3[AsW4O 24 ], [C 18 H 37 N(CH3)3]3[(OH)SiW3O 18 ], and [C 16 H 36 N]2[SW2O 14 ].

[0012] In some embodiments of the present application, the catalyst further comprises a carrier, and the peroxopolytungstate quaternary ammonium salt is loaded on the carrier.

[0013] Optionally, the carrier is selected from one or more of metal oxides, diatomite, zeolite, activated carbon, and silica gel.

[0014] In a second aspect, the present application provides a use of the catalyst according to any one of the embodiments of the first aspect in the preparation of aliphatic bis-epoxides.

[0015] According to the present application, the catalyst according to any one of the embodiments of the first aspect is used in the preparation of aliphatic bis-epoxides, which has a high reaction rate, conversion rate and selectivity, and recycling of the catalyst can reduce the production cost.

[0016] In a third aspect, the present application provides a method for preparing 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylformate, comprising the following steps:

[0017] ​In the presence of a catalytic amount of the catalyst according to any one of the embodiments of the first aspect, 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and an oxidizing agent are subjected to epoxidation in an organic solvent to obtain 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate.

[0018] According to the present application, the catalyst according to any one of the embodiments of the first aspect is used to catalyze the epoxidation of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to produce 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate. It can be understood that the method for preparing 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate has the beneficial effects of the first aspect, i.e., has a high reaction rate, conversion rate and selectivity, and recycling of the catalyst can reduce production costs.

[0019] In some embodiments of the present application, the method specifically comprises the following steps:

[0020] S1: dissolving and dispersing 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and the catalyst according to any one of the embodiments of the first aspect in an organic solvent to obtain a mixture;

[0021] S2: adding an oxidizing agent dropwise to the mixture at a preset reaction temperature to cause the 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to undergo epoxidation to obtain 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate.

[0022] In some embodiments of the present application, the mass ratio of the 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the catalyst is 1:0.01-0.5.

[0023] In some embodiments of the present application, the molar ratio of the 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the oxidizing agent is 1:1-5.

[0024] In some embodiments of the present application, the organic solvent is selected from one or more of ethyl acetate, dichloroethane, tert-butanol, 1,4-dioxane, acetonitrile; and / or the oxidizing agent is hydrogen peroxide and / or peracetic acid.

[0025] In some embodiments of the present application, the step S1 further comprises dispersing a water removal agent in the organic solvent.

[0026] In some embodiments of the present application, in the step S2, the preset reaction temperature is 20-70°C. DETAILED DESCRIPTION

[0027] The embodiments or implementations in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments.

[0028] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the implementation or example are included in at least one implementation or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily mean the same implementation or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more implementations or examples as appropriate.

[0029] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited. In the description of the present application, "room temperature" has the meaning known in the art, generally refers to a temperature of "15℃ to 35℃", unless otherwise specifically limited.

[0030] As described in the background section above, the current industry is mostly used to use bicyclic diene compound as raw material, through organic peracid method to synthesize aliphatic diepoxide compound, but there are low conversion rate and poor selectivity and other shortcomings.

[0031] Based on this, using catalyst to catalyze the epoxidation reaction of bicyclic diene compound is considered to be an effective way to improve the reaction rate, conversion rate and selectivity. Therefore, the inventors found through a large number of experiments that using a catalyst containing a specific type of peroxopolytungstate quaternary ammonium salt can effectively improve the reaction rate, conversion rate and selectivity of the epoxidation of bicyclic diene compound to produce aliphatic diepoxide compound.

[0032] It should be noted that, unless otherwise specified, the conversion rate described in the context of the present application refers to the conversion rate of bicyclic diene compound, which can be calculated by the following formula: conversion rate = m / (n*M), wherein m represents the mass of the actual product, n is the amount of substance of bicyclic diene compound in the raw material, and M is the molar mass of bicyclic diene compound; the highest conversion rate is 100%.

[0033] Unless otherwise specified, the selectivity described in this application refers to the selectivity of the epoxidation reaction of bicyclic diene compounds, which can be obtained by calculating the mass fraction of the target aliphatic bicyclic epoxy compound in the actual product, with a maximum selectivity of 100%. Since other byproducts may be generated during the epoxidation of bicyclic diene compounds to produce the target aliphatic bicyclic epoxy compound (such as incomplete epoxidation or monoepoxides formed by ring opening of epoxides), the actual product generally contains a certain amount of byproducts. Qualitative and quantitative analysis of the actual product can be performed using gas chromatography and gas chromatography-mass spectrometry (GC-MS) to calculate the mass fraction of the target aliphatic bicyclic epoxy compound in the actual product, which is the selectivity of the epoxidation reaction of the bicyclic diene compound.

[0034] The catalysts for the epoxidation of bicyclic diene compounds provided in this application and their applications are described in detail below.

[0035] In a first aspect, this application provides a catalyst for the epoxidation of bicyclic diene compounds, the catalyst comprising a peroxypolytungstate quaternary ammonium salt selected from A3[PW4O] 24 ]、A2[SeW2O 14 ]、A3[AsW4O 24 ]、A3[(OH)SiW3O 18 ] and A2[SW2O 14 One or more of the following:

[0036] Wherein, A is an organic quaternary ammonium salt cation with 8 to 24 carbon atoms.

[0037] According to this application, the inventors discovered through extensive experiments that certain types of peroxypolytungstate quaternary ammonium salts exhibit high catalytic activity for the epoxidation reaction of bicyclic diene compounds. In peroxypolytungstate quaternary ammonium salts, both the type of peroxypolytungstate anion and the type of organic quaternary ammonium salt cation have a certain influence on the catalytic activity. Specifically, the inventors found that the peroxypolytungstate anion is [PW4O]... 24 ] 3- [SeW2O] 14 ] 2- [AsW4O] 24 ] 3- [(OH)SiW3O] 18 ] 3- or [SW2O] 14 ] 2-and the carbon atom number of the organic quaternary ammonium salt cation is 8-24, the peroxopolytungstate quaternary ammonium salt has extremely high catalytic activity for the epoxidation reaction of the bicyclic diene compound. For example, the carbon atom number of the organic quaternary ammonium salt can be 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24.

[0038] Therefore, when the catalyst containing the above-mentioned peroxopolytungstate quaternary ammonium salt is used for the production of aliphatic diepoxide compounds by the epoxidation of a bicyclic diene compound, the following beneficial effects can be achieved due to the high catalytic activity:

[0039] (1) The epoxidation reaction rate can be effectively improved, and the production efficiency can be improved. In addition, a lower reaction temperature can be used, which improves safety and saves production costs.

[0040] (2) The epoxidation of a bicyclic diene compound can be performed using an oxidant with relatively stable properties and slightly weak oxidizing properties. For example, low-concentration hydrogen peroxide can be used as an oxidant, which has stable properties and is environmentally friendly. The use of traditional organic peroxides (such as organic peroxy acids) can be avoided, which can effectively overcome the problems of explosion and the generation of a large amount of acidic waste liquid, which can cause corrosion of the reaction equipment. In addition, under acidic conditions, the target product aliphatic diepoxide compound is prone to acid ring opening to generate aliphatic monoepoxide and other by-products, which are difficult to separate from the target product, resulting in a decrease in the selectivity of the reaction. In addition, in order to avoid the influence of the acidic waste liquid, a large amount of inorganic compound needs to be added to the system, which will generate a large amount of salt-containing wastewater, polluting the environment and increasing the production cost. Therefore, the use of the above-mentioned catalyst can avoid the use of organic peroxides, thereby effectively overcoming the above-mentioned problems.

[0041] (3) The conversion rate and selectivity of the reaction system can be effectively improved. It has been found through experiments that under appropriate reaction conditions, the conversion rate and selectivity of the production of 2, aliphatic diepoxide compounds by the epoxidation of a bicyclic diene compound can reach more than 95% and more than 99.8%, respectively, which can effectively reduce the production cost.

[0042] (4) The above-mentioned catalyst is easy to recover in the reaction system and has good catalytic stability, and can be recycled multiple times, thereby further reducing the production cost.

[0043] In some embodiments of the present application, A is an organic quaternary ammonium salt cation with a carbon atom number of 16-21.

[0044] In some of the above embodiments, as mentioned above, the number of carbon atoms of the organic quaternary ammonium cation of the peroxopolytungstate quaternary ammonium salt has a certain influence on its catalytic activity. Through a large number of experiments, it is found that under the same conditions, when the number of carbon atoms of the organic quaternary ammonium cation is 16-21, the catalytic activity of the peroxopolytungstate quaternary ammonium salt is better.

[0045] In some embodiments of the present application, A is [C 18 H 37 N(CH3)3] + or [C 16 H 36 N] + .

[0046] In some of the above embodiments, the inventors further found through a large number of experiments that the catalytic activity of the peroxopolytungstate quaternary ammonium salt is not only related to the number of C atoms of the organic quaternary ammonium cation, but also related to the specific structure of the organic quaternary ammonium cation. Under the same conditions, when the organic quaternary ammonium cation is [C 18 H 37 N(CH3)3] + or [C 16 H 36 N] + , the catalytic activity of the peroxopolytungstate quaternary ammonium salt is better.

[0047] In some embodiments of the present application, the peroxopolytungstate quaternary ammonium salt is selected from one or more of [C 18 H 37 N(CH3)3]3[PW4O 24 ], [C 18 H 37 N(CH3)3]2[SeW2O 14 ], [C 18 H 37 N(CH3)3]3[AsW4O 24 ], [C 18 H 37 N(CH3)3]3[(OH)SiW3O 18 ], and [C 16 H 36 N]2[SW2O 14 ].

[0048] In some of the above embodiments, several peroxopolytungstate quaternary ammonium salts with high catalytic activity are specifically listed. When a catalyst containing the above peroxopolytungstate quaternary ammonium salt is used for the epoxidation of bicyclic olefin compounds to produce 2,3-epoxypinane, it has high reaction rate, conversion rate and selectivity.

[0049] In some embodiments of the present application, the catalyst further comprises a carrier, and the peroxopolytungstate quaternary ammonium salt is loaded on the carrier.

[0050] Optionally, the carrier is selected from one or more of diatomite, zeolite, activated carbon and silica gel.

[0051] In some embodiments described above, the catalyst can further comprise a carrier, and the peroxopolytungstate quaternary ammonium salt is loaded on the carrier. It can be understood that the peroxopolytungstate quaternary ammonium salt can be directly used as a catalyst in the reaction system, and further, it can be loaded on the carrier and used as a catalyst in the reaction system. The carrier can serve as a skeleton of the peroxopolytungstate quaternary ammonium salt, and can stabilize the dispersion of the peroxopolytungstate quaternary ammonium salt, thereby increasing the catalytic activity and catalytic stability of the peroxopolytungstate quaternary ammonium salt. In addition, loading the peroxopolytungstate quaternary ammonium salt on the carrier can facilitate the recycling and reuse of the peroxopolytungstate quaternary ammonium salt, thereby reducing the production cost.

[0052] Further, the carrier can be selected from one or more of diatomite, zeolite, activated carbon and silica gel. It can be understood that the carrier can stably load the peroxopolytungstate quaternary ammonium salt, and does not react with the raw materials and products in the reaction system. Those skilled in the art can select the carrier according to the actual situation.

[0053] In some embodiments of the present application, A3[PW4O 24 ] can be prepared by the following method:

[0054] Concentrated hydrochloric acid is added to sodium tungstate, and then hydrogen peroxide is added to react, and then phosphoric acid is added to obtain a mixed solution. A soluble quaternary ammonium salt containing A is added to the mixed solution to obtain A3[PW4O 24 ]. The A3[PW4O 24 ] obtained by the above method has a high yield.

[0055] In some embodiments of the present application, A2[SeW2O 14 ] can be prepared by the following method:

[0056] Hydrogen peroxide is added to tungstic acid to react, and then selenic acid is added to obtain a mixed solution. A soluble quaternary ammonium salt containing A is added to the mixed solution to obtain A2[SeW2O 14 ]. The A2[SeW2O 14 ] obtained by the above method has a high yield.

[0057] In some embodiments of the present application, A3[AsW4O 24 ] can be prepared by the following method:

[0058] Concentrated hydrochloric acid is added to sodium tungstate, and then hydrogen peroxide is added to react, and then hydrogen sodium arsenate is added to obtain a mixed solution. A soluble quaternary ammonium salt containing A is added to the mixed solution to obtain A3[AsW4O 24A3[AsW4O 24 ] has a high yield.

[0059] In some embodiments of the present application, A3[(OH)SiW3O 18 ] can be prepared by the following method:

[0060] A3[(OH)SiW3O 10 O 36 ] is added to the mixed solution to obtain A3[(OH)SiW3O 18 ] has a high yield. 18

[0061] In some embodiments of the present application, A2[SW2O 14 ] can be prepared by the following method:

[0062] A2[SW2O 14 ] is added to the mixed solution to obtain A2[SW2O 14 ] has a high yield.

[0063] It can be understood that A3[PW4O 24 ], A2[SeW2O 14 ], A3[AsW4O 24 ], A3[(OH)SiW3O 18 ] and A2[SW2O 14 ] include but are not limited to the above-mentioned preparation methods.

[0064] In some embodiments of the present application, the bicyclic diene compound is 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester or dicyclopentadiene.

[0065] In a second aspect, the present application provides a use of the catalyst according to any one of the first aspect in the preparation of aliphatic bis-epoxide compounds.

[0066] According to the present application, the catalyst according to any one of the first aspect is used to prepare aliphatic bis-epoxide compounds, which has a high reaction rate, conversion rate and selectivity, and recycling the catalyst can reduce the production cost.

[0067] In some embodiments of the present application, the catalyst according to any one of the first aspect can be used to catalyze 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to prepare 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl carboxylate.​

[0068] In some embodiments of the present application, the catalyst of any one of the first aspect can be used to catalyze the preparation of dicyclopentadiene dioxide.

[0069] In the second aspect, the present application provides a method for preparing 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylformate, comprising the following steps:

[0070] In the presence of a catalytic amount of the catalyst of any one of the first aspect, 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and an oxidant are subjected to an epoxidation reaction in an organic solvent to obtain 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylformate.

[0071] According to the present application, the catalyst of any one of the first aspect is used to catalyze the epoxidation of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to produce 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylformate. It can be understood that the method for preparing 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylformate has the beneficial effects of the first aspect, i.e., has a high reaction rate, conversion rate and selectivity, and recycling the catalyst can reduce production costs.

[0072] In some embodiments of the present application, the method specifically comprises the following steps:

[0073] S1: dissolving and dispersing 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and the catalyst of any one of the first aspect in an organic solvent to obtain a mixture;

[0074] S2: adding an oxidant dropwise to the mixture at a preset reaction temperature to make 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester undergo an epoxidation reaction to obtain 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylformate.

[0075] In some embodiments described above, the steps for preparing 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylformate are specifically limited. In step S1, 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and the catalyst of any one of the first aspect are dissolved and dispersed in an organic solvent, and the oxidant is not directly mixed. In step S2, the epoxidation reaction of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester is carried out by adding the oxidant dropwise. The advantage of this method is that it can avoid the accumulation of a large amount of oxidant in the reaction system, thereby avoiding potential safety hazards. The dropwise addition of the oxidant can also improve the conversion rate and selectivity of the reaction and save production costs.

[0076] It is worth mentioning that the catalyst according to any one of the embodiments of the first aspect has high catalytic activity, so that the reaction system has a fast reaction rate even though the oxidant is added dropwise, which is a beneficial effect brought by the catalyst.

[0077] In some embodiments of the present application, the mass ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the catalyst is 1:0.01-0.5. For example, the mass ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the catalyst can be 1:0.01, 1:0.02, 1:0.05, 1:0.1, 1:0.15, 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, 1:0.5 or a range formed by any of the above values.

[0078] In some embodiments, the mass ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the catalyst is specifically limited, because the catalyst has high catalytic activity, a small amount of catalyst can effectively improve the reaction rate, conversion rate and selectivity of the reaction system, and too high catalyst content will increase production cost, so the mass ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the catalyst can be controlled in the range of 1:0.01-0.5.

[0079] In some embodiments of the present application, the molar ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the oxidant is 1:1-5. For example, the molar ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the oxidant is 1:1, 1:1.5, 1:2, 1:2.5, 1:3, 1:3.5, 1:4, 1:4.5, 1:5 or a range formed by any of the above values.

[0080] In some embodiments, the molar ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the oxidant is specifically limited, in order to improve the conversion rate of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester, the oxidant in the reaction system can be appropriately excessive, but if the content of the oxidant is too high, the by-products of the reaction can increase, and the excessive oxidant can also cause certain safety hazards, so the molar ratio of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester to the oxidant can be controlled in the range of 1:1-5.

[0081] In some embodiments of the present application, the organic solvent is selected from one or more of ethyl acetate, dichloroethane, tert-butanol, 1,4-dioxane, acetonitrile; and / or the oxidant is hydrogen peroxide and / or peracetic acid.

[0082] In some of the above embodiments, several commonly used organic solvents are specifically listed, and the epoxidation reaction of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester is carried out in an organic solvent, which can be understood as being miscible with 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and not reacting with the components in the reaction system. Those skilled in the art can select according to actual needs. As an example, in some embodiments, 1,4-dioxane is used as the organic solvent.

[0083] The types of oxidizing agents are also specifically listed, and hydrogen peroxide and peracetic acid are commonly used oxidizing agents in the epoxidation reaction of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester. Due to the good reactivity of the above-mentioned catalyst, hydrogen peroxide with weak oxidizing property can be used as the oxidizing agent. In some embodiments, the oxidizing agent is hydrogen peroxide with a mass concentration of 15% to 35%. As an example, hydrogen peroxide with a mass concentration of 27.5% is used as the oxidizing agent.

[0084] In some embodiments of the present application, the step S1 further comprises dispersing the water removal agent in the organic solvent.

[0085] In some of the above embodiments, a water removal agent can also be included in the reaction system. Since 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate both contain ester groups, they will undergo hydrolysis. Therefore, the water removal agent can combine with the water in the hydrogen peroxide and the water generated by the reduction of hydrogen peroxide, thereby reducing the hydrolysis of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester and 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate, and thus the conversion rate and selectivity of the method can be further improved.

[0086] In some embodiments, the water removal agent can include but is not limited to acetic anhydride and anhydrous sodium sulfate. It can be understood that those skilled in the art can also select water removal agents known in the art according to the above reaction system.

[0087] In some embodiments of the present application, the preset reaction temperature is 20-70°C. For example, the preset reaction temperature can be 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C or a range consisting of any of the above values.

[0088] In some of the above embodiments, the reaction temperature of the epoxidation reaction of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester is specifically limited. It can be understood that too high or too low temperature will affect the reaction time, conversion rate and selectivity. The inventors have found through a large number of experiments that under the condition of using the above-mentioned catalyst, the conversion rate and selectivity are higher when the preset reaction temperature is 20-70°C. As an example, the preset reaction temperature is 60°C.

[0089] In some embodiments of the present application, the time for dropping the oxidizing agent is 1-5 h.

[0090] In some embodiments described above, the time for dropping the oxidizing agent is specified. It can be understood that the dropping time of the oxidizing agent has a certain relationship with the preset reaction temperature. The higher the preset reaction temperature, the shorter the dropping time of the oxidizing agent should be. The lower the preset reaction temperature, the longer the dropping time of the oxidizing agent should be. It is found by experiments that when the preset reaction temperature is 20-70°C, the dropping time of the oxidizing agent can be controlled within 1-5 h. As an example, the dropping time of the oxidizing agent is 3 h.

[0091] In some embodiments of the present application, step S2 further comprises, after the epoxidation reaction of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester, cooling to room temperature, collecting the organic phase by liquid separation, extracting the water phase with ethyl acetate, recovering the catalyst by filtration, collecting the ethyl acetate phase by liquid separation again, mixing the organic phase and the ethyl acetate phase, and rotary evaporation to obtain 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexyl carboxylate.

[0092] Embodiments

[0093] Hereinafter, the embodiments of the present application are described. The embodiments described below are exemplary and are only used to explain the present application and cannot be understood as a limitation of the present application. If the specific technology or condition is not specified in the embodiments, it is carried out according to the technology or condition described in the literature in the art or according to the product instruction. If the reagent or instrument used is not specified by the manufacturer, it is a conventional product that can be obtained by market purchase.

[0094] Embodiment 1

[0095] [C 18 H 37 N(CH3)3]3[PW4O 24 ] Preparation:

[0096] A 2500 mL flask with stirring, thermometer and condenser was charged with Na2WO4·2H2O 66 g (0.2 mol) and dissolved with 400 mL of deionized water. After the solution was clear, concentrated HCl 40 g (200 mmol) was added, and a light yellow precipitate was immediately generated. Then 30% H2O2 170 g was added to generate a peroxopolytungstate solution. After cooling to room temperature, 85% phosphoric acid 5.76 g (50 mmol) was added. After stirring at room temperature for 1 h, a solution containing 52.2 g of octadecyltrimethylammonium chloride (150 mmol) in 200 mL of tert-butyl alcohol was added. The solution was stirred at room temperature for 30 min, and then the white precipitate was collected by filtration and washed with excess deionized water and diethyl ether. The precipitate was dried by suction. The crude product was washed with excess deionized water and anhydrous ethanol, and dried in vacuum overnight to obtain [C18 H 37 N(CH3)3]3[PW4O 24 100.5g, yield 96.3%.

[0097] Example 2

[0098] Preparation of 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate:

[0099] Take a clean 2500mL beaker and weigh out [C 18 H 37 N(CH3)3]3[PW4O 24 6.26 g (3 mmol) and 4 g (28 mmol) of disodium hydrogen phosphate were placed in a beaker. 500 mL of solvent 1,4-dioxane and 330 g (1.5 mol) of 3-cyclohexenecarboxylic acid-3'-cyclohexene methyl ester were added to the beaker. The system was stirred at 60 °C for 15 min. Then, 185 g of 27.5% hydrogen peroxide (1.5 mol) was added dropwise to the solution, and the reaction was allowed to proceed for 3 h. After the reaction was complete, the system was cooled to room temperature, and the organic phase was collected by liquid-liquid extraction. The aqueous phase was extracted with ethyl acetate, and the catalyst was collected by filtration. The ethyl acetate phase was collected again by liquid-liquid extraction. The organic and ethyl acetate phases were mixed and rotary evaporated to obtain 334 g of product, with a conversion rate of 95.1%.

[0100] Example 3

[0101] [C 18 H 37 N(CH3)3]2[SeW2O 14 Preparation of ]:

[0102] Add 50.0 g (0.2 mol) H₂WO₄ and 700 mL of 27.5% H₂O₂ to a 2500 mL three-necked flask. Stir in a 60 °C water bath until a colorless and clear solution is obtained. Filter while hot, cool to room temperature, and then add 4 times the volume of 80% H₂SeO₄ (4.2 mL, 56 mmol). After stirring at room temperature for 1 h, add 200 mL of tert-butanol solution containing 69.6 g octadecyltrimethylammonium chloride (200 mmol). Stir the solution at room temperature for 30 min, filter to collect the white precipitate, and then wash with excess deionized water and diethyl ether. Dry the precipitate under vacuum. Wash the crude product with excess deionized water and anhydrous ethanol, and dry under vacuum overnight to obtain [C]. 18 H 37 N(CH3)3]2[SeW2O 14 122.3g, yield 94.2%.

[0103] Example 4

[0104] Preparation of 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl carbonate:

[0105] A clean 2500 mL flask was taken and [C 18 H 37 N(CH3)3]2[SeW2O 14 ]3.98 g (3 mmol), 4 g (28 mmol) of disodium hydrogen phosphate was taken in the flask, 500 mL of solvent 1,4-dioxane and 238 mL (1.5 mol) of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester was added to the flask, the system was stirred at 60 °C for 15 min, then 185 g of 27.5% hydrogen peroxide (1.5 mol) was added drop wise to the solution, the reaction was carried out for 3 h. After completion of the reaction, the system was cooled to room temperature, the organic phase was collected by liquid-liquid separation, the aqueous phase was extracted with ethyl acetate, the catalyst was collected by filtration, the ethyl acetate phase was again collected by liquid-liquid separation, the organic phase and ethyl acetate phase were mixed and distilled to get the product 223 g, the conversion was 97.4%.

[0106] Example 5

[0107] [C 18 H 37 N(CH3)3]3[AsW4O 24 ] was prepared:

[0108] A 2500 mL flask was taken, Na2WO4.2H2O 66 g (0.2 mol) was taken in the flask, it was dissolved in 400 mL of deionized water, after the solution was clear, concentrated HC1 40 g (200 mmol) was added to it, immediately a light yellow precipitate was formed, then 30% H2O2 170 g was added to form a peroxo polytungstate solution, it was cooled to room temperature, then 4 times Na2H[AsO4].7H2O aqueous solution (40 mL, 15.6 g, 50 mmol) was added, after stirring at room temperature for 1 h, a solution containing 52.2 g of octadecyl trimethyl ammonium chloride (100 mmol) in 200 mL of tert-butyl alcohol was added, the solution was stirred at room temperature for 30 min, the white precipitate was collected by filtration, then it was washed with excess deionized water and diethyl ether. The precipitate was sucked dry. The crude product was washed with excess deionized water and anhydrous ethanol, it was dried under vacuum overnight to get the catalyst [C 18 H 37 N(CH3)3]3[AsW4O 24 ] 98.6 g, yield 92.5%.

[0109] Example 6

[0110] Preparation of 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl carbonate:

[0111] A clean 2500 mL beaker was taken and [C 18 H 37 N(CH3)3]3[AsW4O 24 ]6.4 g (3 mmol), 4 g (28 mmol) of disodium hydrogen phosphate was taken in a beaker, 500 mL of solvent 1,4-dioxane and 238 ml (1.5 mol) of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester was added to the beaker, the system was stirred at 60 °C for 15 min, then 185 g of 27.5% hydrogen peroxide (1.5 mol) was added drop wise to the solution, the reaction was carried out for 3 h. After completion of the reaction, the system was cooled to room temperature, the organic phase was collected by liquid-liquid separation, the aqueous phase was extracted with ethyl acetate, the catalyst was collected by filtration, the ethyl acetate phase was again collected by liquid-liquid separation, the organic phase and ethyl acetate phase were mixed and rotary evaporated to get the product 219 g, the conversion was 95.9%.

[0112] Example 7

[0113] [C 18 H 37 N(CH3)3]3[(OH)SiW3O 18 ] was prepared as follows:

[0114] A 1000 mL flask with stirring, thermometer and condenser was charged with K8[γ-SiW 10 O 36 ]·12H2O (25 g, 8.5 mmol) dissolved in 480 mL of 30% H2O2, the solution was stirred at room temperature for 4 h. Octadecyltrimethylammonium chloride (29.6 g, 85 mmol) was dissolved in 200 mL of t-butanol, the mixture was stirred vigorously at 45 °C for 4 h. A white flocculent suspension appeared which was filtered, the white precipitate was collected by filtration and then washed with excess deionized water and diethyl ether. The precipitate was suction dried. The crude product was washed with excess deionized water and anhydrous ethanol and dried under vacuum overnight to give [C 18 H 37 N(CH3)3]3[(OH)SiW3O 18 ] 49.6 g, 96.1% yield.

[0115] Example 8

[0116] Preparation of 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate:

[0117] A clean 2500 mL beaker was taken and [C 18 H 37 N(CH3)3]3[(OH)SiW3O 185.5 g (3 mmol), 4 g (28 mmol) of disodium hydrogen phosphate were placed in a beaker, 500 mL of solvent 1,4-dioxane and 238 mL (1.5 mol) of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester were added to the beaker, the system was stirred at 60°C for 15 min, then 185 g of 27.5% hydrogen peroxide (1.5 mol) was added dropwise to the solution, the reaction was carried out for 3 h. After the reaction was completed, the system was cooled to room temperature, the organic phase was collected by liquid separation, the aqueous phase was extracted with ethyl acetate, the catalyst was collected by filtration, the ethyl acetate phase was collected by liquid separation again, and the organic phase and the ethyl acetate phase were mixed and rotary evaporated to obtain the product 215.3 g, with a conversion rate of 94.3%.

[0118] Example 9

[0119] [C 16 H 36 N]2[SW2O 14 ] was prepared as follows:

[0120] A 2500 mL three-necked flask was charged with 50.0 g (0.2 mol) of H2WO4 and 700 mL of 27.5% H2O2, and stirred to a colorless clear solution on a 60°C water bath, and then filtered hot. After cooling to room temperature, 2 mol / L aqueous H2SO4 solution (8 mL, 70 mmol) was added. After stirring at room temperature for 1 h, a solution containing tetrabutylammonium hydrogen sulfate (67.9 g, 200 mmol) in 200 mL of tert-butanol was added, and the solution was stirred at room temperature for 30 min, and then a light yellow precipitate was collected by filtration, and then washed with excess deionized water and diethyl ether. The precipitate was dried by suction. The crude product was washed with excess deionized water and anhydrous ethanol, and dried in vacuum overnight to obtain [C 16 H 36 N]2[SW2O 14 ] 98.6 g, yield 88.9%.

[0121] Example 10

[0122] Preparation of 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylmethyl ester:

[0123] A clean 2500 mL beaker was taken, and [C 18 H 37 N(CH3)3]3[(OH)SiW3O 18]3.33 g (3 mmol), 4 g (28 mmol) of disodium hydrogen phosphate were placed in a beaker, 500 mL of solvent 1,4-dioxane and 238 mL (1.5 mol) of 3-cyclohexene carboxylic acid-3'-cyclohexene methyl ester were added to the beaker, the system was stirred at 60°C for 15 min, then 185 g of 27.5% hydrogen peroxide (1.5 mol) was added dropwise to the solution, the reaction was carried out for 3 h. After the reaction was completed, the system was cooled to room temperature, the organic phase was collected by liquid separation, the aqueous phase was extracted with ethyl acetate, the catalyst was collected by filtration, the ethyl acetate phase was collected by liquid separation again, the organic phase and the ethyl acetate phase were mixed and rotary evaporated to obtain the product 221.9 g, the conversion rate was 97.2%.

[0124] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarboxylate, characterized in that, Includes the following steps: S1: Dissolve and disperse 3-cyclohexenecarboxylic acid-3'-cyclohexene methyl ester and catalyst in 1,4-dioxane to obtain a mixed solution; S2: At 20~70℃, an oxidant is added dropwise to the mixture to cause 3-cyclohexenic acid-3'-cyclohexene methyl ester to undergo an epoxidation reaction. After the epoxidation reaction of 3-cyclohexenic acid-3'-cyclohexene methyl ester, the mixture is cooled to room temperature, the organic phase is collected by liquid-liquid extraction, and the aqueous phase is extracted with ethyl acetate. The catalyst is recovered by filtration, and the ethyl acetate phase is collected by liquid-liquid extraction again. The organic phase and the ethyl acetate phase are mixed and rotary evaporated to obtain 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexylcarbamate. The catalyst comprises peroxypolytungstate quaternary ammonium salt, wherein the peroxypolytungstate quaternary ammonium salt is [C 18 H 37 N(CH3)3]3[AsW4O 24 ]; The catalyst further includes a support on which the peroxypolytungstate quaternary ammonium salt is supported.

2. The method according to claim 1, characterized in that, The carrier is selected from one or more of metal oxides, diatomaceous earth, zeolite, activated carbon, and silica gel.

3. The method according to claim 1, characterized in that, The mass ratio of 3-cyclohexenecarboxylic acid-3'-cyclohexene methyl ester to the catalyst is 1:0.01~0.

5.

4. The method according to claim 1, characterized in that, The molar ratio of 3-cyclohexenecarboxylic acid-3'-cyclohexene methyl ester to the oxidant is 1:1~5.

5. The method according to claim 1, characterized in that, The oxidant is hydrogen peroxide and / or peracetic acid.

6. The method according to claim 1, characterized in that, Step S1 further includes dispersing the dehydrating agent in an organic solvent.