No-solvent process of epoxidizing cyclohexene with hydrogen peroxide to prepare cyclohexane epoxide

Abstract

The present invention discloses process of epoxidizing cyclohexene with hydrogen peroxide to prepare cyclohexane epoxide. The process includes the following steps: adding hydrogen peroxide and composite catalyst into cyclohexene to react at 20-70 deg.c for 2-10 hr, filtering off catalyst after finishing reaction, separating oil phase, and rectifying to obtain cyclohexane epoxide. The composite catalyst consists of component A and component B, the component A is C-[(R1)n0-(OCH2OCH2)n1-YR2R3R4]m1(Q1)m2Xn2D, and component B is salt. The process of the present invention has the features of no use of solvent, high catalytic activity, high reaction selectivity, high yield, recoverability of component A of catalyst and no pollution.

Description

technical field [0001] The invention relates to a method for preparing epoxycyclohexane by oxidizing cyclohexene with hydrogen peroxide. Background technique [0002] Cyclohexene Oxide is a very versatile organic intermediate, which can be widely used in a wide range of fields such as epoxy resins, surfactants, paints, adhesives, medicines, pesticides, and polymer materials. Due to the requirements of green chemistry, the method of using hydrogen peroxide as a green oxidizing agent has been put on the agenda, but the chemical properties of epoxycyclohexane are active and easily hydrolyzed, so the existing methods for preparing cyclohexene oxide from cyclohexene with hydrogen peroxide are general A large amount of organic solvents such as chloroform, dichloromethane, 1,2-dichloroethane, etc. will be added to slow down the hydrolysis of cyclohexane [Li Kunlan, Zhou Ning, Xi Zuwei. Quaternary in solvents and heteropolyacid salts] The effect of ammonium cations on the control o...

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Problems solved by technology

Due to the requirements of green chemistry, the method of using hydrogen peroxide as a green oxidizing agent has been put on the agenda, but the chemical properties of epoxycyclohexane are active and easily hydrolyzed, so the existing methods for preparing cyclohexene oxide from cyclohexene with hydrogen peroxide are general A large amount of organic solvents such as chloroform, dichloromethane, 1,2-dichloroethane, etc. will be added to slow down the hydrolysis of cyclohexane [Li Kunlan, Zhou Ning, Xi Zuwei. Quaternary in solvents and heteropolyacid salts] The effect of ammonium cations on the control of phase transfer catalysis in cyclohexene epoxidation [J]. Acta Catalytica Sinica, 2002, 23(2): 125-126]. The concentrations are respectively 13%-16% of cyclohexene, 11%-15% of epoxycyclohexane, and 65%-75% of dichloroethane, and the amount of solvent accounts for almost more than 2 / 3. It will reduce the production capacity, increase the recovery cost of solvent and then increase the production cost of epoxycyclohexane. On the other hand, because of the use of toxic and harmful organic solvents, the advantages of hydrogen peroxide as a green oxidant are greatly weakened

In 1996, Kazuhiko Sato et al [AHalide-Free Method for Olefin Epoxidation with 30% ydrogen Peroxide[J].Bull.Chem.Soc.Jpn., 1997, 70(4):905-915.][A Practical Method for Epoxidation ofTerminal Olefins with 30% Hydrogen Peroxide under Halide-Free Conditions[J].J.Org.Chem., 1996,61(23):8310-8311.] have carried out the exploration of preparing olefin epoxide by solvent-free method, but this The method is mainly applied to the preparation of epoxides of terminal olefins, and cannot be used for the preparation of epoxides of olefins sensitive to water, and the catalytic system used in the reaction system is composed of Na 2 WO 4 、[CH 3 (n-C 8 h 17 ) 3 N]HSO 4 , NH 2 CH 2 PO 3 h 2 Composed of a complex system, and the recovery of the catalyst is inconvenient. On the one hand, the inability to effectively recover the catalyst will pollute the product and cause difficulty in product processing; on the other hand, it will increase the production cost and make the process difficult to industrialize.

Xi Zuwei and others have developed a reaction-controlled phase transfer catalyst [Li Kunlan, Xi Zuwei, Sun Yu, etc. A method for preparing epoxycyclohexane by catalytic epoxidation of cyclohexene [P].CN 1401640, 2003-03- 12.][Reaction-Controlled phase-TransferCatalysis for Propylene Epoxidation to Propylene Oxide[J].Science, 2001, 292(5519): 1139-1141.], can combine the high activity of homogeneous catalyst and the ease of heterogeneous catalyst Recovery is combined, but this method has strict requirements on the combination of the organic solvent used in the reaction system and the structure of the quaternary ammonium salt in the catalyst, for example: its catalyst Q 3 PW 4 o 16 In the catalyst, only when the quaternary ammonium salt ion Q is [π-C 5 h 5 NC 164 h 33 ] + , and when the solvent is chloroform, high selectivity and conversion rate can be reached; if other combinations, that is, as other quaternary ammonium salt structures in the catalyst structure, or when using other solvents during the synthesis of epoxy cyclohexane, the reaction Activity or selectivity will obviously reduce, and this catalyzer also can not all reclaim, about 70% of one-time recovery rate, and, because this catalyzer emulsification takes place under solvent-free system, the activity of catalyzer is low, and almost can't reclaim, just can't Applied to the preparation of epoxycyclohexane by solvent-free method

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