CN-121991101-A - Method for synthesizing carbonic ester by catalyzing metal coordination hypercrosslinked polymeric ionic liquid

Abstract

The invention relates to a method for preparing carbonic ester by catalyzing CO 2 and epoxide with metal coordination hypercrosslinked polymeric ionic liquid. According to the method, triphenylphosphine and p-dibenzyl bromide are used as cross-linking agents to generate triphenylphosphine-benzylphosphine bromide ionic liquid through ionization reaction, triphenylphosphine and anhydrous ferric trichloride are added to obtain super-crosslinked polymeric ionic liquid through Friedel-crafts alkylation reaction, then metal salt and triphenylphosphine in the super-crosslinked polymeric ionic liquid are added to carry out metal coordination, and under the conditions that the preferable metal coordination super-crosslinked polymeric ionic liquid is 0.01-0.06 mol% of the consumption of reactants, the reaction temperature is 30-110 ℃, the reaction pressure is 1MPa, and the reaction time is 0.5-4 h, the yield of the carbonate synthesized by CO 2 and epoxide can reach 96%. Compared with the super cross-linked polymeric ionic liquid, the metal coordination super cross-linked polymeric ionic liquid catalyst has the advantages of obviously improved catalytic performance, easy separation of products, strong thermal stability and the like, and can be recycled for multiple times without adding additional cocatalysts and other solvents.

Inventors

• CHENG WEIGUO
• FU MENGQIAN
• SU QIAN
• LI YUNONG
• YANG ZIFENG
• ZHAO QIANMENG
• LIU WEN
• ZHANG SUOJIANG

Assignees

• 中国科学院过程工程研究所

Dates

Publication Date

20260508

Application Date

20241104

Claims (7)

1. 1. A preparation method of a metal coordination hypercrosslinked polymer ionic liquid catalyst is characterized in that the metal coordination hypercrosslinked polymer ionic liquid catalyst is synthesized through two steps, wherein the first step is to form the hypercrosslinked polymer ionic liquid through ionization and Friedel-crafts alkylation reaction by triphenylphosphine and p-dibenzyl bromide, the catalyst has a structure shown in a formula 1, and the second step is to coordinate triphenylphosphine in the hypercrosslinked polymer ionic liquid synthesized in the formula 1 as a coordination site to form the metal coordination hypercrosslinked polymer ionic liquid through coordination with metal salt, and the catalyst has a structure shown in a formula 2 The catalyst is used for synthesizing carbonic ester by CO 2 and epoxide.
2. 2. The method for preparing the metal coordination hypercrosslinked polymeric ionic liquid catalyst as claimed in claim 1, which is characterized by comprising the following steps: Adding p-dibenzyl bromide into triphenylphosphine and solvent 1, 2-dichloroethane under inert gas atmosphere to generate triphenylphosphine ion liquid, then adding anhydrous ferric trichloride to make monomer undergo the process of Friedel-crafts alkylation and quick polymerization so as to obtain correspondent super-crosslinking polymerization ion liquid, then adding tetrahydrofuran into a certain quantity of super-crosslinking polymerization ion liquid to make it swell for 4 hr, then adding metal salt, and making the triphenylphosphine and metal salt in the super-crosslinking polymerization ion liquid coordinate to form metal coordination type super-crosslinking polymerization ion liquid, drying under the vacuum condition of 70 deg.C to constant weight so as to remove small quantity of solvent.
3. 3. The method for preparing the metal coordination hypercrosslinked polymeric ionic liquid catalyst as claimed in claim 1, wherein the method for synthesizing carbonate is as follows: And (3) carrying out cycloaddition reaction on CO 2 and epoxide under the catalysis of metal coordination hypercrosslinked polymeric ionic liquid to obtain the corresponding carbonate.
4. 4. The method for preparing the metal coordination hypercrosslinked polymer ionic liquid catalyst according to claim 3, wherein the cycloaddition reaction temperature is 30-110 ℃.
5. 5. The method for preparing the metal coordination hypercrosslinked polymer ionic liquid catalyst according to claim 3, wherein the reaction time of cycloaddition reaction is 0.5-4 h.
6. 6. The method for preparing the metal coordination hypercrosslinked polymer ionic liquid catalyst according to claim 3, wherein the hypercrosslinked polymer ionic liquid catalyst accounts for 0.01-0.08 mol% of the mole number of epoxide.
7. 7. The method for preparing a metal coordination hypercrosslinked polymer ionic liquid catalyst as claimed in claim 3, wherein the epoxide is any one of ethylene oxide, propylene oxide, butylene oxide, epichlorohydrin, styrene oxide, cyclohexane oxide and cyclopentane oxide; The preparation method comprises the following steps: Placing epoxide and a catalyst in a closed reaction kettle, maintaining the temperature of the reaction kettle at a certain target temperature of 30-110 ℃, introducing CO 2 gas into the reaction kettle, maintaining the pressure in the reaction kettle within a range of 1MPa, and performing cycloaddition reaction on a reaction system for 0.5-4 h to obtain carbonate. The yield of the carbonic ester is 45.5% -97.6%.

Description

Method for synthesizing carbonic ester by catalyzing metal coordination hypercrosslinked polymeric ionic liquid Technical Field The invention relates to the technical field of green clean catalysis for CO 2 trapping and efficient conversion, in particular to a method for synthesizing a metal coordination type super-crosslinking polymerization ionic liquid structure catalyst, which can catalyze CO 2 and epoxide to synthesize carbonate through cycloaddition reaction under a mild condition. Background Carbon dioxide (CO 2) is a major component of greenhouse gases and is also a rich and readily available C1 resource. Efficient conversion and high-value utilization of CO 2 as a raw material have been a hot topic in academia and industry. Under the induction of high-energy epoxide molecules, CO 2 can be efficiently activated through cyclization reaction, so that carbonate is synthesized, and the method is a representative atomic economic method with high-efficiency conversion and high-value utilization. The product, namely the cyclocarbonate, is very popular in domestic and foreign markets due to the wide application of the cyclocarbonate in the aspects of lithium ion battery electrolyte, polycarbonate monomer, medical production, green additives and the like. However, the conventional cyclization reaction often requires high temperature and high pressure (100-120 ℃ and 2-5 MPa) to ensure the reaction efficiency, so that the process is difficult to control and the energy consumption is high. Many researchers and institutions have developed homogeneous catalytic systems represented by metal salts, organic bases and metal complexes, and heterogeneous catalytic systems represented by metal oxides, ion exchange resins, modified molecular sieves and immobilized catalysts. Although the reaction temperature and pressure are reduced to some extent, the activity and stability under the reaction conditions cannot be simultaneously achieved, and no breakthrough progress has been made in efficient catalysis under mild conditions (< 90 ℃). Compared with the traditional catalyst, the ionic liquid has higher catalytic activity through structural design and functionalization, and can effectively reduce the reaction temperature. However, the agglomeration effect of homogeneous ionic liquids results in a low utilization efficiency of ionic liquids in the reaction system, resulting in a large amount of ionic liquid consumed to obtain high catalytic activity and difficult separation. The immobilized ionic liquid catalytic system can effectively simplify the separation process, but the existence of a carrier interface slows down the diffusion speed of macromolecule reaction molecules to the active site of the catalyst, so that the catalytic efficiency of the immobilized catalyst is far lower than that of the homogeneous ionic liquid. Disclosure of Invention The invention aims at providing a super cross-linked polymeric ionic liquid catalyst with high cross-linking degree, which is formed by polymerization of ionic liquid monomers and cross-linking agents through Friedel-crafts alkylation, and then metal coordination super cross-linked polymeric ionic liquid is formed through coordination with metal salts. The method can realize the purpose of efficiently synthesizing the carbonic ester from the CO 2 and the epoxy compound under mild conditions without solvent and auxiliary agent, and the synthetic route adopted by the method is simple and easy to operate, and the catalyst activity can be easily regulated by regulating and controlling the proportion of raw material monomers, so that the method has the advantages of high catalytic yield, strong substrate universality, mild reaction conditions, simplicity in recovery and separation and the like. The invention aims to provide a metal coordination hypercrosslinked polymeric ionic liquid with high catalytic capability for synthesizing carbonic ester from CO 2 and epoxide. The metal coordination hypercrosslinked polymeric ionic liquid catalyst has a structure as shown in formula 1: The second object of the invention is to provide a metal coordination polymer ionic liquid which acts on CO 2 and epoxide to synthesize carbonic ester. The triphenylphosphine ion liquid has the characteristics of strong designability, easy synthesis, effective reduction of reaction activation energy and the like, in addition, triphenylphosphine can be coordinated with metal salt to be introduced into the polymerized ion liquid, the problem of separation and recovery of a catalyst can be easily solved, and the flexible regulation and control of the distribution of active centers can be realized by adjusting the proportion of the monomer and the cross-linking agent, so that the catalytic effect of the ion liquid and the metal is maximized. Preferably, the monomer and the cross-linking agent are prepared by Friedel-crafts alkylation reaction polymerization in a certain proportion. The preparation method of the metal