多位点离子液体聚合物催化CO_(2)环加成反应研究

Cycloaddition of CO_(2)with epoxides catalyzed by multi-site ionic liquid based hyper-crosslinked polymer

CO_(2)与环氧化物环加成反应制备环状碳酸酯是一条绿色经济的CO_(2)利用途径。针对现有CO_(2)与环氧化物环加成反应中非均相离子液体催化剂活性低和活性组分易流失等问题,设计制备了系列多位点离子液体超交联聚合物HCPs-[DmPhe]Br,研究了多位点协同作用、超交联聚合物组成和结构等因素对其催化CO_(2)与环氧化物环加成反应性能的影响。其中,同时含有双季铵-卤素离子对、羟基和叔胺结构的HCP-[DmPhe]Br-DCX离子液体超交联聚合物催化剂,在1.3 MPa,130℃,8 h的条件下,可实现94%的碳酸丁烯酯收率,且催化剂循环稳定性好,重复使用5次,催化活性没有明显降低。另外,超交联聚合物的多孔结构以及大比表面积促进了离子液体的较好分散,使其与离子液体单体具有相当的活性。该工作对CO_(2)与环氧化物环加成反应高效非均相离子液体催化剂的开发与优化具有一定的借鉴意义。

Cycloaddition of CO_(2)with epoxides to prepare cyclic carbonates is a green and economic path-way for CO_(2)utilization.Given the problems of low activity and easy-leaching of active components of het-erogeneous ionic liquid catalysts,a series of multi-site ionic liquid based hyper-crosslinked polymers were prepared.The synergism effect of various active site as well as composition and structure of the polymers on the catalytic performance of cycloaddition of CO_(2)with epoxides were investigated.The as-prepared catalyst of ionic liquid hyper-crosslinked polymer HCP-[DmPhe]Br-DCX,which contains structures of quaterny ammonium cation-halogen anion pair,hydroxyl and tertiary amine,can achieve 94%yield of butenyl carbonate under 1.3 MPa at 130℃for 8 h.The HCP-[DmPhe]Br-DCX also shows good stabili-ty because its catalytic activity was not decreased when being reused for 5 times.In addition,the porous structure and large specific surface area of the ionic liquid based hyper-crosslinked polymer promote the good dispersion of the ionic liquid,which makes the HCP-[DmPhe]Br-DCX has similar activity as ionic liquid monomer[DmPhe]Br.This work provides a strategy for the development and optimization of high efficiency catalysts for the cycloaddition of CO_(2)with epoxide.