The transformation strategies between homogeneous and heterogeneous catalysts for the coupling reactions of CO2 and epoxides/olefins

Abstract

CO2 as the C1 building blocks, plays an important role in the carbon cycle of natural. Various efforts have been devoted to the capture and utilization of CO2 with physical, biomass and chemical approaches. Among these methods, the coupling of CO2 with epoxides to prepare cyclic carbonates (CC) is considered to be one of the most promising approaches for conversing CO2 to valuable chemicals. Considering the strong economic potential of CC, it is urgently needed to improve the synthesis conditions and decrease production costs. However, CO2 is a thermodynamically stable molecule, the use of catalysts is therefore indispensable for activation and facilitating the CO2/epoxides coupling reaction in a selective manner under mild conditions. This review covers two kinds of homogeneous catalysts Lewis acid plus nitrogen/phosphorus organic compounds, and their corresponding heterogeneous catalysts mainly focusing on metal organic frameworks and porous organic polymers for the coupling reactions of CO2 and epoxides. Finally, an overview on the future trend of CC synthesis with alkene instead of epoxides to couple CO2 under relative mild conditions would be displayed.