ZnBr2-BASED CHOLINE CHLORIDE IONIC LIQUID FOR EFFICIENT FIXATION OF CO2 TO CYCLIC CARBONATE

In this work, ZnBr2-based choline chloride (CH) was first investigated to catalyze the synthesis of cyclic carbonates from CO2 and epoxides under solventless conditions. It was demonstrated that ZnBr2-based CH was very efficient and selective. Under the optimum reaction conditions, 99% yield of propylene carbonate was achieved. The catalyst can be reused five times without loss of catalytic activity. It was proved to be very active in a variety of terminal epoxides with CO2. In addition, a synergistic catalytic mechanism by Zn2+ and -OH was proposed.