Chiral metal-containing ionic liquid:Synthesis and applications in the enantioselective cycloaddition of carbon dioxide to epoxides

A series of novel chiral metal-containing ionic liquids(CMILs) consisting of the cation of crown ether-chelated potassium/sodium and the anion of chiral amino acids were designed and synthesized.These new CMILs were used to catalyze the enantioselective cycloaddition of epoxides and carbon dioxide incorporating with the salenCo(OOCCCl3) to generate corresponding chiral cyclic carbonates under mild conditions.These new catalysts can be recycled at least five times without significant loss of activity and enantioselectivity.