Enantioselective synthesis of new dimeric chromene derivatives by a ferrocene-copper catalyst system

摘要

Novel 2-iminochromene dimers were prepared in excellent yields (93-99%) and with high to excellent enantioselectivities (89-97% ee) by a simple and efficient method. The precursor 2-[(3-cyano-2H-chromen-2-ylidene)amino] acetates and both racemic and enantioselective 2- iminochromene dimers were disclosed and characterised for the first time.