Immobilization of Chiral Quininium Salt in Ionic Liquid for Enantioselective Epoxidation of Chalcones

An ionic liquid mediated novel protocol for enantioselective epoxidation of α,β-unsaturated ketones employing hydrogen peroxide as an oxidant in the presence of phase transfer catalyst has been developed. The protocol is essentially mild, rapid and environmentally benign employing ambient temperature ionic liquids. The use of ionic liquids facilitates ease of product isolation and catalyst recovery.