[HSO3-pmim][CH3SO3] Catalyzed One-Pot Protocol for the Synthesis of Coumarins Under Solvent-Free Conditions

Abstract

A mild and efficient protocol for the synthesis of coumarins from different phenol and ethyl acetoacetate via Pechmann reacation using acidic ionic liquids [1-methyl-3-(3-sulfopropyl)- imidazolium methyl sulphate] as catalyst under solvent-free conditions has been developed. The advantages of this protocol are low catalyst loading, better yields, shorter reaction time and environmentally benign.