Zirconium tetrachloride-SiO2 catalyzed Knoevenagel condensation: A simple and efficient protocol for the synthesis of substituted electrophilic alkenes

Abstract

A facile method for Knoevenagel condensation has been developed by using ZrCl 4 -SiO 2 to afford the corresponding substituted electrophilic alkenes in excellent yields. This method is applicable to a wide range of aldehydes and active methylene compounds. The solid supported catalyst system was reused in further reactions and all the reactions were carried out at 80-85 o C in acetonitrile.