Synthesis of 2,4,5-trisubstituted imidazoles catalyzed by [Hmim]HSO4 as a powerful Bronsted acidic ionic liquid

Abstract

An efficient and green procedure for the synthesis of 2,4,5-trisubstituted imidazoles with various aldehydes using a catalytic amount of 1-methylimidazolium hydrogenesulfate as an active and low cost Bronsted acidic room temperature ionic liquid has been developed. The ionic liquid was easily separated from the reaction mixture and was recycled five times without any loss in activity.