Efficient synthesis of Benzimidazoles using zeolite, alumina and silica gel under microwave irradiation

Abstract

A benzimidazole ring is an important pharmacophore in modern drug discovery and benzimidazoles are very important intermediates in organic reactions, the preparation of benzimidazoles has gained considerable attention in recent years. This article presents a comparative study on the synthesis of benzimidazoles from aromatic, aliphatic and heterocyclic carboxylic acid, benzonitrile and o-phenylenediamine under microwave irradiation and solvent-free conditions are catalyzed by alumina, silica gel and zeolite. All the synthesized compounds are characterized by 1H-NMR, IR, Mass and CHNS analysis.