A facile tandem synthesis of α-benzyl benzimidazole acetonitriles

Abstract

An efficient and convenient tandem method for the synthesis of α-benzylbenzimi dazoleacetonitriles has been developed. In this method, a benzimidazoleacetonitrile 1 was condensed with an aromatic aldehyde in the presence of basic alumina under solvent-free conditions by simple physical grinding of reactants using a mortar and pestle. Subsequent reduction of the in situ formed acrylonitrile derivative with NaBH4 in 95% ethanol at room temperature gives the corresponding 2-(1H-benzimidazol-2-yl)-3-aryl- propionitrile 3 by regiospecific reduction of the double bond. ©ARKAT USA, Inc.