Microwave Assisted [RuCl2(p-cymene)2]2 Catalyzed Regioselective Endo-Tandem Cyclization Involving Imine and Alkyne Activation: An Approach to benzo[4,5]imidazo[2,1-a]pyridine Scaffold

Abstract

A microwave assisted efficient route to the synthesis of benzimidazole fused heterocycles through metal catalyzed endo-cyclization strategy involving imine and alkyne activation has been developed. In the presence of [RuCl2(p-cymene)2]2, a variety of 2-ethynyl aldehydes underwent cascade cyclization with substituted benzenediamines to afford the corresponding benzo[4,5]imidazo[2,1-a] pyridine scaffold in moderate to good yields.