Metal-free C–N bond formations: one-pot synthesis of pyrido[2′,1′:2,3]imidazo[4,5-c]cinnolines, benzo[4′,5']thiazolo- and thiazolo[2′,3′:2,3]imidazo[4,5-c]cinnolines

An efficient one-pot synthesis of novel pyrido[2′,1′:2,3]imidazo[4,5-c]cinnoline derivatives has been achieved with moderate to good yields, with two C–N bond formations through C–H functionalization of 2-arylimidazo[1,2-a]pyridines.