β-CD/CuI catalyzed regioselective synthesis of iodo substituted 1,2,3-triazoles, imidazo[1,2-a]-pyridines and benzoimidazo[2,1-b]thiazoles in water and their functionalization

Abstract

An environment benign process has been developed for the regioselective synthesis of 5-iodo-1,4-disubstituted-1,2,3-triazoles catalyzed by CuI/β-CD in water. Moreover, the process was manifested for the efficient synthesis of 2-iodo-imidazo[1,2-a]pyridines and 2-iodo-benzoimidazo[2,1-b]thiazoles in aqueous medium. Additionally, the iodinated derivatives were successfully modified via palladium catalyzed coupling reactions. The salient features of this methodology are in-situ formation of 1-iodoalkyne & alkyl/aryl azide under mild reaction conditions, high regio-selectivity and use of water as a greener solvent.