Copper-catalyzed C–H ethoxycarbonyldifluoromethylation of imidazoheterocycles†
Abstract
A regioselective copper-catalyzed ethoxycarbonyl-difluoromethylation of imidazo[1,2-a]pyridines has been developed through sp2 C–H bond functionalization with BrCF2CO2Et under ambient air. A series of ethoxycarbonyldifluoromethylated imidazo[1,2-a]pyridines with broad functionalities have been synthesized. This methodology is also applicable to imidazo[2,1-b]thiazole and benzo[d]imidazo[2,1-b]thiazole.