Electrochemical C3-methylthiolation of imidazopyridines with dimethyl sulfoxide

An efficient electrochemical methylthiolation reaction of imidazo[1,2-a]pyridines was achieved. The method used DMSO as both the methylthiolating reagent and solvent and KI as both the hydrogen atom transfer reagent and supporting electrolyte. The reaction was performed under transition metal- and chemical oxidant-free conditions. For various substituted 2-arylimidazo[1,2-a]pyridines, C-3 methylthiolation products were obtained regioselectively with good yields. An electrochemical C-3 methylthiolation reaction of imidazo[1,2-a]pyridines was achieved. The method used DMSO as both the methylthiolating reagent and solvent and KI as both the hydrogen atom transfer reagent and supporting electrolyte.