Copper-catalyzed direct sulfenoamination of saturated ketones via in situ formed enaminones.

A sequential and efficient protocol for the synthesis of α-thiolated enaminones has been developed using copper-TEMPO systems. This reaction features a broad substrate scope to afford the desired product in good to excellent yields with high stereoselectivity. A preliminary mechanistic study suggests that the in situ formed enaminone acts as the key intermediate.