One-Pot Synthesis of Keto Thioethers by Palladium/Gold-Catalyzed Click and Pinacol Reactions

An atom-efficient synthesis of keto thioethers was devised via tandem gold/palladium catalysis. The reaction proceeds through a regioselective thiol attack at the beta-position of the alcohol, followed by an alkyl, aryl, or benzyl 1,2-shift. Both acyclic and cyclic systems were studied, in the latter case leading to the ring expansion of cyclic substrates.