Conjugate addition of unactivated thiols to α,β-unsaturated ketones catalyzed by a bifunctional rhenium(V)–oxo complex

ReOCl3(OPPh3)(S(CH3)2) has been found to be an efficient bifunctional catalyst for the 1,4-addition of thiols to α,β-unsaturated ketones. The addition of thiophenol derivatives and alkyl thiols proceeds under mild reaction conditions without pre-activation of the thiol or exogenous base. Reactions of aryl, alkyl, and cyclic enones produce the corresponding β-sulfanyl ketones in good to excellent yield.