Base-catalyzed stereoselective thiosulfonylation of ynones for the facile synthesis of thio-functionalized vinyl sulfones

Abstract

The first catalytic vicinal thiosulfonylation of ynones has been developed. Under the catalysis of 1–20 mol% Cs₂CO₃, various ynones underwent the Michael addition/nucleophilic substitution tandem reaction with different thiosulfonates to form C–SO₂ and C–S bonds simultaneously and produced thio-functionalized vinyl sulfones in high yields and with excellent E-selectivity. In addition, on using K₃PO₄ as the base, ynones can couple with trifluoromethyl thiosulfonates through a similar tandem process to afford the corresponding trifluoromethylthiolated products in good to high yields with excellent stereoselectivity.