Abstract Chlorothiolation of terminal alkynes with sulfenyl chlorides yields anti-adducts without transition-metal catalysts. In sharp contrast, transition-metal-catalyzed chlorothiolation has not been developed to date, possibly because organosulfur compounds can poison catalyst. Herein, the regio-and stereoselective palladium-catalyzed chlorothiolation of terminal alkynes with sulfenyl chlorides is described. syn- ...