Palladium-Catalyzed Regio- and Stereoselective Coupling of Alkynylsulfones with Alkenes: Access to Dichlorinated Vinyl Sulfones.

A palladium-catalyzed coupling reaction of alkynylsulfones with alkenes has been described, which provides an efficient and practical entry to various functionalized dichlorinated vinyl sulfones. This method features excellent regio- and stereoselectivities, good functional group compatibility, as well as mild reaction conditions. Mechanistic studies suggest that the reaction goes through sequential syn -chloropalladation, alkene insertion, and C(sp 3 )-Cl bond formation processes, and the sulfonyl group is crucial to the stereoselectivity control of the reaction.