Visible Light-Induced Disulfidation of Internal Alkynes for Stereoselective Access to (E)-Vinyl Sulfides

The stereoselective disulfidation of alkynes remains a compelling yet challenging transformation in organic chemistry. In this study, we report a visible light-induced radical disulfidation of alkynes for the synthesis of (E)-vinyl sulfides. In contrast to previous methods that proceed through nucleophilic or metal-mediated alkyne insertion pathways, this protocol operates via a rarely explored radical mechanism under mild, metal-free conditions. A broad range of alkynes and thiols are well tolerated, affording (E)-vinyl sulfides selectively. This one-pot strategy provides a green and atom-economical approach to stereodefined (E)-vinyl sulfide scaffolds.