Photoinduced Chemo‐, Site‐ and Stereoselective α‐C(sp3)−H Functionalization of Sulfides

Abstract The ubiquity of sulfur‐containing molecules in biologically active natural products and pharmaceuticals has long attracted synthetic chemists to develop efficient strategies towards their synthesis. The strategy of direct α‐C(sp 3 )−H modification of sulfides provides a streamlining access to complex sulfur‐containing molecules. Herein, we report a photoinduced chemo‐, site‐ and stereoselective α‐C(sp 3 )−H functionalization of sulfides using isatins as the photoredox reagent and coupling partner catalyzed by a chiral gallium(III)‐ N,N ′‐dioxide complex. The reaction proceeds through a verified single‐electron transfer (SET) mechanism with high efficiency, excellent functional group tolerance, as well as a broad substrate scope. Importantly, this cross‐coupling protocol is highly selective for the direct late‐stage functionalization of methionine‐related peptides, regardless of the inherent structural similarity and complexity of diverse residues.