Photoredox-Catalyzed Phosphine-Mediated Successive Deoxygenation of Sulfonyl Oxime Salts Enables <i>Anti</i>-Markovnikov Hydrothiolation of Alkenes

Stable and easy-to-handle sodium salts of sulfonyl oximes were first identified to proceed via visible-light-driven phophine-mediated successive deoxygenation to realize the <i>anti</i>-Markovnikov hydrothiolation of alkenes, which could serve as an odorless sulfur source. Mechanistic studies revealed that the key thiyl radical intermediate could be generated <i>in</i> <i>situ</i> from the sulfonyl oxime anion via a phosphine-mediated fragmentation and a sequential deoxygenation process. Notably, a wide range of alkenes, including acrylamides, acrylates, vinyl ketones, vinyl sulfones, and acrylonitriles, are competent substrates for this protocol, which is highly beneficial for the construction of structurally diversified organosulfur compounds.