Enabling Stereoselective Fluoroalkyl-Sulfonylalkylation of Alkenes and Alkynes Via Photoredox Catalysis

We describe a versatile photocatalytic approach for inter- and intramolecular fluoroalkyl-sulfonylalkylation of carbon−carbon bonds in activated and unactivated alkenes and alkynes. We employ fluoroalkyl sulfinate salts as bifunctional reagents to intro-duce fluoroalkyl and SO2 groups, and alkyl halides to intercept the ensuing sulfonyl intermediates in a process that creates one C(sp3)-C(sp3) and two C(sp3)-S bonds in one step. This method is applicable for the fluoroalkyl-sulfonylalkylation of both alkenes and alkynes bearing a diverse set of functional groups and unsaturated gaseous hydrocarbons. The robustness of the method is also demonstrated by the late-stage diversification of steroids, alkaloids and pharmaceuticals. Mechanistic insights reveal a photoredox-mediated sequential process involving fluoroalkyl radical addition, SO2 incorporation, and subsequent SN2-type displacement.