Photoredox-Catalyzed Sulfination of Alkyl Bromides: Rapid Access to Diverse Organosulfur Functionality

Abstract

Using simple irradiation with blue light, iridium photoredox catalysis enables both strong oxidations and strong reductions to occur in the same flask, leading to the formation of radical intermediates. Photoredox catalysis has been applied to selectively generate silicon-centered radicals which have the remarkable ability of producing highly reactive alkyl radicals. Here an optimized protocol for the generation of alkyl sulfinates from alkyl bromides via silane-mediated photoredox catalysis is reported. This transformation has been applied to a diverse range of alkyl bromide scaffolds, including representatives from all three classes of aliphatic bromides, offering streamlined syntheses of complex products. Further, various post-functionalization techniques have been developed for the diversification of these sulfinates into a range of medicinally relevant, sulfur-containing functional groups.