Catalytic Electron-Acceptor Mediated C(sp2)–H Sulfoxidation Reactions

Abstract

In recent years, the formation of catalytic Electron Donor-Acceptor (EDA) complexes has been achieved through electron donor redox cycling. However, an electron acceptor catalyst capable of effectively activating the generation of sulfur radicals has yet to be developed. Herein, we present a novel catalytic EDA pathway employing N-Iodosuccinimide (NIS) as catalytic electron acceptor for the C(sp2)-H sulfoxidation, utilizing commercially available and cost-effective thiophenol. This reaction is green, cost-effective, rapid, metal-free and photocatalyst-free, and it exhibits broad substrate scope. Importantly, it circumvents the irreversible consumption of the leaving group by enabling regeneration of the electron acceptor catalyst. In-depth mechanistic studies support this regeneration process and the formation of C(sp2)-H sulfoxidation products.