Visible-light-driven Na2CO3-enabled photocatalyst- and metal-free selective thio- and selenosulfonylation of unactivated alkenes

Atom transfer radical addition (ATRA) of alkenes with thiosulfonates is a powerful strategy to construct valuable thioalkylsulfones. However, these methods employ complex catalytic systems, a high loading of rare-earth- or noble-metal-based catalyst, a stoichiometric oxidant or an extra photocatalyst. Herein, we describe a visible-light-driven Na 2 CO 3 -enabled vicinal thio- and selenosulfonylation of unactivated alkenes under photocatalyst-free, metal-free, external oxidant-free and mild conditions. This approach features excellent regio- and stereoselectivities, a simple and convenient procedure, broad substrate scope, 100% atom economy, and late-stage functionalization of complex molecules. Preliminary mechanistic studies reveal that the formation of an electron donor-acceptor (EDA) complex is critical to the success of this transformation. An efficient and convenient visible-light-induced ATRA approach for the thio- and selenosulfonylation of unactivated alkenes was developed. The formation of an electron donor-acceptor (EDA) complex is critical to the success of this transformation to avoid the utilization of external photocatalysts, metals and oxidants.