Arylsulfonylacetate as Bifunctional Reagent for Photoredox Catalytic Alkylarylation of Alkynes

The radical difunctionalization of alkynes represents a powerful and straightforward approach for the synthesis of sophisticated molecules. However, the difunctionalization of alkynes mediated by bifunctional reagents remains unexplored, despite significant progress having been made in alkene difunctionalization. Here, we report a novel arylsulfonylacetate skeleton in which aryl rings are attached to acetates through SO2, serving as a powerful bifunctional reagent for the alkylarylation of alkynes under photoredox conditions. This modular bifunctional reagent enables the simultaneous incorporation of a wide range of functional groups, including (hetero)aryl ring and alkyl carboxylate into alkynes, resulting in synthetic valuable all-carbon tetrasubstituted alkene derivatives. This transformation is distinguished by its redox-neutral nature, readily accessible starting materials, compatibility with diverse functional groups and its capacity to facilitate convergent synthesis. The utility of this approach was further demonstrated though the late-stage functionalization of complex molecules, the preparation of fluorescent molecules and anti-cancer drugs