Visible‐Light‐Promoted Four‐Component Reaction Based on Catalytic EDA Complexes: Efficient Synthesis of C3 ‐Functionalized Bicyclo[1.1.1]pentane Sulfones

Comprehensive Summary Herein, we report a visible‐light‐mediated, transition‐metal‐free four‐component protocol that synergistically combines the high efficiency of multicomponent reactions (MCRs) with the unique benefits of electron donor‐acceptor (EDA) complex photochemistry. In this transformation, readily available sulfonyl chlorides serve as radical precursors, and thiuram disulfide species, generated in situ from the reaction of carbon disulfide with amines, act as effective radical acceptors. Subsequent radical tandem addition with [1.1.1]propellane, conducted in environmentally benign 2‐methyltetrahydrofuran (2‐MeTHF), delivers a diverse library of 1‐sulfonyl‐3‐dialkylaminothiocarbonylthiol bicyclo[1.1.1]pentane (BCP) products. This protocol realizes the four‐component difunctionalization of [1.1.1]propellane via EDA complex activation, a process that simultaneously forges two C( sp 3 )–S bonds at the bridgehead positions with outstanding chemo‐ and regioselectivity. Beyond establishing a mild and green synthetic route to sulfur‐containing BCP building blocks, this methodology provides a practical means to reduce the reliance of EDA photocatalytic systems on conventional aromatic electron donors. Accordingly, this work is of substantial significance to the advancement of BCP synthetic chemistry and holds considerable promise for applications in pharmaceutical and materials science.