Metal‐Free, Visible‐Light‐Promoted Synthesis of 3‐Phosphorylated Coumarins via Radical C−P/C−C Bond Formation

Abstract A metal‐free, visible‐light‐promoted direct difunctionalization of alkynoates was achieved under mild conditions. By employing catalytic quantities of the commercially available Eosin Y (EY) as the photocatalyst and tert ‐butyl‐hydroperoxide (TBHP) as the oxidant, we developed a radical tandem phosphorylation/cyclization reaction to synthesize various 3‐phosphorylated coumarins with high functional group tolerance, moderate to good yields, and excellent regioselectivities. magnified image