Visible Light-Promoted Cascade Radical Cyclization: Synthesis of 1,4-Diketones Containing Chroman-4-One Skeletons.

Visible light-induced cascade radical cyclization of aroyl chlorides with 2-(allyloxy)-benzaldehyde derivatives is developed. The method takes advantages of un-activated C=C bonds as the acyl radical acceptors and offers a mild and green approach for the synthesis of 1,4-diketons bearing biologically important chroman-4-one skeletons with moderate to good yields.