Furans Accessed through Visible-Light-Mediated Oxidative [3+2] Cycloaddition of Enols and Alkynes

Visible-light-mediated formation of furans though direct oxidative [3+2] cycloaddition of 1,3-diones and alkynes is described. This protocol provides a simple and mild route to poly-substituted furans in moderate-to-good yields. Preliminary mechanistic studies suggest that this reaction likely follows a radical addition/cyclization pathway.