Metal-Free, Visible-Light-Promoted Decarboxylative Radical Cyclization of Vinyl Azides with N-Acyloxyphthalimides.

A visible-light-mediated decarboxylative cyclization of N-acyloxylphthalimides with vinyl azides has been developed under metal-free conditions. This protocol features mild conditions, a broad substrate scope, and an excellent functional group tolerance, thus providing a facile and efficient access to substituted phenanthridines. Control experiments revealed that the reaction proceeded via a radical process.