Cooperative iodine and photoredox catalysis for direct oxidative lactonization of carboxylic acids

Abstract

A new method for the formation of γ- and δ-lactones from carboxylic acids through direct conversion of benzylic C–H to C–O bonds is described. The reaction is conveniently induced by visible light and relies on a mild cooperative catalysis by the combination of molecular iodine and an organic dye.