Visible-Light Photoredox-Catalyzed Thioacetalization of Aldehydes Under Metal-Free and Solvent-Free Conditions

Abstract

A first visible-light photoredox-catalyzed thioacetalization of aldehydes under metal-free and solvent-free conditions is described. Under blue LED irradiation, a reactive thiyl radical was initially generated through single-electron oxidation of thiol, which subsequently reacted with aldehydes to afford dithioacetals following a radical mechanism. The reaction proceeded under ambient conditions, and a wide range of acyclic and cyclic dithioacetal derivatives were afforded in good to excellent yields.