The Cleavage of a CC Bond in Cyclobutylanilines by Visible‐Light Photoredox Catalysis: Development of a [4+2] Annulation Method

Abstract We report the first example of an intermolecular [4+2] annulation of cyclobutylanilines with alkynes enabled by visible‐light photocatalysis. Monocyclic and bicyclic cyclobutylanilines successfully undergo the annulation with terminal and internal alkynes to generate a wide variety of amine‐substituted cyclohexenes including new hydrindan and decalin derivatives with good to excellent diastereoselectivity. The reaction is overall redox neutral with perfect atom economy.