Visible Light‐Induced Redox‐Neutral Selenocyclization of ortho‐Vinylanilides: Oxygen‐Controlled Synthesis of 4H‐3,1‐Benzoxazines

Abstract

AbstractA visible‐light‐induced selenocyclization of ortho‐vinylanilides to 4H‐3,1‐benzoxazines has been developed under controlled O2 atmosphere. The low O2 content in reaction medium promotes the aerobic selenol oxidation to diselenides for the full use of 2 equiv. selenyl radicals in a redox‐neutral way, avoiding the aerobic oxidation of ortho‐vinylanilides under higher O2 content. The developed visible light‐induced selenocyclization of ortho‐vinylanilides utilizes only visible light with low O2 content, eliminating the use of exogenous photocatalyst and chemical oxidant.