Visible-Light Induced Isoindoles Formation To Trigger Intermolecular Diels–Alder Reactions in the Presence of Air

Visible-light induced isoindole formation triggered an intermolecular Diels–Alder reaction with dienophiles such as acetylenedicarboxylate and maleimides in the presence of air. The reaction resulted in excellent diastereoselctivity and high yields under mild reaction conditions. This protocol provides an atom-economical, transition-metal-free (TM-free) and straightforward approach to structurally diverse bridged-ring heterocycles from easily accessible molecules.