Visible-Light-Promoted EDA Complex Activation for Synthesis of 3-Cyano-4,5-Dihydropyrroles Under Open-Air Conditions.

We report a catalyst-free, open-air synthetic method for 3-cyano-4,5-dihydropyrroles via photoinduced electron donor-acceptor (EDA) complexes using arylglycines and enones in ethyl acetate under mild conditions. This green method avoids metals and toxic additives, accommodates 35 examples including chromone-fused pyrroles and polycyclic indoles, and scales well. Mechanistic investigations confirm the EDA complex pathway upon light irradiation, showcasing EDA chemistry as a sustainable tool for bioactive heterocycle construction.