Lewis Acid-Relayed Singlet Oxygen Reaction with Enamines: Selective Dimerization of Enamines to Pyrrolin-4-ones

reaction in enamine chemistry. For the first time, selective cross-dimerization of two different enamines is achieved. Due to the advantages of mild conditions, high chemoselectivity, and up to 99% yield, a promising strategy has been developed for synthesizing aza-heterocycles under ambient conditions, which can be further applied for the synthesis of imidazolone, quinoxaline, and highly functionalized imine.