Copper-Catalyzed Aerobic Oxidative [2 + 3] Cyclization/Aromatization Cascade Reaction: Atom-Economical Access to Tetrasubstituted 4,5-Biscarbonyl Imidazoles

An atom-economical method for accessing tetrasubstituted 4,5-biscarbonylimidazoles by reaction between glycine derivatives and 5-alkoxyoxazoles is reported. The method, which involves a copper-catalyzed aerobic oxidative [2 + 3] cyclization/aromatization cascade process, starts from readily available and inexpensive materials, uses molecular oxygen as a co-oxidant, and has a broad substrate scope.