Alkali-Induced Ring-Opening of 2-Amidodihydrofuran and Manganese-Catalyzed Aerobic Dehydrogenation Annulation: Access to Functionalized Oxazole.

A novel and efficient synthesis of functionalized oxazoles from 2-amidodihydrofurans has been achieved by alkali-induced intramolecular C-O bond cleavage and formation using air as a green oxidant. Moreover, these functionalized oxazoles could be readily transformed into the corresponding oxazole-substituted pyrazoles and 2H-azirines.