Efficient synthesis of pyrrolo[1,2-α]quinoxalines mediated by ethyl 2-(4-nitrophenyl)azocarboxylate†
Abstract
The synthesis of pyrrolo[1,2-α]quinoxalines is of importance, because they possess a variety of biological activities, and interesting fluorescence/photophysical properties. Multifarious methods for the construction of pyrrolo[1,2-α]quinoxalines have been developed, but there remains no general means to exhibit broad substrate scope with high functional group tolerance under mild conditions. We report herein a practical and efficient oxidative cyclization for pyrrolo[1,2-α]quinoxalines using ethyl 2-(4-nitrophenyl)azocarboxylate.