I2-catalyzed one-pot synthesis of pyrrolo[1,2-a]-quinoxaline and imidazo[1,5-a]quinoxaline derivatives via sp3 and sp2 C-H cross-dehydrogenative coupling

An efficient I-2-catalyzed cascade coupling protocol was developed for the synthesis of pyrrolo[1,2-a]-quinoxaline and imidazo[1,5-a]quinoxaline derivatives via sp(3) and sp(2) C-H cross-dehydrogenative coupling. A nontoxic, readily available catalyst, I-2, and an oxidant, DMSO, were used in this metal-free process. The target compounds were obtained in good-to-excellent yields with a broad substrate scope.