Divergent cyclization of 2-(5-iodo-1,2,3-triazolyl)benzamides toward triazole-fused lactams and cyclic imidates

Abstract

Universal divergent approaches to 1,2,3-triazole-fused quinazolinones and benzoxazine imines have been developed. Both utilize the intramolecular base-mediated cyclization of readily available 2-(5-iodotriazolyl)benzamides. While the O-attack by an ambident carboxamide anion, leading to the formation of cyclic imidates, requires only the presence of a base in a non-polar solvent, the N-attack proceeds as Cu-catalyzed Ullmann coupling. The developed protocols for chemoselective cyclization are operationally simple and cost-efficient, and feature a good functional group compatibility and a much broader scope in comparison with the previously reported approaches.