A one-pot synthesis of [1,2,3]triazolo[1,5-a]quinoxalines from 1-azido-2-isocyanoarenes with high bond-forming efficiency

An efficient approach to prepare 1,2,3-triazolo[1,5-a]quinoxaline scaffolds, starting from 1-azido-2-isocyanoarenes and terminal acetylenes or substituted acetaldehydes, has been developed. In the case of trifluoromethylation triggered cyclization, four chemical bonds, including two C–C and two C–N bonds, were formed consecutively without isolating the triazole intermediate. In addition, these triazo-fused products were readily transformed into diversified quinoxaline derivatives via rhodium-catalyzed carbenoid insertion reactions.