One-Pot Cascade Reactions Leading to Pyrido[2′,1′:2,3]imidazo[4,5-c][1,2,3]triazolo[1,5-a]quinolines under Bimetallic Relay Catalysis with Air as the Oxidant

In this paper, we report an efficient one-pot synthesis of 1,2,3-triazole/quinoline-fused imidazo[1,2-a]pyridines starting from 2-(2-bromophenyl)imidazo[1,2-a]pyridines, alkynes, and sodium azide. This novel method involves a one-pot bimetallic relay-catalyzed cascade process combining azide-alkyne cycloaddition, C-N coupling between 1,2,3-triazole and aryl bromide, and intramolecular cross dehydrogenative C-C coupling between 1,2,3-triazole and imidazo[1,2-a]pyridine. Notable features of this protocol include simple starting materials, sustainable oxidants, reduced synthetic steps, and high efficiency.