I₂/TBPB Mediated Oxidative Reaction to Construct of Imidazo[1,5‐α]pyridines under Metal‐Free Conditions

Abstract

Abstract A new method for the synthesis of imidazo[1,5‐α]pyridines, one of the most important N‐heterocyclic compounds due to their wide application, was reported in this study. Specifically, using I 2 as a non‐metal catalyst and TBPB as an oxidant can efficiently facilitate the synthesis and avoid the use of a metal catalyst. The reaction between ethyl ( E )‐2‐(benzylideneamino)acetate and pyridine represents an unprecedented 1,3‐diolar cycloaddition in highly straightforward process with great value.