Copper(ii)-mediated metalloradical activation: denitrogenative/decarboxylative annulation to 3-arylimidazo[1,2-a]pyridines using tetrazolo[1,5-a]pyridines and cinnamic acids

Abstract

A new approach involving copper(II)-based metalloradical activation has been explored for the synthesis of diverse 3-arylimidazo[1,2-a]pyridines via denitrogenative/decarboxylative intermolecular annulation of tetrazolo[1,5-a]pyridines with cinnamic acids using trifluoroacetic acid and cesium carbonate in p-xylene. The reaction is facile and is assumed to proceed via a copper-nitrene species.