Tandem Cu(I)-Catalyzed Dipolar Cycloaddition–C–H Activation for the In-Flow Synthesis of N-Pyridyl-5-amino-1,2,3-triazole-4-carboxylates

Abstract

A telescoped process under continuous flow conditions is described for the synthesis of N-pyridyl-5-amino-1,2,3-triazole-4-carboxylate derivatives catalyzed by copper salts in a packed bed reactor. The synthetic approach takes first advantage of click chemistry, specifically relying on Cu(I)-catalyzed 1,3-dipolar azide–alkyne cycloaddition (CuAAC), to achieve the efficient and selective assembly of a triazole ring, followed by a copper-mediated C–H activation, that substitutes an inert C–H bond with a C–N bond, providing an environmentally acceptable and cost-effective strategy for synthesizing highly functionalized organic molecules.