Toward C2-nitrogenated chromones by copper-catalyzed β-C(sp2)–H N-heteroarylation of enaminones

Abstract

The unconventionally selective β-C(sp²)–H activation of enaminones in the presence of various nitrogen nucleophiles, including azoles and cyclic amines, leading to the synthesis of 2-nitrogenated chromones has been achieved by employing a catalytic system consisting of CuI, I₂, PhI(OAc)₂ and Na₂CO₃. The work discloses a new application of functonal enaminones in the synthesis of valuable heterocyclic scaffolds by switching the reaction pathway via unprecedented regioselectivity.