Domino N-H/C-H bond activation: copper-catalyzed synthesis of nitrogen-bridgehead heterocycles using azoles and 1,4-dihalo-1,3-dienes.

Copper-catalyzed tandem coupling of 1,4-dihalo-1,3-dienes with azoles via an N-H bond and its adjacent C-H bond activation has been described. The reaction exhibits good regioselectivity when unsymmetrical 1,4-dihalo-1,3-diene is employed. This method provided a novel route to the synthesis of nitrogen-bridgehead azolopyridine derivatives.