Substituted bipyridines were efficiently prepared by direct coupling between pyridine N- oxides and halopyridines using a palladium catalyst. Pyridine N-oxides with electron- withdrawing substitutents gave the best yields. This method allows the convenient preparation of 2, 2′-, 2, 3′-, and 2, 4′-bipyridines which are useful as functionalized ligands for metal complexes or as building blocks for supramolecular architectures.
