2-(1H-1,2,3-triazol-4-yl)-pyridine ligands as alternatives to 2,2'-bipyridines in ruthenium(II) complexes.

The synthesis of a variety of 2-(1H-1,2,3-triazol-4-yl)-pyridines by click chemistry is demonstrated to provide straightforward access to mono-functionalized ligands. The ring-opening polymerization of epsilon-caprolactone initiated by such a mono-functionalized ligand highlights the synthetic potential of this class of bidentate ligands with respect to polymer chemistry or the attachment onto surfaces and nanoparticles. The coordination to Ru(II) ions results in homoleptic and heteroleptic complexes with the resultant photophysical and electrochemical properties strongly dependent on the number of these ligands attached to the Ru(II) core.