Tetrazolates as conjugated bridges for Ir(III)-Ru(II) mixed complexes

The study of the chemistry of tetrazolate metal complexes is the primary thrust of our research program. [1] The scientific activity was initially focused to the preparation of Fe(II) organometallic species containing 5-aryl tetrazolate ligands and extended to the study of a wide range of analogous Ru(II) polypyridyl complexes. The electrochemical features shown by these compounds, together with their highly efficient ElectroChemiLuminescence (ECL) performances, [2,3] prompted the exploitment of new tetrazolate-based Ir(III) cyclometalated complexes. The study of the excited state properties of these Ir(III) complexes showed that all compounds emit highly intense visible light at room temperature, with emission maxima ranging from 480 to 580 nm. Finally, the search for new light-emitting molecules introduces the latest development of our research, which is represented by the synthesis of new tetrazolate-based dinuclear mixed species showing the presence of both Ru(II) and Ir(III) luminophoric systems. [1] Palazzi, A.; Stagni, S.; J. Organomet. Chem. 2005, 690, 2052 and refs. therein; [2] Stagni, S.; Palazzi, A.; Zacchini, S.; Ballarin, B.; Marcaccio, M.; Paolucci F.; Bruno C.; Monari M.; Carano M.; Bard, A.J. Inorg. Chem. 2006, 45, 695; [3] Zanarini, S.; Bard, A.J.; Marcaccio, M.; Palazzi, A;. Paolucci, F.; Stagni, S. J. Phys. Chem. B, 2006, 110, 22551.