Ruthenium Complex Fragments As Constituents Of Trinuclear Photoactive Supramolecular Assemblies Based On Hydrogen Bond Association

The reaction of the octahedral complexes cis- or trans-[Ru(C N-tBu)(4)(CN)(2)], (Ru(CN)(2)), with the photochemically active [bis(bipyridyl)bibenzinlidazole-ruthenium(II)], (Ru-biH(2)), component via hydrogen bond association results in the formation of supramolecular aggregates with modified photophysical properties. The first structural characterization of a supramolecular adduct is reported, in which the N-H functions of the ruthenium bound bibenzimidazole ligand via hydrogen bonds serve as an interface directly toward a cyanide ligand acting as a bridge to another transition metal. In addition, the maximum stoichiometry of the supramolecular associates is estimated by NMR titration experiments and association constants of the hydrogen bonded adducts are determined by the decay of the emission intensity during the titration experiments. (c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007.