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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)bibenzimidazole‐ruthenium(II)], (RubiH2), 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.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

The reaction of [Mn(CN)(CO)(tBuNC)4] with MnCl2·4H2O, FeCl3·9H2O, NiCl2·6H2O, and CuCl2·2H2O, respectively, led to the formation of trinuclear heterobimetallic complexes that comprised two manganese moieties, with each coordinating the corresponding metal chloride entities through cyanide bridges. The mixed‐valence trinuclear MnI–CN–MnII–NC–MnI complex as well as the MnI–CN–NiII–NC–MnI derivative have been characterized by X‐ray structure analyses. In the case of the copper and iron compounds that exhibit easily reducable central metal ions, intramolecular electron transfer from manganese(I) to copper(II) or iron(III), respectively, is shown by the presence of metal‐to‐metal charge‐transfer (MMCT) bands as well as by EPR spectroscopy. Moreover, the iron complex shows a subsequent disproportionation, which was demonstrated by the isolation and crystallographic characterization of the reduced species with two manganese(I) complex units coordinating one FeIICl2 moiety.

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Reaction of mixed valence ruthenium tetracarboxylates [Ru(2)(II,III)(R(1)COO)(2)(R(2)COO)(2)Cl] (R(1) = Me, R(2) = 2,4,6-(i)Pr-Ph or R(1) = R(2) = (t)Bu) with two equivalents of the octahedral manganese complex [Mn(I)(CO)(CN)((t)BuNC)(4)] leads to the formation of cyanide bridged heteronuclear coordination compounds of the general formula {[Ru(2)(II,III)(R(1)COO)(2)(R(2)COO)(2)][Mn(I)(CO)(CN)((t)BuNC)(4)](2)}Cl. In solution an intramolecular electron transfer from manganese towards the multiply bonded Ru(2) core occurs that is verified by EPR and IR spectroscopy, magnetic measurements and DFT calculations. Nevertheless, disproportionation of an initially formed {Mn(I)-Ru(2)(II,III)-Mn(I)}(+) adduct into {Mn(II)-Ru(2)(II,III)-Mn(I)}(2+) and {Mn(I)-Ru(2)(II,II)-Mn(I)} species cannot be completely ruled out.