title: Synthesis and redox properties of trinuclear ruthenium-acetylide complexes with tri(ethynylphenyl)amine bridge.
abstract: Novel trinuclear ruthenium complexes have been prepared by using tri(4-ethynylphenyl)amine as a bridging ligand. Cyclic voltammetry of the trinuclear ruthenium complexes revealed stepwise quasi-reversible redox behavior of three ruthenium-acetylide species and the central triphenylamine unit, whereas the mononuclear analog showed two sequential quasi-reversible redox waves. The spectroelectrochemical UV-VIS spectral studies suggested that the 1e- oxidized triruthenium species was stable and showed a characteristic absorption at lambda(max) = 505 nm. Chemical oxidation of the triruthenium complex with ferrocenium hexafluorophosphate led to the isolation of the 1e- oxidized complex, the near-IR spectrum of which revealed an intervalence charge transfer band due to the electronic coupling among three ruthenium species. The 1e(-) oxidized triruthenium complexes can be classified as class II mixed-valence compounds.
authors.affiliation: Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka, 567-0047, Japan. onitsuka@sanken.osaka-u.ac.jp
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Onitsuka
authors.forename: Naoko
authors.initials: N
authors.lastname: Ohara
authors.forename: Fumie
authors.initials: F
authors.lastname: Takei
authors.forename: Shigetoshi
authors.initials: S
authors.lastname: Takahashi