title: Structural, redox, and photophysical studies of the tetra(pyridyl)porphyrin complex containing four (2,2'-bipyridine)(2,2':6',2"-terpyridine)ruthenium(II) groups.
abstract: New hybrid complexes of polypyridyl ruthenium and pyridylporphyrins have been prepared by the coordination of pyridyl nitrogens to the ruthenium centers. A 1:4 hybrid complex, [{Ru(bpy)(trpy)}4(mu4-H2Py4P)]8+ ([1]8+) (bpy = 2,2'-bipyridine; trpy = 2,2':6',2"-terpyridine; H2Py4P = 5,10,15,20-tetra(4-pyridyl)porphyrin), has been characterized by the single-crystal X-ray diffraction method. A 1:1 complex, [{Ru(bpy)(trpy)}(H2PyT3P)]2+ ([2]2+) (H2PyT3P = 5-(4-pyridyl)tritolylporphyrin) has also been prepared. The Soret band of the porphyrin ring shifts to longer wavelength with some broadening, the extent of the shift being larger for [1]8+. Cyclic voltammograms of the two complexes show simple overlap of the component redox waves. The complexes are weakly emissive at room temperature, which becomes stronger at lower temperatures. While [1]8+ at >140 K and [2]2+ at 77-280 K show only porphyrin fluorescence, [1]8+ at <140 K shows ruthenium and porphyrin phosphorescence, in addition to the porphyrin fluorescence.
authors.affiliation: Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Kon
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Tsuge
authors.forename: Taira
authors.initials: T
authors.lastname: Imamura
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Sasaki
authors.forename: Shoji
authors.initials: S
authors.lastname: Ishizaka
authors.forename: Noboru
authors.initials: N
authors.lastname: Kitamura