Synthesis, X-ray structure, and spectroscopic and electrochemical properties of novel heteronuclear ruthenium-osmium complexes with an asymmetric triazolate bridge

Journal Article · Wed Dec 05 00:00:00 EST 1990 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00181a029· OSTI ID:5890347

Hage, R; Haasnoot, J G; Nieuwenhuis, H A; Reedijk, J ^[1]; De Ridder, D J.A. ^[2]; Vos, J G ^[3]

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1. Leiden Univ. (Netherlands)
2. Univ. of Amsterdam (Netherlands)
3. Dublin City Univ. (Ireland)

The heterodinuclear compounds ((bpy){sub 2}Ru(bpt)Os(bpy){sub 2})(PF{sub 6}){sub 3} (RuOs) and ((bpy){sub 2}Os(bpt)Ru(bpy){sub 2})(PF{sub 6}){sub 3} (OsRu), where Hbpt = 3,5-bis(pyridin-2-yl)-1,2,4-triazole and bpy = 2,2{prime}-bipyridine, have been prepared and characterized. The crystal and molecular structures of ((Ru(bpy){sub 2}){sub 2}(bpt))(CF{sub 3}SO{sub 3}){sub 3}{center dot}4H{sub 2}O and ((bpy){sub 2}Ru(bpt)Os(bpy){sub 2})(CF{sub 3}SO{sub 3}){sub 3}{center dot}4H{sub 2}O have been determined. Only one of the two possible geometrical isomers of the ruthenium dinuclear compound was found in the crystal structure. The two metal centers are coordinated via N(1) and N(4) of the triazole ring. The metal-metal distance is 6.184 (2) {angstrom}. The NMR data revealed that the OsRu isomer has a similar structure, but with the osmium center bound via N(1) and the ruthenium ion coordinated via N(4) of the triazole ring. The electrochemical potentials of the two heterodinuclear compounds are significantly different; for the RuOs compound the oxidation potentials are 0.73 and 1.20 V, while for the OsRu isomer the oxidation potentials are at 0.65 and 1.30 V vs SCE. These differences in electrochemical behavior between the two isomeric RuOs and OsRu compounds suggest that the N(1) atom of the triazole ring is a better {sigma}-donor than N(4). The mixed-valence dinuclear systems all exhibit rather intense intervalence transition (IT) bands in the near-infrared region, suggesting a moderately strong metal-metal interaction for the bpt systems. A correlation between the energy of the IT bands of the mixed-valence dinuclear complexes and the oxidation potentials has been observed.

• OSTI ID: 5890347
• Journal Information: Journal of the American Chemical Society; (United States), Vol. 112:25; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
OSMIUM COMPLEXES
CHEMICAL PREPARATION
MOLECULAR STRUCTURE
RUTHENIUM COMPLEXES
BOND ANGLE
BOND LENGTHS
ELECTROCHEMICAL CELLS
ELECTRON TRANSFER
NMR SPECTRA
PYRIDINES
REDOX POTENTIAL
TRIAZOLES
ULTRAVIOLET SPECTRA
X-RAY DIFFRACTION
AZINES
AZOLES
COHERENT SCATTERING
COMPLEXES
DIFFRACTION
DIMENSIONS
HETEROCYCLIC COMPOUNDS
LENGTH
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
SCATTERING
SPECTRA
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties
400400 - Electrochemistry