Redox properties of metalloporphyrin dimers
Cyclic and rotated disk voltammetry of two metalloporphyrin dimers, (Ru(OEP))/sub 2/ and (Os(OEP))/sub 2/, exhibit four oxidations and two reductions for each compound which are all chemically and electrochemically reversible on the voltammetric time scale. Comparison of the formal potentials of the six couples suggests that the first two oxidations are metal-centered redox processes; the remaining four couples are likely to be ligand centered. Controlled chemical oxidations using ferricinium hexafluorophosphate, silver tetrafluoroborate, and tris(4-bromophenyl)ammonium hexachloroantimonate cleanly generate the monocations (M(OEP))/sub 2//sup +/ and the dications (M(OEP))/sub 2//sup 2 +/. NMR, ESR, and electronic spectroscopy of these dimeric, cationic products support the assignment of the two oxidations as metal centered. These oxidations permit the preparation of the two series of metalloporphyrin dimers: paramagnetic (M(OEP))/sub 2/ with bond order = 2, paramagnetic (M(OEP))/sub 2//sup +/ with bond order = 2.5, and diamagnetic (M(OEP))/sub 2//sup 2 +/ with bond order = 3.
- Research Organization:
- Stanford Univ., CA
- OSTI ID:
- 5658721
- Journal Information:
- J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 108:11; ISSN JACSA
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
CARBOXYLIC ACIDS
CHEMICAL BONDS
CHEMICAL REACTIONS
CHEMICAL SHIFT
COMPLEXES
DATA
DIMERS
ELECTRON SPECTROSCOPY
ELECTRON SPIN RESONANCE
EXPERIMENTAL DATA
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
INFORMATION
MAGNETIC RESONANCE
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OSMIUM COMPLEXES
PORPHYRINS
REDOX REACTIONS
RESONANCE
RUTHENIUM COMPLEXES
SPECTRA
SPECTROSCOPY
TRANSITION ELEMENT COMPLEXES
VOLTAMETRY