Preparation and spectral electrochemical characterization of dirhodium(II) complexes with bridging 1,8-naphthyridine ligands. X-ray crystal structure of tris(. mu. -acetato)(2,7-bis(2-pyridyl)-1,8-naphthyridine) dirhodium(II) hexafluorophosphate
The preparations and spectral and electrochemical characterizations of several dirhodium(II) complexes of substituted 1,8-naphthyridines are described. These dinuclear complexes are derived by reaction of the appropriate polydentate 1,8-naphthyridine species with dirhodium tetraacetate. The monosubstituted derivatives Rh/sub 2/(O/sub 2/CCH/sub 3/)/sub 3/L/sup +/ include complexes of the crescent-shaped ligand (L) 2,7-bis(2-pyridyl)-1,8-naphthyridine (bpnp) and of 5,6-dihydrodipyrido(2,3-b:3',2'-j)-(1,10)phenanthroline (dinp) and 2-(2-pyridyl)-1,8-naphthyridine (pynp). A disubstituted complex, Rh/sub 2/(O/sub 2/CCH/sub 3/)/sub 2/(pynp)/sub 2//sup 2 +/, and a tetrasubstituted derivative, (Rh/sub 2/(np)/sub 4/)Cl/sub 4/ (np = 1,8-naphthyridine), are also described. Each of these compounds displays electronic spectral bands in the visible region that have been assigned as metal to ligand charge-transfer absorptions not seen in the parent tetraacetate. The electrochemical properties as studied by cyclic voltammetry also differ significantly from those of the tetraacetate with the mono- and disubstituted derivatives displaying both reversible oxidations and reduction. The spectral properties of these complexes are discussed in terms of their probable structures. The structure of the bpnp adduct, (Rh/sub 2/(O/sub 2/CCH/sub 3/)/sub 3/bpnp)PF/sub 6/, has been determined by X-ray diffraction techniques and refined by full-matrix least-squares procedures to a final R index of 0.068. Crystals are tetragonal, space group I4/sub 1/cd, with cell dimensions a = b = 28.720 (14) A, c = 13.906 (5) A, and V = 11470 (9) A/sup 3/ and with Z = 16. The two rhodium atoms are bridged by three acetate groups and the naphthyridine fragment bpnp. The 2-pyridyl nitrogen atoms occupy the axial sites trans to the Rh-Rh bond (Rh-Rh distance = 2.405 (2) A). 2 figures, 8 tables.
- Research Organization:
- Univ. of California, Santa Barbara
- OSTI ID:
- 6922773
- Journal Information:
- Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 23:2; ISSN INOCA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Tunable Rh2(II,II) Light Absorbers as Excited State Electron Donors and Acceptors Accessible with Red/Near-IR Irradiation
Polyaza cavity shaped molecules. 11. Ruthenium complexes of annelated 2,2'-biquinoline and 2,2'-bi-1,8-naphthyridine
Related Subjects
400201 -- Chemical & Physicochemical Properties
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
400400 -- Electrochemistry
ACETATES
ADDUCTS
AROMATICS
AZINES
CARBOXYLIC ACID SALTS
CHEMICAL PREPARATION
CHEMISTRY
COHERENT SCATTERING
COMPARATIVE EVALUATIONS
COMPLEXES
CONDENSED AROMATICS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALLOGRAPHY
DATA
DIFFRACTION
ELECTROCHEMISTRY
EXPERIMENTAL DATA
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
HETEROCYCLIC COMPOUNDS
INFORMATION
INFRARED SPECTRA
LATTICE PARAMETERS
LEAST SQUARE FIT
LIGANDS
MAXIMUM-LIKELIHOOD FIT
MOLECULAR STRUCTURE
NUMERICAL DATA
NUMERICAL SOLUTION
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PHOSPHORUS COMPOUNDS
PHOSPHORUS FLUORIDES
REDOX POTENTIAL
RHODIUM COMPLEXES
SCATTERING
SPACE GROUPS
SPECTRA
STRUCTURAL CHEMICAL ANALYSIS
SYNTHESIS
TETRAGONAL LATTICES
TRANSITION ELEMENT COMPLEXES
ULTRAVIOLET SPECTRA
VOLTAMETRY
X-RAY DIFFRACTION