Cerium(IV) bis(octaethylporphyrinate) and dicerium(III) tris(octaethylporphyrinate): parents of a new family of lanthanoid double-decker and triple-decker molecules
The synthesis, spectral characterization, and crystal structure determination of novel lanthanoid porphyrins, i.e., cerium(IV) bis(octaethylporphyrinate) (Ce(OEP)/sub 2/) and dicerium(III) tris(octaethylporphyrinate)(Ce/sub 2/(OEP)/sub 3/), are described. Synthesis is achieved by prolonged boiling of cerium(III) acetylacetonate (Ce(acac)/sub 3/) and octaethylporphyrin (H/sub 2/(OEP)) in 1,2,4-trichlorobenzene, C/sub 6/H/sub 3/Cl/sub 3/, followed by chromatography on basic alumina. Solutions of reddish-brown, diamagnetic Ce(OEP)/sub 2/ slowly decompose, depositing scarcely soluble, brown paramagnetic Ce/sub 2/(OEP)/sub 3/. The solution structures are deduced from /sup 1/H resonance spectra, and the solid-state structures are proved by X-ray crystallography of monoclinic Ce(OEP)/sub 2/ (P2/sup 1//n) and monoclinic (P2/sub 1//c) or tetragonal (I 4) modifications of bis(trichlorobenzene) or tetrakis(benzene) solvates of Ce/sub 2/(OEP)/sub 3/. The bisporphyrinate is a double-decker while the trisporphyrinates are triple-decker molecules. The cerium ions appear in an approximate square-antiprismatic geometry with Ce-N distances of 2.48 A for the Ce/sup IV/ and of about 2.50 A (external porphyrinate) and 2.75 A (internal porphyrinate) for the Ce/sup III/ sandwich systems. The external porphyrinates are bent away from the cerium ions in a saucer-like shape, whereas the internal porphyrinate is planar. The two mean planes of the 24 core atoms of the individual porphyrin rings lie 3.40 or 3.54 A away from each other in the double-decker or triple-decker, respectively.
- Research Organization:
- Technische Hochschule, Darmstadt, West Germany
- OSTI ID:
- 5658811
- Journal Information:
- J. Am. Chem. Soc.; (United States), Vol. 108:13
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CERIUM COMPLEXES
CHEMICAL PREPARATION
CRYSTAL STRUCTURE
PORPHYRINS
BOND ANGLE
BOND LENGTHS
EXPERIMENTAL DATA
INFRARED SPECTRA
LATTICE PARAMETERS
MASS SPECTRA
NMR SPECTRA
SPACE GROUPS
ULTRAVIOLET SPECTRA
VISIBLE SPECTRA
X-RAY DIFFRACTION
CARBOXYLIC ACIDS
COHERENT SCATTERING
COMPLEXES
DATA
DIFFRACTION
DIMENSIONS
HETEROCYCLIC ACIDS
HETEROCYCLIC COMPOUNDS
INFORMATION
LENGTH
NUMERICAL DATA
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
RARE EARTH COMPLEXES
SCATTERING
SPECTRA
SYNTHESIS
400301* - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)