Cluster synthesis. 38. Formation of high-nuclearity platinum-osmium cluster complexes. Synthesis, structural characterizations, and interrelationships of Pt[sub 4]Os[sub 6](CO)[sub 22](COD), Pt[sub 5]Os[sub 6](CO)[sub 21](COD)[sub 2], Pt[sub 4]Os[sub 6](CO)[sub 19](COD)[sub 2], and Pt[sub 7]Os[sub 6](CO)[sub 21](COD)[sub 2] (COD = cycloocta-1,5-diene)

Journal Article · Wed Jun 10 00:00:00 EDT 1992 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00038a046· OSTI ID:7180644

Adams, R D; Lii, Jauching; Wu, Wengan ^[1]

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1. Univ. of South Carolina, Columbia (United States)

The chemistry of heteronuclear cluster complexes containing Pt has attracted a great deal of interest becasue of the importance of Pt alloys to the process of catalytic petroleum reforming. Three new high-nuclearity Pt-Os carbonyl cluster complexes Pt[sub 4]Os[sub 6](CO)[sub 22](COD) (2), Pt[sub 5]Os[sub 6](CO)[sub 21](COD)[sub 2] (3), and Pt[sub 4]Os[sub 6](CO)[sub 19](COD)[sub 2] (4) were obtained in 17%, 13%, and 9% yields, respectively, from the pyrolysis of Pt[sub 2]Os[sub 3](CO)[sub 10](COD)[sub 2] (1) under a CO atmosphere at 128C. Compounds 2-4 were characterized by IR, [sup 1]H NMR, and single-crystal X-ray diffraction analyses. Compound 2 consists of two Pt[sub 3]Os[sub 3] octahedra sharing a Pt[sub 3] triangular face. A Pt(COD) group caps one of the Os[sub 3] triangular faces. Compound 3 is structurally similar to compound 2 but has an additional Pt(COD) group capping one of the PtOs[sub 2] triangular faces. The cluster of compound 4 can be viewed as a meta-bicapped Pt[sub 2]Os[sub 4] octahedron with an additional Pt(COD) group capping a PtOs[sub 2] traingle to one of the capping groups on the octahedron and a Pt(COD) group bridging the Pt-Pt edge of the octahedron. Compound 2 was converted to 4 in 65% yield, when it was irradiated in the presence of COD. When compound 2 was treated with 1 equiv of trimethylamine N-oxide and 2 equiv of Pt(COD)[sub 2], compound 3 and a new higher nuclearity platinum-osmium carbonyl complex Pt[sub 7]Os[sub 6](CO)[sub 21](COD)[sub 2] (5; 8% yeild) were obtained. Compound 5 was characterized by a single-crystal X-ray diffraction analysis. It was formed by the loss of one CO from 2 and the addition of three Pt atoms and one COD ligand. Compound 2 was converted to the known compound Pt[sub 4]Os[sub 6](CO)[sub 21](COD)([mu]-H)[sub 2] in good yield (79%) by reacting with trimethylamine N-oxide and hydrogen.

• OSTI ID: 7180644
• Journal Information: Inorganic Chemistry; (United States), Vol. 31:12; ISSN 0020-1669
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
02 PETROLEUM
OSMIUM COMPLEXES
CHEMICAL PREPARATION
STRUCTURAL CHEMICAL ANALYSIS
PLATINUM COMPLEXES
BOND ANGLE
BOND LENGTHS
CARBONYLS
CATALYSTS
CATALYTIC REFORMING
INFRARED SPECTRA
LIGANDS
MOLECULAR STRUCTURE
MONOCRYSTALS
NMR SPECTRA
ORGANOMETALLIC COMPOUNDS
PETROLEUM
PYROLYSIS
TRANSITION ELEMENT COMPLEXES
X-RAY DIFFRACTION
CHEMICAL REACTIONS
COHERENT SCATTERING
COMPLEXES
CRYSTALS
DECOMPOSITION
DIFFRACTION
DIMENSIONS
ENERGY SOURCES
FOSSIL FUELS
FUELS
LENGTH
ORGANIC COMPOUNDS
REFORMER PROCESSES
SCATTERING
SPECTRA
SYNTHESIS
THERMOCHEMICAL PROCESSES
400201* - Chemical & Physicochemical Properties
020400 - Petroleum- Processing