Determination of the structure of [Os([eta][sup 2]-H[sub 2])en[sub 2]CH[sub 3]CO[sub 2]]PF[sub 6] by X-ray and neutron diffraction

Journal Article · Wed May 18 00:00:00 EDT 1994 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00089a024· OSTI ID:7165998

Hasegawa, Tai; Li, Z; Taube, H ^[1]; Parkin, S; Hope, H ^[2]; McMullan, R K; Koetzle, T F ^[3]

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1. Stanford Univ., CA (United States)
2. Univ. of California, Davis, CA (United States)
3. Brookhaven National Lab., Upton, NY (United States)

The structure of [Os([eta][sup 2]-H[sub 2])en[sub 2]CH[sub 3]CO[sub 2]]PF[sub 6] (1) has been studied by X-ray diffraction at 120 K and neutron diffraction at 165 K. Compound 1 belongs to a series of dihydrogen complexes of osmium(II) amines, exhibiting an extensive range in the strength of the H-H interaction as judged by the wide variation in observed J[sub H-D] coupling constants. The ethylenediamine ligands in I have a trans arrangement. The H[sub 2] and the acetate ligands occupy positions on opposite sides of the OsN[sub 4] plane, giving overall approximately octahedral coordination. Consistent with the relatively low J[sub H-D] value (9.0 Hz), the H-H distance in 1.134(2) [angstrom] as determined by neutron diffraction, is unusually long and approaches that of 1.357(7) [angstrom] found in the polyhydride ReH[sub 7][P(p-tolyl)[sub 3]][sub 2]. It is presumed that I may represent an intermediate stage in the oxidative addition of dihydrogen at transition-metal centers. The Os-H distances in 1.1.59(1) [angstrom] and 1.60(2) [angstrom], are shorter than those in the classical osmium polyhydride OsH[sub 4](PMe[sub 2]Ph)[sub 3] (mean Os-H 1.659(3) [angstrom]) lending support to the assertion that the Os([eta][sup 2]-H[sub 2]) interaction is relatively strong. Crystal data are provided. 46 refs., 3 figs., 2 tabs.

• DOE Contract Number: AC02-76CH00016
• OSTI ID: 7165998
• Journal Information: Journal of the American Chemical Society; (United States), Vol. 116:10; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ORGANIC FLUORINE COMPOUNDS
CRYSTALLOGRAPHY
MOLECULAR STRUCTURE
NEUTRON DIFFRACTION
NUCLEAR MAGNETIC RESONANCE
X-RAY DIFFRACTION
OSMIUM COMPLEXES
AMINES
CHEMICAL BONDS
COMPILED DATA
LIGANDS
COHERENT SCATTERING
COMPLEXES
DATA
DIFFRACTION
INFORMATION
MAGNETIC RESONANCE
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
RESONANCE
SCATTERING
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties
400102 - Chemical & Spectral Procedures