Classical, nonclassical, and mixed-metal osmium(II) polyhydrides stabilized by the tetraphosphine P(CH[sub 2]CH[sub 2]PPh[sub 2])[sub 3]. H/D isotope exchange reactions promoted by a strongly bound dihydrogen ligand

Journal Article · Wed May 26 04:00:00 EDT 1993 · Inorganic Chemistry; (United States)

DOI:https://doi.org/10.1021/ic00063a028· OSTI ID:5786087

Bianchini, C; Linn, K; Masi, D; Peruzzini, M ^[1]; Polo, A; Vacca, A; Zanobini, F

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1. Istituto per lo Studio della Stereochimica ed Energetica dei Composti di Coordinazione, CNR, Firenze (Italy)

The cis-hydride-[eta][sup 2]-dihydrogen complex [(PP[sub 3])OsH([eta][sup 2]-H[sub 2])]BPh[sub 4] (4), PP[sub 3] = P(CH[sub 2]CH[sub 2]PPh[sub 2])[sub 3], has been prepared by either protonation of the dihydride [(PP[sub 3])OsH[sub 2]] or reaction of the novel dinitrogen complex [(PP[sub 3])OsH(N[sub 2])]-BPh[sub 4] (6) with H[sub 2]. The nonclassical structure of 4 has been established in solution by variable-temperature NMR spectroscopy ([sup 1]H, [sup 31]P), T[sub 1] measurements, and J(HD) values. An X-ray diffraction analysis has shown that the solid-state geometry of the compound is consistent with the nonclassical assignment. Crystals of 4 are triclinic, space group P[bar 1]. In the solid state and in solution at low temperature, [(PP[sub 3])OsH([eta][sup 2]-H[sub 2])][sup +] is octahedral and the hydride and dihydrogen ligands occupy mutually cis positions. The H[sub 2] ligand is trans to the bridgehead phosphorus of PP[sub 3]. At ambient temperature, 4 is highly fluxional. The dynamic behavior of the complex in solution has been studied by variable-temperature [sup 31]P([sup 1]H) NMR spectroscopy. A comparison of the chemical properties, in particular H[sub 2]-displacement reactions, within the series [(PP[sub 3])MH([eta][sup 2]-H[sub 2])][sup +] (M = Fe, Ru, Os) leads to the conclusion that the osmium complex has the strongest interaction with the H[sub 2] ligand. Complex 4 has been found capable of reacting with (CD[sub 3])[sub 2]CO to give the perdeuterated isotopomer 4-d[sub 3] via a keto-enol tautomerization reaction of acetone-d[sub 6]. The isolation and characterization of the mixed osmium-gold dihydride [(PPh[sub 3])OsH([eta][sup 2]-HAu(PPh[sub 3]))]PF[sub 6] has provided experimental evidence for the correctness of the H[sub 2] and HAu(PPh[sub 3]) isolobal relationship.

• OSTI ID: 5786087
• Journal Information: Inorganic Chemistry; (United States), Journal Name: Inorganic Chemistry; (United States) Vol. 32:11; ISSN 0020-1669; ISSN INOCAJ
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
CATIONS
CHARGED PARTICLES
COHERENT SCATTERING
COMPLEXES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFRACTION
HYDRIDES
HYDROGEN COMPOUNDS
IONS
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MOLECULAR STRUCTURE
NUCLEAR MAGNETIC RESONANCE
NUCLEI
ODD-EVEN NUCLEI
OSMIUM COMPLEXES
PHOSPHINES
PHOSPHORUS 31
PHOSPHORUS COMPOUNDS
PHOSPHORUS ISOTOPES
RESONANCE
SCATTERING
STABLE ISOTOPES
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0065-0273 K
TEMPERATURE RANGE 0273-0400 K
TRANSITION ELEMENT COMPLEXES
TRICLINIC LATTICES
X-RAY DIFFRACTION