Decacarbonyldihydridotriosmium

Decacarbonyldihydridotriosmium
IUPAC name Decacarbonyldihydridotriosmium, decacarbonyl-1κ3C,2κ3C,3κ4C- di-μ-hydrido-1:2κ2H;1:2κ2H -triangulo-triosmium (3 Os—Os)
Identifiers
CAS number	41766-80-7 Y
Properties
Molecular formula	H2Os3(CO)10
Molar mass	852.81 g/mol
Appearance	Deep purple-violet crystals
Density	3.48 g/cm3
Boiling point	decomposes
Solubility in water	no
Solubility in other solvents	decomp in Chlorocarbons
Structure
Coordination geometry	triangular cluster
Hazards
Main hazards	Toxic
Related compounds
Related compounds	Os3(CO)12
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Decacarbonyldihydridotriosmium is a chemical compound with the formula H₂Os₃(CO)₁₀. This purple-violet crystalline air-stable cluster is noteworthy because it is electronically unsaturated and hence adds a variety of substrates.

Structure and synthesis

The trinuclear cluster features an isosceles triangular array of metals with one short edge (r_Os-Os = 2.68 Å), which is spanned by the two hydride ligands, and two longer edges (r_Os-Os = 2.81 Å).^[1] It can be described as Os(CO)₄[Os(CO)₃(μ-H)]₂. The bonding in the Os₂H₂ subunit has been compared to the 3-center, 2e bonding in diborane. It is prepared by purging a solution of Os₃(CO)₁₂ in octane (or other inert solvent of similar boiling point) with H₂.^[2]

Os₃(CO)₁₂ + H₂ → Os₃H₂(CO)₁₀ + 2 CO

Reactions

The cluster reacts with a wide range of reagents under mild conditions. Illustrative is its reaction with [Ni(CO)(C₅H₅)]₂ to give [Ni(C₅H₅)]₃Os₃(CO)₉. With diazomethane, it gives Os₃(CO)₁₀(μ-H)(μ-CH₃), exhibiting an agostic interaction, the first identified in a metal cluster.^[3]

References

1. ^ Melvyn Rowen Churchill, Frederick J. Hollander, and John P. Hutchinson (1977). "Structural studies on polynuclear osmium carbonyl hydrides. 5.Crystal structure and molecular geometry of di-μ-hydrido-decacarbonyltriosmium, (μ-H)₂Os₃(CO)₁₀". Inorg. Chem. 28 (11): 2697–2700. doi:10.1021/ic50177a006. 
2. ^ Kaesz, H. D.; Glavee, G. N.; Angelici, R. J. (1990). "Decacarbonyldi-μ-Hydridotriosmium: Os₃(μ-H)₂(CO)₁₀". Inorganic Syntheses. Inorganic Syntheses 28: 238–39. doi:10.1002/9780470132593.ch60. ISBN 9780470132593. 
3. ^ R. Bruce Calvert, John R. Shapley (1977). "Activation of hydrocarbons by unsaturated metal cluster complexes. 6. Synthesis and characterization of methyldecacarbonylhydridotriosmium, methylenedecacarbonyldihydridotriosmium, and methylidynenonacarbonyltrihydridotriosmium. Interconversion of cluster-bound methyl and methylene ligands". J. Am. Chem. Soc. 99 (15): 5225–5226. doi:10.1021/ja00457a077.