Tungsten hexacarbonyl

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Molybdenum hexacarbonyl
Chemical name Tungsten hexacarbonyl
Chemical formula C6O6W
Molecular mass 351.90 g/mol
CAS number 14040-11-0
SMILES
Properties
Density and phase 2.65 g/cm3 solid
Solubility in water insoluble
Other solvents sparingly in THF
Melting point 150 °C
Boiling point sublimes
Structure
Coordination
geometry
octahedral
Crystal structure  ?
Dipole moment 0 D
Hazards
MSDS External MSDS
Main hazards flammable, CO source
NFPA 704
Flash point  ? °C
R/S statement R: -
S: 22-24/25
RTECS number  ?
Supplementary data page
Structure and
properties
n, εr, etc.
Thermodynamic
data
Phase behaviour
Solid, liquid, gas
Spectral data UV, IR, NMR, MS
Related compounds
Related compounds Cr(CO)6
Fe(CO)5
Mn2(CO)10
Mo(CO)6
Except where noted otherwise, data are given for
materials in their standard state (at 25 °C, 100 kPa)
Infobox disclaimer and references

Tungsten hexacarbonyl (also called tungsten carbonyl) is the chemical compound with the formula W(CO)6. This complex gave rise to the first example of a dihydrogen complex.[1]

This colorless compound, like its chromum and molybdenum analogues, is noteworthy as a volatile, air-stable derivative of tungsten in its zero oxidation state.

Contents

[edit] Preparation, properties, and structure

W(CO)6 is prepared by the reduction of WCl6 under a pressure of carbon monoxide. It would be rare to prepare this inexpensive compound in the laboratory because the apparatus is expensive and the compound can be purchased cheaply. The compound is relatively air-stable. It is sparingly soluble in nonpolar organic solvents.

W(CO)6 adopts an octahedral geometry consisting of six rod-like CO ligands radiating from the central W atom.

[edit] Reactivity

All reactions of W(CO)6 commence with displacement of some CO ligands in W(CO)6. W(CO)6 behaves similarly to the Mo(CO)6 but tends to form compounds that are kinetically more robust.

A most famous derivative is the dihydrogen complex W(CO)3[P(C6H11)3]2(H2) reported in 1982 by Kubas.[1]

Three of these CO ligands can be displaced by acetonitrile.[2] W(CO)6 has been used to desulfurize organosulfur compounds and as a precursor to catalysts for alkene metathesis.

[edit] Safety and handling

Like all metal carbonyls, W(CO)6 is dangerous source of volatile metal as well as CO.

[edit] References

  1. ^ a b Kubas, G. J., Metal Dihydrogen and σ-Bond Complexes, Kluwer Academic/Plenum Publishers: New York, 2001.
  2. ^ Kubas, G. J. and van der Sluys, L. S., "TricarbonylTris(nitrile) Complexes of Cr, Mo, and W", Inorganic Syntheses, 1990, 28, 29-33.

[edit] External links