Tungsten hexachloride
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| Tungsten hexachloride | |
|---|---|
| Image:Tungsten hexachloride.jpg | |
| General | |
| Systematic name | Tungsten(VI) chloride |
| Other names | Tungsten hexachloride |
| Molecular formula | WCl6 |
| SMILES | ? |
| Molar mass | 396.61 g/mol |
| Appearance | dark blue crystals moisture sensitive |
| CAS number | [13283-01-7] |
| Properties | |
| Density and phase | 3.52 g/cm3 |
| Solubility in water | hydrolyzes |
| Other solvents | chlorocarbons |
| Melting point | 275 °C |
| Boiling point | 346.7 °C |
| Structure | |
| Coordination geometry |
octahedral |
| Crystal structure | ? |
| Dipole moment | 0 D |
| Hazards | |
| MSDS | External MSDS |
| Main hazards | oxidizer hydrolysis releases HCl |
| NFPA 704 | |
| R/S statement | R: 34 S: 26-36/37/39-45 |
| RTECS number | YO7710000 |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid |
| Spectral data | UV, IR, NMR, MS |
| Related compounds | |
| Related compounds | Molybdenum(V) chloride chromyl chloride tungsten hexafluoride |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
|
Tungsten hexachloride is the chemical compound with the formula WCl6. This dark violet blue species exists as a volatile solid under standard conditions. It is an important starting reagent in the preparation of tungsten compounds. WCl6 is a rare example of a charge neutral hexachloride, since MoCl6 cannot be prepared. Another example is ReCl6. Better known than WCl6 is the still more volatile WF6.
W(VI) is a d0 ion, so its derivatives are diamagnetic. WCl6 and W(CO)6, both octahedral tungsten compound differ dramatically in properties and bonding. In the WCl6, the chloride ligands are donors in both sigma- and pi sense. In contrast, in W(CO)6, the CO ligands are still sigma donor ligands, but they are also pi-acids.
The chloride ligands in WCl6 can be replaced by many anionic ligands including Br-, NCS-, and RO- (R = alkyl, aryl).
[edit] Safety considerations
WCl6 is an aggressively corrosive oxidant and readily hydrolyzes to release Hydrogen chloride.
[edit] References
- J. W. Herndon "Tungsten(VI) Chloride” in Encyclopedia of Reagents for Organic Synthesis (Ed: L. Paquette) 2004, J. Wiley & Sons, New York. DOI: 10.1002/047084289.
- M. A. Umbreit, K. B. Sharpless “Deoxygenation of Epoxides with Lower Valent Tungsten Halides: trans-Cyclododecene” Organic Syntheses, Coll. Vol. 7, p.121 (1990); Vol. 60, p.29 (1981).
- D. K. Smith, R. L. Landingham, G. S. Smith and Q. Johnson The Crystal Structure of WCl6" Acta Crystalographica (1968). B24, 1563ff.
