Vanadium(IV) chloride

Vanadium tetrachloride

Names
IUPAC names Vanadium tetrachloride Vanadium(IV) chloride
Identifiers
CAS Number	7632-51-1 Y
3D model (JSmol)	Interactive image
ChemSpider	19956660 Y
ECHA InfoCard	100.028.692
EC Number	231-561-1
PubChem CID	24273
RTECS number	YW2625000
InChI InChI=1S/4ClH.2V/h4*1H;;/q;;;;2*+2/p-4 Y Key: UNUHYFVFMNJHJW-UHFFFAOYSA-J Y InChI=1/4ClH.2V/h4*1H;;/q;;;;2*+2/p-4 Key: UNUHYFVFMNJHJW-XBHQNQODAR
SMILES Cl[V](Cl)(Cl)Cl
Properties
Chemical formula	VCl4
Molar mass	192.75 g/mol
Appearance	bright red liquid, moisture sensitive
Odor	pungent
Density	1.816 g/cm3, liquid
Melting point	−24.5 °C (−12.1 °F; 248.7 K)
Boiling point	148 °C (298 °F; 421 K)
Solubility in water	decomposes
Solubility	soluble in ether, ethanol
Vapor pressure	7.9 Pa
Magnetic susceptibility (χ)	+1130.0·10−6 cm3/mol
Structure
Coordination geometry	tetrahedral
Dipole moment	0 D
Hazards
Main hazards	oxidizer; hydrolyzes to release HCl
NFPA 704	0 3 2 W
Lethal dose or concentration (LD, LC):
LD50 (median dose)	160 mg/kg (rat, oral)
Related compounds
Other anions	vanadium tetrafluoride, vanadium disulfide, vanadium tetrabromide
Other cations	titanium tetrachloride, chromium tetrachloride, niobium tetrachloride, tantalum tetrachloride
Related compounds	vanadium trichloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Vanadium tetrachloride is the inorganic compound with the formula VCl₄. This bright red liquid serves as a useful reagent for the preparation of other vanadium compounds.

With one more valence electron than diamagnetic TiCl₄, VCl₄ is a paramagnetic liquid. It is one of only a few paramagnetic compounds that is liquid at room temperature.

VCl₄ is prepared by chlorination of vanadium metal. VCl₅ does not form in this reaction; Cl₂ lacks the oxidizing power to attack VCl₄. VCl₅ can be prepared indirectly, by metathesis of VF₅ with BCl₃ at −78 °C. In contrast, the heavier analogues NbCl₅ and TaCl₅ are stable and not particularly oxidizing. VF₅ can be prepared directly by fluorination of vanadium metal, reflecting the increased oxidizing power of F₂ vs Cl₂. Indicative of its oxidizing power, VCl₄ releases Cl₂ at its boiling point (standard pressure) to afford VCl₃.

Consistent with its high oxidizing power, VCl₄ reacts with HBr at -50 °C to produce VBr₃. The reaction proceeds via VBr₄, which releases Br₂ during warming to room temperature.

VCl₄ forms adducts with many donor ligands, for example, VCl₄(THF)₂.

It is the precursor to vanadocene dichloride.

VCl₄ is a catalyst for the polymerization of alkenes, especially those useful in the rubber industry. The underlying technology is related to Ziegler–Natta catalysis, which involves the intermediacy of vanadium alkyls.