Vanadium tetrachloride

Chemical reagent used to produce other vanadium compounds

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

UNII

2I17MGM5YJ^Y

CompTox Dashboard (EPA)

DTXSID0064757

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 CH₂Cl₂

Vapor pressure

7.9 Pa

Magnetic susceptibility (χ)

+1130.0·10⁻⁶ cm³/mol

Structure

Coordination geometry

tetrahedral

Dipole moment

0 D

Hazards

Occupational safety and health (OHS/OSH):

Main hazards

toxic; oxidizer; hydrolyzes to release HCl

NFPA 704 (fire diamond)

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 verify (what is ^YN ?)

Infobox references

Chemical compound

Vanadium tetrachloride is the inorganic compound with the formula V Cl₄. This reddish-brown liquid serves as a useful reagent for the preparation of other vanadium compounds.

Synthesis, bonding, basic properties

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 however be prepared indirectly from VF₅ at −78 °C.^[1]

Reactions

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.^[2]

2 VCl₄ + 8 HBr → 2 VBr₃ + 8 HCl + Br₂

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

It is the precursor to vanadocene dichloride.

Organic chemistry

In organic synthesis, VCl₄ is used for the oxidative coupling of phenols. For example, it converts phenol into a mixture of 4,4'-, 2,4'-, and 2,2'-biphenols:^[3]

2 C₆H₅OH + 2 VCl₄ → HOC₆H₄–C₆H₄OH + 2 VCl₃ + 2 HCl

Applications

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.

Safety considerations

VCl₄ is a volatile, aggressive oxidant that readily hydrolyzes to release HCl.

References

^ Tamadon, Farhad; Seppelt, Konrad (2013). "The Elusive Halides VCl₅, MoCl₆, and ReCl₆". Angew. Chem. Int. Ed. 52 (2): 767–769. doi:10.1002/anie.201207552. PMID 23172658.
^ Calderazzo, F.; Maichle-Mössmer, C.; G., Pampaloni; J., Strähle (1993). "Low-temperature Syntheses of Vanadium(III) and Molybdenum(IV) Bromides by Halide Exchange". Dalton Transactions (5): 655–8. doi:10.1039/DT9930000655.
^ O’Brien, M. K.; Vanasse, B. (2001). "Vanadium(IV) Chloride". In Paquette, L. (ed.). Encyclopedia of Reagents for Organic Synthesis. New York, NY: J. Wiley & Sons. doi:10.1002/047084289X.rv001. ISBN 0471936235.