Vanadium(III) bromide

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Vanadium(III) bromide
Image:Vanadium(III) bromide.jpg
IUPAC name Vanadium(III) bromide
Other names Vanadium tribromide
Identifiers
CAS number [13470-26-3]
Properties
Molecular formula VBr3
Molar mass 290.654 g/mol
Appearance Gray-brown solid
Density 4 g/cm3, solid
Solubility in water soluble
Solubility in other solvents soluble in THF
(forms adduct)
Structure
Coordination
geometry
octahedral
Related compounds
Other anions Vanadium(III) chloride
Other cations Titanium(III) chloride
Related compounds MoBr3
VCl2
VCl4
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Vanadium(III) bromide, also known as vanadium tribromide, is VBr3. In the solid-state, this species is a polymeric with octahedral vanadium(III) surrounded by six bromide ligands.

VBr3has been prepared by treatment of VCl4 with HBr:

2 VCl4 + 8 HBr → 2 VBr3 + 8 HCl + Br2

The reaction proceeds via the unstable vanadium(IV) bromide, VBr4, which releases Br2 at room temperature.[1]

Like VCl3, VBr3 forms red-brown soluble complexes with dimethoxyethane and THF, such as mer-VBr3(THF)3.[2]

Aqueous solutions prepared from VBr3 contain the salt trans-[VBr2(H2O)4]+. Evaporation of these solutions give the salt trans-[VBr2(H2O)4]Br.[3]

[edit] References

  1. ^ Calderazzo, F.; Maichle-Mossmer, C.; Pampaloni, G. and Strähle, J., "Low-temperature Syntheses of Vanadium(III) and Molybdenum(IV) Bromides by Halide Exchange", Journal of the Chemical Society, Dalton Transactions, 1993, pages 655-8.
  2. ^ G. W. A. Fowles, G. W. A.; Greene, P. T.; Lester, T. E. "Ether Complexes of Tervalent Titanium and Vanadium" J. inorg, nucl. Chem., 1967. Vol. 29. pp. 2365 to 2370.
  3. ^ Donovan, W. F.; Smith, P. W. "Crystal and Molecular Structures of Aquahalogenovanadium(1ii) Complexes. Part 1. X-Ray Crystal Structure of trans-Tetrakisaquadibromovanadium(III) Bromide Dihydrate and the lsomorphous Chloro-compound" Journal of the Chemical Society, Daltor Transactions." 1975, pages 894-896.

[edit] Further reading

  • Stebler, A.; Leuenberger, B.; Guedel, H. U. "Synthesis and crystal growth of A3M2X9 (A = Cs, Rb; M = Ti, V, Cr; X = Cl, Br)" Inorganic Syntheses (1989), volume 26, pages 377-85.