Vanadocene dichloride

Vanadocene dichloride
IUPAC name dichloro bis (η5-cyclopentadienyl) vanadium
Other names Dicyclopentadienyl vanadium dichloride
Identifiers
Abbreviations	Cp2VCl2
CAS number	12083-48-6
RTECS number	YW1580000
Properties
Molecular formula	C10H10Cl2V
Molar mass	252.03 g/mol
Appearance	Green solid
Density	1.7 g/ml
Melting point	Decomp.
Boiling point	Decomp.
Solubility in water	Soluble (Hydrolysis)
Structure
Crystal structure	Monoclinic
Coordination geometry	Tetrahedral
Hazards
R-phrases	R25 R36/37/38 R38
S-phrases	S26 S28 S36/37/39 S45
Main hazards	Irritant
NFPA 704	0 2 1
Related compounds
Related compounds	Titanocene dichloride Zirconocene dichloride Hafnocene dichloride Niobocene dichloride Tanatalocene dichloride Molybdenocene dichloride Tungstenocene dichloride
Y dichloride (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Vanadocene dichloride, dichloro bis(η⁵-cyclopentadienyl)vanadium(IV) is (η⁵-C₅H₅)₂VCl₂ (commonly abbreviated as Cp₂VCl₂). It is a structural analoque of titanocene dichloride but with vanadium(IV) instead of titanium(IV). This compound has one unpaired electron, hence Cp₂VCl₂ is paramagnetic. Vanadocene dichloride is a suitable precursor for variety of bis(cyclopentadienyl)vanadium(IV) compounds.

Reduction of vanadocene dichloride gives vanadocene (C₅H₅)₂V.

Preparation

Cp₂VCl₂ was first prepared by Wilkinson and Birmingham via the reaction of NaC₅H₅ and VCl₄ in THF, followed by work up by extraction with chloroform and hydrogen chloride and recrystallization from toluene.^[1]

Structure

Like titanocene dichloride, this organovanadium compound is currently being investigated as a potential anticancer drug (currently in clinical trials). The mechanism by which it acts is not understood, but some conjecture that it might be due to its interactions with the protein transferrin.^[2]

References

1. ^ G. Wilkinson and J.G. Birmingham (1954). "Bis-cyclopentadienyl Compounds of Ti, Zr, V, Nb and Ta". Journal of the American Chemical Society 76 (17): 4281–4284. doi:10.1021/ja01646a008. 
2. ^ Murthy M. S., Rao L. N., Kuo L. Y., Toney J. H., Marks T. J. (1988). "Antitumor and toxicologic properties of the organometallic anticancer agent vanadocene dichloride.". Inorg. Chimica Acta 152 (2): 117–124. doi:10.1016/S0020-1693(00)83343-5. 

Further reading

• T. Hirao, A. Ogawa, M. Asahara, Y. Muguruma, H. Sakurai (2005), "d,l-Selective Pinacol-Type Coupling Using Zinc, Chlorosilane, and Catalytic Amount of Cp₂VCl₂; dl-1,2-Dicyclohexylethanediol", Org. Synth. 81: 26, http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=v81p0026