Vanadium(II) chloride is the inorganic compound with the formula VCl2, and is the most reduced vanadium chloride. Vanadium(II) chloride is an apple-green solid that dissolves in water to give purple solutions.
Properties VCl2 dissolves in water to give the purple hexaaquo ion [V(H2O)6]2+. Evaporation of such solutions produces crystals of [V(H2O)6]Cl2.Martin Pomerantz, Gerald L. Combs, N. L. Dassanayake, "Vanadium Dichloride Solution" Inorganic Syntheses, 1982, vol. XXI, pp. 185–187.
Structure Solid VCl2 adopts the cadmium iodide structure, featuring octahedral coordination geometry. VBr2 and VI2 are structurally and chemically similar to the dichloride. All have the d3 configuration, with a quartet ground state, akin to Cr(III).Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. .
Preparation Solid VCl2 is prepared by disproportionation of vanadium trichloride, which leaves a residue of VCl2 after evaporation of the tetrachloride:Young, R. C.; Smith, M. E. "Vanadium(II) Chloride" Inorganic Syntheses, 1953, volume IV, page 126-127.
The trichloride can also be reduced by heating under flowing hydrogen:
Uses Vanadium dichloride is used as a specialty reductant in organic chemistry. As an aqueous solution, it converts cyclohexylnitrate to cyclohexanone. It reduces phenyl azide into aniline.
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