Studies in transition metal chemistry. Part II: The addition of organic halides to bis‐cyclopentadienyl vanadium(II)

Several organic halides were found to add to Cp2V(II). The reactions of benzyl chloride, ethyl bromide and methyl iodide were studied in detail. Instead of the expected compound Cp2V(IV)RX (X = Cl, Br, I) the tervalent halide Cp2V(III)X was formed exclusively in the presence of excess alkyl halide. When excess Cp2V(II) was present, however, both Cp2V(III)X and Cp2V(III)R were found as reaction products. The following reaction equations are proposed: a) Cp2V + RX → [Cp2VRX]; b) [Cp2VRX] + Cp2V → Cp2VR + Cp2VX; c) Cp2VR + + RX (excess) → Cp2VX + R2. The compounds Cp2V(III)R and Cp2V(III)X were synthesized and the occurrence of reaction c) was demonstrated.