“…Due to the electron count of 14, the [VCp 2 ] + cation gives adducts of general formula [VCp 2 L n ] + by reaction with Lewis bases L. For example, adducts with CO, isocyanides, 6a,b tertiary phosphines,6g nitriles, THF, and acetone 6g,9 have been obtained from bis(cyclopentadienyl)vanadium(III) halides or by direct oxidation of vanadocenes in the presence of the appropriate ligand. Moreover, some authors have reported the reaction of VCp 2 or substituted congeners with metal carbonyls, 6f,− showing that, in some cases, heterobimetallic compounds can be obtained. In the case of the reaction of VCp 2 with V(CO) 6 under a nitrogen atmosphere “a mixture of at least two different compounds was formed”, but the individual components could not be resolved 6f…”