Zwitterionic, ring-borylated vanadium(III) complexes from [Cp2VCO] and B(C6F5)3

The reaction of the vanadium(II) carbonyl [Cp2V(CO)] and B(C6F5)(3) resulted in formation of zwitterionic, ring-borylated vanadium(III) complexes [(Cp)(C5H4B(C6F5)(3))V] (3) and [(Cp)(C5H4B(C6F5)(3))V(CO)(2)] (4) and of the salt [Cp2V(CO)(2)][HB(C6F5)(3)] (5). All were characterized by crystallography. Formation of a hydride vanadium(IV) [(Cp)(C5H4B(C6F5)(3))VH(CO)] obtained by the electrophilic addition of the borane at the Cp-ring followed by redox and disproportionation reaction is suggested to account for these results.