The preparation and properties of CpVBr3 and CpVI3 (Cp = η5-C5H5) are described. The compound CpVBr3 exhibits an E1/2 of 510 mV (vs Ag/AgCl) and is able to oxidize ferrocene. The salt [Cp2Fe][CpVBr3] was characterized by infrared spectroscopy (vCH(Cp2Fe) = 857 cm-1), 57Fe Mössbauer spectroscopy at 295 K (δ1 = 0.35, δ2 = 0-421 mm/s) and 150 K, variable-temperature magnetic susceptibility (μeff(300 K) = 3.75 μB), and 1H NMR spectroscopy. While CpVBr3 is more oxidizing than CpVCl3, we find that CpVI3 is less oxidizing (E1/2 = 425 mV). In solution CpVI3 exists as two distinct species as shown by 1H NMR spectroscopy. The structure of CpVI3 was solved in the orthorhombic space group Pn21a (no. 33, alternate setting) with the lattice constants a = 11.847 (4) Å, b = 11.304 (3) Å, c = 7.532 (1) Å, and Z = 4.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Inorganic Chemistry