A well-defined terminal vanadium(III) oxo complex. Academic Article uri icon

abstract

  • The ubiquity of vanadium oxo complexes in the V+ and IV+ oxidation states has contributed to a comprehensive understanding of their electronic structure and reactivity. However, despite being predicted to be stable by ligand-field theory, the isolation and characterization of a well-defined terminal mononuclear vanadium(III) oxo complex has remained elusive. We present the synthesis and characterization of a unique terminal mononuclear vanadium(III) oxo species supported by the pentadentate polypyridyl ligand 2,6-bis[1,1-bis(2-pyridyl)ethyl]pyridine (PY5Me2). Exposure of [V(II)(NCCH3)(PY5Me2)](2+) (1) to either dioxygen or selected O-atom-transfer reagents yields [V(IV)(O)(PY5Me2)](2+) (2). The metal-centered one-electron reduction of this vanadium(IV) oxo complex furnishes a stable, diamagnetic [V(III)(O)(PY5Me2)](+) (3) species. The vanadium(III) oxo species is unreactive toward H- and O-atom transfer but readily reacts with protons to form a putative vanadium hydroxo complex. Computational results predict that further one-electron reduction of the vanadium(III) oxo species will result in ligand-based reduction, even though pyridine is generally considered to be a poor -accepting ligand. These results have implications for future efforts toward low-valent vanadyl chemistry, particularly with regard to the isolation and study of formal vanadium(II) oxo species.

published proceedings

  • Inorg Chem

author list (cited authors)

  • King, A. E., Nippe, M., Atanasov, M., Chantarojsiri, T., Wray, C. A., Bill, E., ... Chang, C. J.

complete list of authors

  • King, Amanda E||Nippe, Michael||Atanasov, Mihail||Chantarojsiri, Teera||Wray, Curtis A||Bill, Eckhard||Neese, Frank||Long, Jeffrey R||Chang, Christopher J

publication date

  • January 1, 2014 11:11 AM