Peroxo-complexes of vanadium(V); a vanadium-51 nuclear magnetic resonance study

Abstract

Peroxovanadium(V) species of notional formula [VO(OO)]+, [HVO2(OO)2]2–, [H2VO2(OO)2]–, [VO(OO)3]3–, [HVO(OO)3]2–, [V(OO)4]3–, [H{VO(OO)2}2O]3–, and [VO(NH3)(OO)2]– have been identified in aqueous solution by 51V n.m.r. spectroscopy; species [HVO3(OO)]2–, [VO2(OO)2]3–, and [{V(OH2)(OO)2}2O] are also indicated. The chemical shifts and pKa values indicate that peroxo-ligands bind to vanadium less covalently than oxo-ligands, provided that at least one oxo-ligand remains co-ordinated.