Dinuclear fluoro-peroxovanadium(v) complexes with symmetric and asymmetric peroxo bridges: syntheses, structures and DFT studies

Abstract

Two new dinuclear fluoro peroxovanadium(v) complexes, Cs3[V2O2(O2)4F] x H2O (1) and Cs3[V2O2(O2)3F3] x 2HF x H2O (2), were prepared and characterized by elemental analysis, IR spectroscopy, thermal analysis and X-ray crystallography. While the anion in possesses an asymmetric structure with a micro-eta1:eta2 bridging peroxo group, the [V2O2(O2)3F3]3- ion in exhibits a symmetrical structure with a unique mu-fluoro and micro-eta2:eta2 peroxo double bridge. The X-ray structure data were compared with equilibrium and vibrationally-averaged (effective) DFT calculated geometries. The decomposition reactions of and in aqueous solution were studied by 51V NMR spectroscopy. The calculations of vibrationally averaged NMR chemical shifts (DFT-GIAO) were used to support the empirical assignment of NMR signals and afforded excellent agreement with experimental values for the studied peroxovanadium species. The ESI mass spectra of the prepared compounds are in accordance with the assignment of NMR spectra and with DFT study.

Vanadium and molybdenum peroxides: synthesis and catalytic activity in oxidation reactions

“…43 When the more complex bimetallic species 37 and 38 are dissolved in water, [VO(O 2 ) 2 (H 2 O)]and [VO(O 2 ) 2 F] 2have been detected as the most important species. 47 The formation of fluoro diperoxo vanadium anion, from vanadate and hydrogen peroxide, has been observed in a waterhydrophilic ionic liquid (bmimBF 4 ) mixture. 62 Remaining in the field of speciation in aqueous peroxovanadateligands systems, some bio-related works have been published by Salifoglou and colleagues 32-34,48,55, 63 The papers refer to the quite complex equilibria that are taking place in water at physiological conditions, between vanadium and biogenic ligands such as citrate or glycine.…”

Structural and spectral properties of tartrato complexes of vanadium(V) from quantum chemical calculations

“…Wachters+f set is frequently used for first-row transition metals. It proved to perform fairly well in calculations for complexes of vanadium, too [19,[28][29][30]. In order to improve the description of the donoracceptor bond between the central and the donor atom, inclusion of f functions on the central atom is, however, fully appropriate.…”

Vanadium, niobium and tantalum

“…7 The structure of dinuclear fluoro peroxovanadium(V) complexes [{Cs 3 }{V 2 O 2 (O 2 ) 4 F}ÁH 2 O] and [{Cs 3 }{V 2 O 2 (O 2 ) 3 F 3 }ÁH 2 O] was examined both experimentally as well as computationally. 8 The unsymmetrical, chiral, mixed-valent, triply bridged, dinuclear vanadium(IV/V) complexes [(3,5-Me2pzH)-OV(m-acac)(m-O)(m-O 2 CCH 3 )VO(acac)] was generated. 9 A series of scorpionate, Tp-based oxovanadium(IV)-carboxylate complexes was synthesised.…”