- Solvothermal synthesis of nanosized particles of vanadium oxide
-
The interaction of vanadyl acetate, vanadium(V) oxide, and vanadium(V) isopropylate with capronic acid has afforded a series of nanosized vanadium oxide powders. The products structure has been studied by X-ray diffraction analysis. Both amorphous and crystalline powders of vanadium oxide can be prepared depending on the starting compound, temperature, and the synthesis duration, the V2O3 (karelianite) structure being in all the cases the most thermodynamically stable. Photocatalytic properties of the prepared powders have been studied.
- Zdravkov,Gorbunova,Koptelova,Khimich
-
-
Read Online
- Synthesis and spectroscopic characterization of mixed ligand complexes of oxovanadium(V)
-
Equimolar reaction of VO(OPri)3 with N-phenyldiethanolamine affords [VO(L)(μ-OPri)]2 (1), which reacts with a variety of mono- and bi-dentate ligands such as MeOH, EtOH, MeOCH2CH2OH, MeNHCH2CH2OH, Me 3CCH2OH, Me3COH, EtCMe2OH, and C10H7N=CHC6H4OH (where C 10H7 represents napthyl group) yielding the dimeric [VO(L)(μ-OMe)]2(2), [VO(L)(μ-OEt)]2(3), [VO(L)(μ-OCH2CH2OMe)]2(4), [VO(L)(μ-OCH2CH2NHMe)]2(5), [VO(L)(μ-OCH2CMe3)]2(6), [VO(L)(μ-OCMe3)]2(7), [VO(L)-(μ-OCMe 2Et]2(8), and the monomeric complexes, [VO(L)(OC 6H4CHNC10H7)](9), respectively. A detailed study of alcoholysis reactions of VO(L)(OPri) with a number of monofunctional alcohols indicates the following order of reactivity: OMe > OEt ≈ OCH2CH2OMe ≈ OCH2CH 2NHMe > OCH2CMe3 > OCMe3 > OCMe2Et. All of these complexes have been characterized by elemental analyses, molecular weight measurements and spectroscopic (IR, 1H and 51V NMR) studies, on the basis of which plausible structures have been suggested for the novel complexes.
- Ghadwal, Rajendra Singh,Singh, Anirudh
-
p. 2644 - 2649
(2007/10/03)
-
- Functionalized Oxovanadium Alkoxides - Potential Haptens
-
Several new oxovanadium alkoxides and alkoxides/chlorides of the composition VOCl3-n(OR)n (n = CPh3; n = 2 and 3, R = CPh3, iBu, cyclopentyl, tert-pentyl, octyl; n 3, R = dodecyl, 3-methylbutyl) and the mixed ester VO(OiBu)-(OCPh3)2 have been prepared.The compounds VO(OiBu)2OR' have ben synthesized, where R' is a functionalized long-chain alkyl group .The chloride/carboxylate VOCl2 has also been obtained.The compounds are characterized, inter alia, by 51V-NMR spectroscopy.Typical 51V shift ranges are observed for specific ligand functionalities (chlorides, alkoxide, carboxylate). δ(51V) values also depend on the steric requirement of the groups R and the coordination number.The importance of the functionalized esters as potential triggers for the production of abzymes with phosphatase activity is discussed.Key Words: Vanadium Alkoxides / Haptens / NMR, 51V
- Hillerns, Frank,Rehder, Dieter
-
p. 2249 - 2254
(2007/10/02)
-
- Preparation and 51V NMR characteristics of oxovanadium(V) compounds. Relation between metal shielding and ligand electronegativity
-
The light-sensitive vanadyl compounds VOCl2(O-t-Bu), VOCl3-n(NEt2)n and VOF3-n(O-i-Pr)n (n = 1, 2), VO(S-i-Pr)(O-i-Pr)2, and VOCl3·xNHEt2 have been prepared and investigated. Mixtures of VOCl3-n(O-i-Pr)n and LiNEt2 are shown to generate multicomponent systems containing, inter alia, VO(NEt2)(O-i-Pr)2, VO(NEt2)2(O-i-Pr), and Li[VO(NEt2)(O-i-Pr)3]. Solutions of VOCl3, VOF3, or VOCl3/VOF3 in THF likely contain associated species composed of {VOX3(X′)-} subunits with one of the substituents (X′) labilized and interchangeable. 1J(51V-14N) coupling constants have been observed for VO(NEt2)Z2 (1/1/1 triplets: Z = Cl, 55 Hz; Z = O-i-Pr, 110 Hz) and [VO(NEt2)(O-i-Pr)3]- (116 Hz) and 1J(51V-19F) has been found for VOF3/Me2SO (binominal quintet; 85 Hz). Linear progressions exist between δ(51V) and substituent (Z) parameters such as the electronegativity χ, Pearson's hardness parameter, and Taft's electronic and steric constants for both the [VOF40-nCln]- and VOZ3 series. The shielding/χ correlations are rationalized on the basis of recently reported PE spectra and SCF-Xα calculations on VOCl3 and VOF3.
- Priebsch, Wolfgang,Rehder, Dieter
-
p. 3058 - 3062
(2008/10/08)
-
