Vanadyl sulfates

Vanadium(IV) Oxysulfate. Vanadium(IV) oxysulfate pentahydrate (vanadyl sulfate), VOSO4 -5H20) is an ethereal blue sohd and is readily soluble in water. It forms from the reduction of V20 by SO2 in sulfuric acid solution. Vanadium(III) sulfate [13701 -70-7] ) is a powerful... 

Chemical Designations - Synonyms Vanadium oxysuliate. Vanadyl sulfate dihydrate Chemical Formula V0S04 2Hi0. 

Vanadium phthalocyanine (PcVO) is prepared from vanadium(IIl) chloride in a melt of phthalonitrile228 to which sometimes ammonium vanadate137 or molybdate229 and urea are added. Also a reaction with vanadium(V) oxide and phthalonitrile in pen tan-1-ol has been performed.230 Besides these direct syntheses, transformation of PcH2 to PcVO in refluxing dimethylformamide with vanadyl sulfate (V0S04) has been carried out.231... 

It was reported in 1980 that vanadate showed insulin activity (415) at about the same time it was demonstrated that vanadate is reduced to vanadium(IV) in vivo (416,417). Subsequently it was found that orally administered vanadate restored blood glucose levels and cardiac function to normal in rats (418). Vanadyl sulfate, less toxic than vanadate, also lowers blood sugar levels and ameliorates cardiac... 

When sulfur dioxide is passed through a solution of vanadium pentoxide in sulfuric acid, the product is blue crystalline vanadyl sulfate ... 

Elemental composition V 56.02%, O 43.98%. An acid solution is analyzed for vanadium (See Vanadium). Pentoxide in sulfuric acid may he converted to vanadyl sulfate hy reduction with SO2 (See Reactions) or ferrous ammonium sulfate (FAS). The excess FAS may he destroyed with ammonium persulfate. Vanadyl sulfate is then titrated with a standard solution of potassium permanganate ... 

Vanadyl sulfate may be analyzed by titration with a standard solution of potassium permanganate (See Vanadium Pentoxide, Analysis) or any suitable oxidizing agent. An aqueous solution may be analyzed for vanadium by AA or ICP (See Vanadium). 

In a related example, the mixed-valence V2O3 core forms when vanadyl sulfate is oxidized in a pH = 7.5 HCOs /COs buffer. This complex has a reversible oxidation whose potential is pH dependent since the mixed-valence dimer forms by the following equilibrium (Fq. 6) ... 

The [V0(C03)20H] species is apparently the form of vanadyl sulfate present under these conditions and the [V(0)2(C03)2] species is formed from the monomeric V(IV) species by oxidation. Similar processes result in the formation of the V2O3 core when a V(V) source is reduced in the same buffer [101]. 

Research related to the use of vanadium phosphates or V2O5 as oxidants of gases such as CO and SO2 in commercial processes shows that solid vanadyl sulfate can serve as a gas-permeable solid-phase electrolyte [102]. Two reversible redox features are observable at slow scan rates (20-150 mV s ) by CV in a gas-tight two-electrode cell packed with powdered VOSO4 3H2O between a 10-mm carbon disk and a 3-mm glassy carbon electrode. The V(IV/V) couple was observed at 0.55 V versus C, and the V(IV/III) couple was observed at —0.97 V. Unlike in aqueous solution where vanadyl sulfate is reduced to [V(H20)6] ", the V=0 bond in the solid remains intact. The oxidation of CO(g) can be observed when it is introduced into this cell. 

Urea Peroxide Urea Peroxide Hexamethylenetetramine Hexamethylenetetramine Antimony Trioxide Valeraldehyde Valeraldehyde Valeraldehyde Vinyl Acetate Vanadium Pentoxide Vanadyl Sulfate Vanadium Oxytrichloride Vanadium Pentoxide Vanadium Pentoxide Vanadium Oxytrichloride Vanadyl Sulfate Vanadyl Sulfate Vanadium Oxytrichloride Captan... 

Vanadyl Sulfate — Fire Hazards Flash Point (deg. F) Not flammable Flammable Limits in Air (%) Not flammable Fire Extinguishing Agents Not pertinent Fire Extinguishing Agents Not to be l sed Not pertinent Special Hazards of Combustion Products Not pertinent Behavior in Fire No data Ignition Temperature (deg. F) Not pertinent Electrical Hazard Not pertinent Burning Rate Not pertinent. Chemical Reactivity Reactivity with Water No reaction Reactivity with Common... 

Table 23 Anhydrous and Hydrated Forms of Vanadyl Sulfates V0S04mH20 X-Ray Diffraction Data...

Since the approximate charge on vanadium is +1 in the M.O. approximation, a value of the spin orbital coupling constant = 135 cm.-1 is taken for V+.30 The calculation then gives g = 1.983, gll — 1.940, with (g) — 1.969. This is in excellent agreement with the accurately known (g) = 1.962 value for aqueous solutions of VO2, 25-27 The measurements on powdered samples of the vanadyl sulfates also give (g) values in reasonable agreement with this calculation. 

Vanadyl phthalocyanine (7) is effective as a smoke reducer for various styrene polymers.31 Vanadyl sulfate, V0(S04)2, finds application in the production of water resistant polymer foams.32... 

Strehlow, von H., and Wendt, H. (1963). Fast ionic reactions in solution. IV. The formation of the vanadyl sulfate complex in aqueous solution. Inorg. Chem. 2, 6-10. 

They next studied the asymmetric oxidative polymerization of achiral 2,3-dihydroxynaphthalene (Scheme 42). The polymerization of this monomer with CuCl2-(-)-sparteine complex resulted in a low yield and gave a low molecular weight oligomer, whereas the polymerization with CuCl-(S)-Phbox quantitatively gave a polymer with Mn of 10 600-15 300. The enantioselectiv-ity attained in this polymerization, however, was estimated to be low, with 43% ee from the model reaction [169]. When vanadyl sulfate (VOSO -Phbox complex was used instead of the copper catalyst system, the enantioselectivity was improved up to 80% ee [170]. Asymmetric cross-coupling polymerization of two kinds of naphthol derivatives was also reported [171,172]. 

Willsky, G.R., A.B. Goldfine, PJ. Kostyniak, J.H. McNeill, L.Q. Yang, H.R. Khan, and D.C. Crans. 2001. Effect of vanadium(IV) compounds in the treatment of diabetes In vivo and in vitro studies with vanadyl sulfate and bis(maltolato)oxovana-dium(IV). J. Inorg. Biochem. 85 33 12. 

Willsky, G.R., L.-H. Chi, D.P. Gaile, Z. Hu, and D.C. Crans. 2006. Diabetes altered gene expression in rat skeletal muscle corrected by oral administration of vanadyl sulfate. Physiol. Genomics 26 192-201. 

The influences of vanadium compounds on cardiovascular function, a major complication of diabetes, has been reviewed [144], One of the first papers on the antidiabetic effects of oral administration of vanadium compounds (vanadyl sulfate) to rats with STZ-induced diabetes showed improvement of diabetes-impaired cardiac function [122], Recent work has focused on the correction of metabolic defects of diabetes by vanadium and learning more about the immediate mechanism of the antidiabetic effect. The assumption is made that amelioration of the basic metabolic problems of diabetes by vanadium or any other drug will alleviate the long-term complication arising from disease. Diet supplementation with minerals, such as chromium, appears to complement traditional treatments of diabetes to slow the development of complications. Mineral supplementation is believed to be most effective when dietary supplementation is used to correct a deficiency of a mineral [145],... 

Comparison of V(IV,V) hydroxamic acid complexes showed the V(V) complex induced a stronger insulin-enhancing effect than the V(IV) complex, and both complexes were better than either of the salts, vanadyl sulfate or sodium vanadate, in relieving the symptoms of mice with STZ-induced diabetes. The distribution of vanadium in tissues was the same irrespective of the complex administered however, the tissue distribution of vanadium when the salts were administered was different from that seen after vanadium complex administration [146], These results suggest that the difference in the antidiabetic activity of the hydroxaminic acid V complexes is related to the different oxidation state, although there was no difference in the final tissue distribution of these complexes. 

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