Vanadium oxide chlorid

Vanadium oxide chloride Cyclodehydrogenation Oxidative coupling of phenols... 

Chlorine is readily soluble in sulfiir-chlorine compounds, which can be used as industrial solvents for chlorine. Disulfiir dichloride U0025-67-9], S2CI2, is converted to sulfur dichloride (SCI2) and sulfiir tetrachloride (SCI4). Some metallic chlorides and oxide chlorides, such as vanadium oxide chloride, chromyl chloride, titanium tetrachloride, and tin(IV) chloride, are good solvents for chlorine. Many other chlorine-containing compounds dissolve chlorine readily. Examples are phosphoryl chloride, carbon tetrachloride (Fig. 7), tetrachloroethane, pentachloroethane, hexachlorobutadiene... 

Vanadium oxide chloride Oxidative coupling of phenols Morphinane ring closure with subsequent isocyclic ring opening... 

Vanadium oxide trichloride, VOCI3, vanadyl chloride. Readily prepared yellow liquid, b.p. 127 C, formed CK plus heated V2OS plus C. Readily hydrolysed by water. 

Vanadium metal can be prepared either by the reduction of vanadium chloride with hydrogen or magnesium or by the reduction of vanadium oxide with calcium, aluminum, or carbon. The oldest and most commonly used method for producing vanadium metal on a commercial scale is the reduction of V20 with calcium. Recently, a two-step process involving the alurninotherniic reduction of vanadium oxide combined with electron-beam melting has been developed. This method makes possible the production of a purer grade of vanadium metal, ie, of the quaUty required for nuclear reactors (qv). 

Some properties of selected vanadium compounds are Hsted in Table 1. Detailed solubiUty data are available (3), as are physical constants of other vanadium compounds (4). Included are the lattice energy of several metavanadates and the magnetic susceptibiUty of vanadium bromides, chlorides, fluorides, oxides, and sulfides (5). 

Vanadium, a typical transition element, displays weU-cliaractetized valence states of 2—5 in solid compounds and in solutions. Valence states of —1 and 0 may occur in solid compounds, eg, the carbonyl and certain complexes. In oxidation state 5, vanadium is diamagnetic and forms colorless, pale yeUow, or red compounds. In lower oxidation states, the presence of one or more 3d electrons, usually unpaired, results in paramagnetic and colored compounds. All compounds of vanadium having unpaired electrons are colored, but because the absorption spectra may be complex, a specific color does not necessarily correspond to a particular oxidation state. As an illustration, vanadium(IV) oxy salts are generally blue, whereas vanadium(IV) chloride is deep red. Differences over the valence range of 2—5 are shown in Table 2. The stmcture of vanadium compounds has been discussed (6,7). 

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... 

Vanadium oxide as catalyst, 174 Vinyl chloride, manufacture of, using catalysts, 238... 

Vanadium compounds in a low oxidation state are known to be effective for inducing one-electron reduction. The highly stereoselective monodebromination of gem-dibromocyclopropanes proceeds with the help of a low-valent vanadium species generated from vanadium(III) chloride and zinc in dimethoxyethane in cooperation with diethyl phosphonate or triethyl phosphite... 

The reactions of the vanadium oxide cluster cations with CCI4 were of three types (248). The small cluster ions reacted by transfer of a chloride ion. The larger clusters starting with the V4OJ+ series reacted by the addition of a chlorine atom to the cluster or the loss of one oxygen atom and the addition of two chlorine atoms. 

The ability of vanadium(II) chloride to facilitate sulfoxide deoxygenation has been discussed (Section IV,C), and it appears that vana-dium(III) sulfoxide complexes may be prepared by air oxidation of van-adium(II) salts in the presence of the sulfoxide. In this manner, [V(Me2S0)6][C104]3 was prepared from vanadium(II) perchlorate (119) and the kinetics of substitution with thiocyanate ion detailed. Care is necessary in handling the pure compound, as it is reported to be sensitive to detonation. A large number of oxovanadium(IV) species have... 

Demet X procedure simply consists of an oxidation at elevated temperature, both the New Demet and the Demet III process has a sulfiding step which transforms the metal oxides to insoluble sulfides. In Demet III the sulfiding step is followed by a partial oxidation step. This oxidation is carefully controlled to produce metal sulfates and sulfides which can be directly removed by washing or be transferred into soluble compounds by the reductive and oxidative washes used in this procedure. In the New Demet process the sulfiding step is followed by chlorination which results in a transformation of the sulfides into washable chlorides. Since vanadium chlorides are volatile, most of the vanadium removal using this procedure occurs in the gas phase. In the Demet X procedure, the vanadium oxides formed are water soluble or can be transformed into water soluble forms by aqueous treatments. In contrast the nickel oxides are insoluble in water. 

An interesting oxidative decarboxylation process was reported for a /(-hydroxy acid. Reaction of 2-ethyl-2-(l -hydroxycyclobutyl)butanoic acid with vanadium(III) chloride in the presence of 1 equivalent of l,8-bis(dimethylamino)naphthalcne (Proton Sponge) gave 3-cyclobutylidene-pentane (20).181... 

Lockyer and Baxcndall1 investigated the arc spectrum of vanadium by volatilising vanadium chloride and vanadium oxide between poles of pure silver. Using a Rowland grating, over 650 lines were obtained in the region between A 3887 and A 4932, the more intense of which arc indicated in the following table —... 

Oxidation, Ammoxidation, and Oxychlorination Numerous catalysts have been developed for a number of processes in this category. Examples arc supported vanadium oxide, complex muitimetallic oxides, and supported cupric chloride, used respectively for the following reactions ... 

Oxidative dehydrogenation of alcohols is a new approach in the development of industrial processes for the synthesis of aldehydes and ketones [103-105], In this regard, the technologically most suitable is the method of acetaldehyde synthesis in the presence of melted vanadium oxide, alkaline metals with promoting additives, alkaline metal sulfates or chlorides as catalysts [105], The target product yield equals 65.9% per used alcohol at 69.2% conversion. The disadvantage of the method is the relatively low yield of the target product... 

Vanadium, powder by reduction of oxide with calcium, 6 50 Vanadium(II) chloride, 4 126 Vanadium (III) chloride, 4 128 6-hydrate, 4 130... 

Vanadium(II) chloride forms apple-green leaflets which behave toward water somewhat like chromium (II) chloride.5 They may be wetted slowly by water. The salt is soluble in water, forming the violet hydrated vanadium(II) ion. This ion is readily oxidized by the oxygen of the air and by hydrogen ion. The salt dissolves in alcohol and ether, the resulting solutions being respectively blue and greenish yellow.3... 

To overcome the problems encountered in the homogeneous Wacker oxidation of higher alkenes several attempts have been undertaken to develop a gas-phase version of the process. The first heterogeneous catalysts were prepared by the deposition of palladium chloride and copper chloride on support materials, such as zeolite Y [2,3] or active carbon [4]. However, these catalysts all suffered from rapid deactivation. Other authors applied other redox components such as vanadium pentoxide [5,6] or p-benzoquinone [7]. The best results have been achieved with catalysts based on palladium salts deposited on a monolayer of vanadium oxide spread out over a high surface area support material, such as y-alumina [8]. Van der Heide showed that with catalysts consisting of H2PdCU deposited on a monolayer vanadium oxide supported on y-alumina, ethene as well as 1-butene and styrene... 

Dichlorotetrakis(2-propanol) vanadium (III) chloride forms bright green crystals which are readily hydrolyzed and oxidized. Indeed, the coordinated alcohol molecules are readily displaced by most other ligands. In solution the band reported at 21,300 cm.-1 disappears after only a few hours even in a stoppered cell, and so all spectra must be taken in a sealed coll.4 Conductivity... 

Other catalysts effective in the conversion of isocyanates into carbodiimides include the naphthenates of Mn, Fe, Co, Cu and Pb, derivatives of metallic acetylacetonates, the alkoxides of titanium, zirconium and niobium and vanadium oxides or chlorides. Sterically hindered isocyanates are readily converted into carbodiimides upon heating in the presence of a catalytic amount of a strong base. For example, heating of... 

VANADIUM BROMIDE see VEKOOO VANADIUM CHLORIDE see VEFOOO VANADIUM(III) CHLORIDE see VEPOOO VANADIUM COMPOUNDS see VCZOOO VANADIUM DUST and FUME (ACGIH) see VDUOOO VANADIUM DUST and FUME (ACGIH) see VDZOOO VANADIUM (OSHA) see VDZOOO VANADIUM OXIDE see VEAOOO VANADIUM(V) OXIDE see VDUOOO VANADIUM OXYTRICHLORIDE see VDPOOO VANADIUM PENTAOXIDE see VDUOOO VANADIUMPENTOXID (GERMAN) see VDUOOO VANADIUM PENTOXIDE (dust) see VDUOOO VANADIUM PENTOXIDE (fume) see VDZOOO... 

The ability of phosphines to act as both a metal oxidation states and as a 7r acceptor to relieve electron density from lower metal oxidation states explains, in part, the observation that diphosphines stabilize the +3, +1, and 0 oxidation states at the expense of the +2 oxidation state.870 Vanadium(II) diphosphine halides, [V(dmpe)2X2] (dmpe = dimethyl-dimethylphosphinoethane, X = Br or I), were prepared as side products in the synthesis of [XV(CO)2(dmpe)2].885 The structurally characterized diphosphino V11 tetrahydroborate complex, tra .s-[V(BH4)2(dmpe)2], (223) was synthesized via the reduction of similar vanadium(III) precursors.832 The reaction of a vanadium(II) chloride salt with dmpe afforded the tra s-[VCl2(dmpe)2] complex which can be alkylated with MeLi or MgMe2 to afford the organometallic trans-[V(Me)2(dm pcVJ compound, which in turn reacts with thiocyanate to form tnms -[V(NCS)2(dmpe)2].8 87 Acetonitrile or propionitrile readily displace the chlorides from trans- WCl2(dmpe)2] to form // tf/ ,v-[V( NCR)2(dmpc)2][BI>h4]2 (R = Me or Et) the acetonitrile derivative reacts with HCPh(S02CF3)2 in acetonitrile solvent to yield the hexaacetonitrile species [V(NCMe)6]2+.887... 

Valeric Acid 11099-11-9 Vanadium Oxide 112-52-7 Lauryl Chloride... 

Vanadium(V) oxide is reported to react with phosgene at 350 C to give vanadium(IV) chloride, whereas tantalum(V) oxide reacts with phosgene to give tantalum(V) chloride [360] ... 

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