Vanadous acetate

Among other organic compounds of vanadium the following are known Vanadous acetate,8 vanadous acetylacetonate, vanadous benzoyl-acetonatef vanadous carbamides,10 vanadyl acetonates,11 vanadyl acetate,... 

Rearrangement of dehydrolinalool (4) using vanadate catalysts produces citral (5), an intermediate for Vitamin A synthesis as well as an important flavor and fragrance material (37). Isomerization of the dehydrolinalyl acetate (6) in the presence of copper salts in acetic acid followed by saponification of the acetate also gives citral (38,39). Further improvement in the catalyst system has greatly improved the yield to 85—90% (40,41). 

The production of acetic acid from n-butene mixture is a vapor-phase catalytic process. The oxidation reaction occurs at approximately 270°C over a titanium vanadate catalyst. A 70% acetic acid yield has been reported. The major by-products are carbon oxides (25%) and maleic anhydride (3%) ... 

H. 8-Hydroxyquinaldine (XI). The reactions of 8-hydroxyquinaldine are, in general, similar to 8-hydroxyquinoline described under (C) above, but unlike the latter it does not produce an insoluble complex with aluminium. In acetic acid-acetate solution precipitates are formed with bismuth, cadmium, copper, iron(II) and iron(III), chromium, manganese, nickel, silver, zinc, titanium (Ti02 + ), molybdate, tungstate, and vanadate. The same ions are precipitated in ammoniacal solution with the exception of molybdate, tungstate, and vanadate, but with the addition of lead, calcium, strontium, and magnesium aluminium is not precipitated, but tartrate must be added to prevent the separation of aluminium hydroxide. 

Determination of vanadium as silver vanadate Discussion. Vanadates are precipitated by excess of silver nitrate solution in the presence of sodium acetate after boiling, the precipitate consists of silver orthovanadate. The following reactions occur with a solution of a metavanadate ... 

A novel approach was developed very recently by Kita et al. [15]. DKR of allylic alcohols was performed by combining a lipase-catalyzed acylation with a racemization through the formation of allyl vanadate intermediates. Excellent yields and enantioselectivities were obtained. An example is shown in Figure 4.4. A limitation with this approach for the substrates shown in Figure 4.4 is that the allylic alcohol must be equally disubstituted in the allylic position (R = R ) since C—C single bond rotation is required in the tertiary alkoxy intermediate. Alternatively, R or R can be H if the two allylic alcohols formed by migration of the hydroxyl group are enantiomers (e.g. cyclic allylic acetates). 

Geobacter metallireducens is also able to grow by vanadate respiration supported by acetate, and it has been suggested that this could provide a new strategy for removing vanadate from groundwater (Ortiz-Bernad et al. 2004b). 

Anthrapyrimidine and its substituted derivatives are obtained by condensation of 1-aminoanthraquinone (or its derivatives) with formamide or aqueous form-aldehyde/ammonia in the presence of an oxidant, such as ammonium vanadate or m-nitrobenzosulfonic acid. A newly developed, more simple route proceeds via formamidinium chloride, which is prepared from 1-aminoanthraquinone with di-methylformamide and thionyl chloride or phosphorus oxychloride. Cyclization in a solvent in the presence of ammonium acetate affords the desired product ... 

Lithium aluminum hydride reduced )J-azidoethylbenzene to j8-aminoethyl-benzene in 89% yield [600], The azido group was also reduced with aluminum amalgam (yields 71-86%) [149], with titanium trichloride (yields 54-83%) [601], with vanadous chloride (yields 70-95%) [217] Procedure 40, p. 215), with hydrogen sulfide (yield 90%) [247], with sodium hydrosulfite (yield 90%) [259], with hydrogen bromide in acetic acid (yields 84-97%) [232], and with 1,3-propanedithiol (yields 84-100%) [602]. Unsaturated azides were reduced to unsaturated amines with aluminum amalgam [149] and with 1,3-propane-dithiol [602]. 

These salts are made by reducing hot solutions of alkali vanadates with sulphur dioxide after addition of acetic acid they can be salted out by addition of alkali acetate.5 The following are known —... 

With hydrobromic acid and hydriodic acid reduction may proceed to the trivalent state,9 and it has been shown that in the presence of acetic acid, hydrazine also produces vanadous oxide, V203, instead of hypovanadic oxide, V02 10... 

Lead Metavanadate, Pb(VOg)2.—Acid solutions of vanadates on being treated with lead salts give rise to yellow basic vanadates the composition of which varies with the conditions. The precipitation of normal lead vanadate is, therefore, difficult. It has been accomplished by the addition of lead acetate to ammonium metavanadate solution in the presence of acetic acid.2 The lead precipitates contain all the vanadic acid originally present in solution, and precipitation of vanadates with lead salts has, therefore, been employed for the quantitative estimation of vanadium.3 The mineral deschenite consists chiefly of lead metavanadate a portion of the lead is, however, frequently replaced by zinc.4... 

Aminonium Polyvanadates.—The compound (NH4)20.3V205 appears to be the most stable of the arid ammonium vanadates. It is formed by addition of a 10 per cent, solution of acetic acid to a solution of ammonium metavanadate, or by boiling an aqueous solution of any other ammonium polyvanadate. It forms thin, transparent, yellow, octagonal plates, or golden, microscopic, rhombic plates which become temporarily vermilion on being heated, and which are only slightly soluble in water. It has also been obtained combined with two, five, or six molecules of water, according to the temperature of crystallisation or extent of dehydration.2... 

In this case, the slope will be dependent on the number of ligands required for product formation. An example of the application of this equation is provided by the reaction of acetic acid with vanadate, where there is formation of a bisacetato vanadate [9],... 

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