Vanadium IV chloride

Vanadium IV) chloride, VCI4, b.p. 154 C. Reddish brown liquid formed V plus CI2. Decomposes slowly to VCI3 and CU hydrolysed by water. 

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 (IV) Chloride. Vanadium(IV) chloride (vanadium tetrachloride, VCy is a red-brown hquid, is readily hydrolyzed, forms addition compounds with donor solvents such as pyridine, and is reduced by such molecules to trivalent vanadium compounds. Vanadium tetrachloride dissociates slowly at room temperature and rapidly at higher temperatures, yielding VCl and CI2. Decomposition also is induced catalyticahy and photochemically. This instabihty reflects the difficulty in storing and transporting it for industrial use. 

Vanadium (IV) chloride, removal of, from vanadium (V) oxychloride, 1 107... 

Vanadium(II) chloride is formed when a mixture of vanadium (IV) chloride and hydrogen is passed through a hot tube1 and by the reduction of vanadium(III) chloride with hydrogen.2 It is also produced by the thermal disproportionation of vanadium(III) chloride3,4 into the nonvolatile dichloride and the volatile tetrachloride. 

Vanadium(III) chloride is formed by the decomposition of vanadium(IV) chloride1-4 and by the reaction of vanadium (IV) chloride or vanadium(V) oxychloride with sulfur.3 It may also be produced by the chlorination of vana-dium(III) sulfide,8 by the action of carbon tetrachloride on vanadium (III) oxide6 and of hydrogen chloride on powdered vanadium,2 and by the reaction of liquid chlorine with vanadium metal in a sealed tube.7 The method... 

Thirty milliliters of vanadium (IV) chloride (0.28 mol) is introduced into a 50-ml. round-bottomed flask to which is sealed a small water-cooled condenser (Fig. 13). This operation is carried out in a dry box since the tetrachloride must be protected from contact with moist air. The top of the condenser is sealed to a tube which is connected to a trap cooled with ice. The trap is joined by rubber tubing to a tube containing anhydrous calcium chloride. Dry carbon dioxide is passed through an inlet... 

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] ... 

VANADIUM(IV) CHLORIDE (7632-51-1) VCI4 Decomposes in air and light, forming hydrogen chloride and vanadium pentoxide fumes. Violent decorrrposition in... 

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