Tungsten oxychlorides

Long et al. reported the synthesis of tungsten oxychloride clusters via a soft-chemistry route [60], which confirms the potential for wide applications of the ligand combination strategy in cluster chemistry. 

TABLE 1. Polymerization Reaction Scoping for Preparation of Polycyclopentadiene Using Tungsten Oxychloride as Catalyst and Corresponding Physical Properties... 

Curable poly(dicyclopentadiene), (V), was prepared by Konze et al. (4) using ring-opening metathesis polymerization with tungsten oxychloride and diallyldimethylsilane. 

Similar reactivity is seen for the tungsten oxychloride (equation 56)84,85 and for oxomolybdenum complexes (equation 57).46... 

Tungsten oxytetrachlofide [13520-78-0], WOCl, mp 211°C, bp 221°(Z, is a red crystalline soHd. It is soluble in carbon disulfide and ben2ene and is decomposed to tungstic acid by water. It may be prepared by refluxing sulfurous oxychloride, SOCI2, on tungsten trioxide (12) and purified after evaporation by sublimation. 

VI. Reactions of difluorodithiophosphinic acid with chlorides and oxychlorides of chromium, molybdenum and tungsten. Inorg. Chem. 11, 2011 (1972). 

Often at high temperatures the reaction product is an oxychloride, particularly when the reactant is an oxide of a heavy transition metal, such as, halhi-um or tungsten. 

Fill the apparatus with chlorine and perform chlorination of the molybdenum, heating the place of the tube where the metal is with the flame of a burner to 200-300 °C. What colour do molybdenum pentachloride and tungsten hexachloride have If oxychlorides are produced together with the molybdenum(V) or tungsten(VI) chlorides, distil them off in a chlorine stream. Transfer the product into a weighed test tube with a stopper, weigh it, and hand it in to your instructor. Calculate the yield in per cent. 

In this method metal chlorides or oxychlorides are made to react with gaseous hydrocarbons in the vicinity of a localized heat source (1400-2100 K). Clearly, the reaction is thermodynamically favorable (Tables 3 and 4). The method was first used by Van Arkel in 1923 with an incandescent tungsten filament to make carbides of tantalum and zirconium [40]. Although the reaction variables have been studied extensively, problems remain with control of the process and with low productivity. Application to catalyst synthesis has been moderate [41],... 

Element 106. The chemical properties of element 106 (eka-tungsten) are predicted to be similar to those of tungsten, molybdenum and to some extent chromium, offering an even richer chemistry of complex ions than these elements. The hexafluoride should be quite volatile and the hexachloride, pentachloride and oxychloride should be moderately volatile. Penneman and Mann predict a -)-4 oxidation state in aqueous solution. Jprgensen s selection of k is for the hydrated cation and is not intended to account for the effects of complex ion formation. However, since tungsten is stabilized in the oxidation state of -t-6 by the tungstate ion, an analogous situation may be expected for element 106. 

Oxychlorides.—Two oxychlorides of tungsten, respectively WO2CI2 and WOCI4, are known. 

Tungsten oxytetrachloride forms splendid transparent, ruby-red, needle-shaped crystals which melt at 210° C. and boil at 227-5° C., giving a red vapour of normal density. - By water it is decomposed, giving first the yellow oxychloride, and further, hydrochloric and tungstic acids. A certain amount of the yellow oxychloride is also formed from it by loss of chlorine on sublimation in air or oxygen. ... 

The trioxide remains unchanged when heated in a current of nitric oxide it is reduced to lower oxides by ethylene or acetylene at red heat, by methane at a higher temperature, and by phosphine at 125° to 150° C. Heated with phosphorus pentachloride in an atmosphere of carbon dioxide it yields a red-brown product which consists of a mixture of tungsten chlorides and oxychlorides. ... 

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