Tungsten V Trichloride Oxide

After about 40 hours the reaction is complete, and the tube is placed immediately in a reverse temperature gradient of 200°C./ room temperature in order to separate the more volatile species from the desired product. The preparation of tungsten(V) trichloride oxide, first reported by Fowles and Frost,4,s is very dependent on the amount of excess tungsten(VI) chloride and the temperature gradient used. Employing the above conditions, 15.2 g. of tungsten(V) trichloride oxide (83% yield) was obtained. 

It has been determined by differential thermal analyses (D.T.A.) that tungsten(V) trichloride oxide decomposes above 290°C. without a sharp transition point. On cooling, a transition is observed at 210°C., the melting point of tungsten(VI) tetrachloride oxide. Therefore the decomposition of tungsten(V) trichloride oxide seems to take place by the following reaction ... 

HYDRAZONE, OXIMES Molybdenum(V) trichloride oxide. Tungsten hexafluoride. 

Tungsten(VI) oxide tetrachloride is a common impurity in tungsten(VI) chloride. By anaiogy with niobium(V) oxide trichloride (Section 9.2.2), phosgene might have been expected to convert WOCi to WClj, according to ... 

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