Tungsten dichloride dioxide 5439480 183961959 2008-01-13T02:27:37Z Chem-awb 4806773 chemicals pages cleanup per [[User:Beetstra/Chemicals]] using [[Project:AutoWikiBrowser|AWB]] {{Chembox new | Name = Tungsten(VI) dioxydichloride | ImageFile = WO2Cl2.png <!-- | ImageSize = 150px --> | ImageName = Tungsten(VI) dioxydichloride | OtherNames = tungsten(VI) dioxydichloride | Section1 = {{Chembox Identifiers | CASNo = 13520-76-8 }} | Section2 = {{Chembox Properties | Formula = WO<sub>2</sub>Cl<sub>2</sub> | MolarMass = 286.75 g/mol | Appearance = yellow crystals | Density = 4.67 g/cm<sup>3</sup>, solid | MeltingPt = 265 °C | BoilingPt = sublimes > 350 °C in vacuo | Solubility = decomposes }} | Section3 = {{Chembox Structure | CrystalStruct = orthorhombic }} | Section7 = {{Chembox Hazards | EUClass = not listed }} }} '''Tungsten dichloride dioxide''' is the [[chemical compound]] with the formula [[Tungsten|W]][[Oxygen|O<sub>2</sub>]][[Chlorine|Cl<sub>2</sub>]]. This yellow-colored solid is used as a precursor to other tungsten compounds. Like other tungsten halides, WO<sub>2</sub>Cl<sub>2</sub> is sensitive to moisture, ungoing hydrolysis. ==Preparation== WO<sub>2</sub>Cl<sub>2</sub> is prepared by ligand redistribution reaction: : 2 [[tungsten trioxide|WO<sub>3</sub>]] + [[tungsten hexachloride|WCl<sub>6</sub>]] &rarr; 3 WO<sub>2</sub>Cl<sub>2</sub> Using a two-zone furnace, a vacuum-sealed tube containing these solids is heated to 350 C. The yellow product sublimes to the cooler end of the reaction tube. No redox occurs in this process.<ref>Tillack, J. "Tungsten Oxyhalides" Inorganic Syntheses, 1973, XIV, 109-122. ISBN 0-07-071320-0.</ref> An alternative route highlights the "oxophilicity" of tungsten:<ref>Gibson, V. C.; Kee, T. P.; Shaw, A. "New, improved synthesis of the group 6 oxyhalides, W(O)Cl<sub>4</sub>, W(O)<sub>2</sub>Cl<sub>2</sub> and Mo(O)<sub>2</sub>Cl<sub>2</sub>" Polyhedron 1988, volume 7, pages 579-80.</ref> :WCl<sub>6</sub> + 2 O(Si(CH<sub>3</sub>)<sub>3</sub>)<sub>2</sub> &rarr; 3 WO<sub>2</sub>Cl<sub>2</sub> + 4 ClSi(CH<sub>3</sub>)<sub>3</sub> This reaction, like the preceding one, proceeds via the intermediacy of W(O)Cl<sub>4</sub>. ==Other tungsten oxy chlorides== Tungsten forms a number of oxyhalides including WOCl<sub>4</sub>, WOCl<sub>3</sub>, WOCl<sub>2</sub>. The corresponding bromides are also known as is WO<sub>2</sub>I<sub>2</sub>.<ref>Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.</ref> ==Reactions== WO<sub>2</sub>Cl<sub>2</sub> is a [[Lewis acid]], forming soluble adducts of the type WO<sub>2</sub>Cl<sub>2</sub>L<sub>2</sub>, where L is a donor ligand such as [[bipy]]. ==References== {{reflist}} [[Category:Oxides]] [[Category:Chlorides]] [[Category:Tungsten compounds]] [[Category:Inorganic compound stubs]] {{inorganic-compound-stub}} [[ar:ثنائي كلوريد ثنائي أكسيد تنغستن سداسي]]