Tungsten dichloride dioxide, or Tungstyl chloride is the

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

with the formula W O₂ Cl₂. It is a yellow-colored solid. It is used as a precursor to other tungsten compounds. Like other tungsten halides, WO₂Cl₂ is sensitive to moisture, undergoing hydrolysis.

Preparation

WO₂Cl₂ is prepared by ligand redistribution reaction from

tungsten trioxide Tungsten(VI) oxide, also known as tungsten trioxide is a chemical compound of oxygen and the transition metal tungsten, with formula WO3. The compound is also called tungstic anhydride, reflecting its relation to tungstic acid . It is a light ...

and tungsten hexachloride: : 2 WO₃ + WCl₆ → 3 WO₂Cl₂ Using a two-zone

tube furnace A tube furnace is an electric heating device used to conduct syntheses and purifications of inorganic compounds and occasionally in organic synthesis. One possible design consists of a cylindrical cavity surrounded by heating coils that are embe ...

, 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. An alternative route highlights the

oxophilicity Oxophilicity is the tendency of certain chemical compounds to form oxides by hydrolysis or abstraction of an oxygen atom from another molecule, often from organic compounds. The term is often used to describe metal centers, commonly the early trans ...

of tungsten: :WCl₆ + 2 O(Si(CH₃)₃)₂ → 3 WO₂Cl₂ + 4 ClSi(CH₃)₃ This reaction, like the preceding one, proceeds via the intermediacy of WOCl₄.

Structure

The compound is a polymer consisting of distorted octahedral W centres. The monomer is characterized by two short W-O distances, typical for a multiple W-O bond, and two long W-O distances more typical of a single or dative W-O bond.

Related oxy halides

Tungsten forms a number of

oxyhalide In chemistry, molecular oxohalides (oxyhalides) are a group of chemical compounds in which both oxygen and halogen atoms are attached to another chemical element A in a single molecule. They have the general formula , where X = fluorine (F), chlor ...

s including WOCl₄, WOCl₃, WOCl₂. The corresponding bromides (WOBr₄, WOBr₃, WOBr₂) are also known as is WO₂I₂.

Reactions

WO₂Cl₂ is a Lewis acid, forming soluble adducts of the type WO₂Cl₂L₂, where L is a donor ligand such as

bipyridine Bipyridines also known as bipyridyls, dipyridyls, and dipyridines, are a family of chemical compounds with the formula (C5H4N)2, consisting of two pyridyl (C5H4N) rings. Pyridine is an aromatic nitrogen-containing heterocycle. Bipyridines are of si ...

and

dimethoxyethane Dimethoxyethane, also known as glyme, monoglyme, dimethyl glycol, ethylene glycol dimethyl ether, dimethyl cellosolve, and DME, is a colorless, aprotic, and liquid ether that is used as a solvent, especially in batteries. Dimethoxyethane is mi ...

. Such complexes often cannot be prepared by depolymerization of the inorganic solid, but are generated in situ from WOCl₄.K. Dreisch, C. Andersson, C. Stalhandske "Synthesis and structure of dimethoxyethane-dichlorodioxo-tungsten(VI)—a highly soluble derivative of tungsten dioxodichloride" Polyhedron 1991, volume 10, p. 2417.

References

Tungsten compounds Oxychlorides {{Inorganic-compound-stub