Tungsten(V) chloride, WCl5, is a black solid with a dimeric structure, with a pair of octahedral tungsten(V) centers
bridged by two chloride ligands. The W-W separation is 3.814 ? , which is nonbonding. The compound is isostructural
with Nb2Cl10 and Mo2Cl10. The compound evaporates to give trigonal bipyramidal WCl5 monomers. This compound is analogous in many ways to the more familiar molybdenum pentachloride. It is prepared by reducing WCl6. One method
involves the use of tetrachloroethylene as the reductant.
2WCl6 +C2Cl4→W2Cl10+ C2Cl6
The blue-green solid is volatile under vacuum and slightly soluble in nonpolar solvents. The compound is oxophilic and is very reactive toward Lewis bases.
