13470-11-6

brownish violet crystal(s); high moisture sensitivity; prepared by reaction of bromine vapor on metallic tungsten at 450°C–500°C [KIR83]

Tungsten(V) bromide, WBr5, consists of an edge-shared bioctahedral structure, with two bridging bromide ligands, so its molecular formula is actually W2Br10. Tungsten(V) bromide is formed by reacting tungsten powder with bromine in between 650℃ and 1000℃. The product is frequently contaminated with tungsten hexabromide.

Tungsten(V) bromide is the precursor to other tungsten compounds by reduction reactions, for example, tungsten(IV) bromide can be prepared by reduction with aluminum or tungsten. WBr4 can be purified by chemical vapor transport.
3WBr5 + Al→3WBr4 +AlBr3