phosphorus tribromide is used in the manufacture of pharmaceuticals such as alprazolam, methohexital and fenoprofen. It is also a potent fire suppression agent marketed under the name PhostrEx. Phosphorus tribromide is used for doping in microelectronics. Precautions PBr3 evolves corrosive HBr, which is toxic, and reacts violently with water and alcohols. PBr3 + 3 H2O → H3PO3 + 3 HBr In reactions that produce phosphorous acid as a by-product, when working up by distillation be aware that this can decompose above about 160 °C to give phosphine which can cause explosions in contact with air. References Further reading Phosphorus bromides Reagents for organic chemistry Inorganic solvents Fire suppression agents Phosphorus(III) compounds