ABSTRACT
Phosphorus oxychloride is the mixed anhydride of phosphoric and hydrochloric acids, a corrosive liquid (bp 107°C) that fumes in moist air. In contact with cold water, it initially collects in a dense immiscible layer. However, after a short delay, a very vigorous reaction commences, accelerated by its exothermicity, producing phosphoric and hydrochloric acids. Its vapors are lachrymatory and poisonous, with a possible latent physiological action [2] similar to that of phosgene, with which it shares a structural and functional similarity. Hence, phosphorus oxychloride is a sea-freight item. Industrially, phosphorus oxychloride is manufactured by either the oxidation of PCl3 with oxygen, or with chlorine in the presence of P2O5. Laboratory methods rely on either the partial hydrolysis of PCl5, or the reaction between P2O5 and PCl5 [1,2]. Because phosphorus chlorides are themselves sea-freight items, two preparations from easily available chemicals are presented here.
