“The sale of the product can be completed after your positive verification according to the internal procedure in force in our company. Therefore, this sales proposal is not a binding proposal to conclude a contract until the verification referred to below is positively considered.”
In accordance with Council Regulation (EC) No. 428/2009 of May 5, 2009, as amended amendments establishing the Community export, transfer, brokerage and transit control system for dual-use items, the product is an item of strategic importance and is subject to trade control, including obtaining an export permit and keeping records of trade. Phosphorus trichloride is a colorless, fuming liquid with a pungent, characteristic odor that may resemble that of hydrogen chloride. From a chemical point of view, it is an inorganic acid chloride. Its reaction with water is immediate and very violent, accompanied by a strong exothermic effect and the release of gaseous hydrogen chloride. Therefore, its transport and storage should take place in tightly closed packaging, protected against moisture or flooding. As phosphorus trichloride is highly corrosive, the packaging should be made of a suitable material, preferably steel of specified quality. Its contact with the skin can cause burns, therefore personal protective equipment is important when working with phosphorus trichloride. Due to its high vapor pressure, phosphorus trichloride should also be protected against high temperatures.
Phosphorus trichloride is produced directly from the elements, phosphorus and chlorine, and thanks to the production technology used, it is characterized by high purity, manifested, among others, in very low content of impurities in the form of phosphorus compounds in the fifth oxidation state (i.e. phosphorus oxychloride or PCl5). This is an undeniable advantage and market advantage of this product, especially when it is used for the synthesis of substances with the required very high purity. The low content of elemental sulfur and heavy metals such as arsenic, iron, lead, nickel, chromium and others are also important in this case.
Phosphorus trichloride is most often used as:
- a reagent introducing phosphorus into the substrate molecule through the formation of phosphites, as well as as a result of their subsequent reaction to form, for example, phosphonates (including hydroxyphosphonates and aminophosphonates), which are inhibitors of many enzymes, acting as transition state mimetics;
- chlorinating reagent, used in substitution reactions of hydroxyl groups with a chlorine atom;
- activator in coupling reactions, converting carboxylic or sulfonic/sulfinic acids into their chlorides (more reactive derivatives), coupled with various nucleophiles (e.g. alcohols to form esters or amines to form amides);
- substrate for the synthesis of catalysts, where it serves as a building block for ligands.
- The processes described above are used, among others, for the synthesis of drugs based on sulfonamide derivatives (phosphorus trichloride converts sulfonic acids into amides, e.g. chlorthalidone - a diuretic, sulfadiazine - a bacteriostatic).
Phosphorus trichloride is also a key substrate in the synthesis of bisphosphonates by the method of von Bayer and Hoffmann, which are used as therapeutics for skeletal diseases (e.g. osteoporosis), inhibiting bone resorption and increasing their mass, e.g. alendronate, risedronate, etidronate.