fosforikloridin

Phosphorus oxychloride, POCl3, also known as fosforikloridin in some languages, is a colorless to faintly yellow, highly reactive liquid. It is moisture‑sensitive and fumes in air. Its primary role is as a chlorinating and dehydrating reagent in organic synthesis, enabling phosphorylation and related transformations.

In contact with water, POCl3 hydrolyzes rapidly to phosphoric acid and hydrogen chloride: POCl3 + 3 H2O → H3PO4 + 3 HCl. It reactively interacts with alcohols, phenols, and amines to form phosphate esters and other phosphorylating reagents. It is commonly used to convert alcohols to alkyl phosphates and to prepare reactive phosphorylating agents. In the Vilsmeier–Haack reaction, POCl3 reacts with dimethylformamide (DMF) to generate a formylating reagent used to introduce formyl groups into aromatic and heteroaromatic rings.

Industrial and laboratory applications encompass its role as a key intermediate in the synthesis of organophosphorus compounds, including flame retardants, plasticizers, and various agrochemical precursors. It is also employed in polymer chemistry and in the preparation of phosphate esters for diverse applications.

Safety handling requires noting that POCl3 is highly corrosive and toxic by inhalation and skin contact. It reacts violently with water, releasing heat and corrosive hydrogen chloride. It should be handled in a dry, well‑ventilated fume hood, with appropriate protective equipment. Containers must be tightly closed and kept away from moisture; waste handling must follow applicable regulations due to its corrosive and hazardous nature.