Used primarily as an intermediate in the synthesis of organophosphorus compounds, including pesticides and flame retardants. It plays a key role in phosphorylation reactions, enabling the formation of phosphate esters and related derivatives. Due to its reactivity, it is also employed in the preparation of chemical warfare agent simulants for research and detection purposes. Its high reactivity with alcohols and amines makes it valuable in organic synthesis for introducing phosphoryl groups. Requires careful handling due to its corrosive and moisture-sensitive nature.