Used as an intermediate in the synthesis of organophosphorus compounds, particularly in the production of pesticides and flame retardants. Serves as a reagent in the Arbuzov and Michaelis–Arbuzov reactions to form phosphonates, which are important in pharmaceuticals and agrochemicals. Employed in the preparation of ligands for catalysts in organic transformations. Also utilized in the formulation of lubricant additives to enhance thermal stability and anti-wear properties.