Diethylphosphonobutanoic acid is primarily used in organic synthesis as a versatile intermediate. It plays a significant role in the preparation of phosphonate esters, which are valuable in the development of pharmaceuticals, agrochemicals, and flame retardants. Its application extends to the synthesis of biologically active compounds, where it acts as a key building block for creating molecules with potential therapeutic properties. Additionally, it is utilized in the production of surfactants and corrosion inhibitors, contributing to industrial processes that require specialized chemical formulations. Its phosphonate group makes it particularly useful in chelating metal ions, enhancing its effectiveness in water treatment and detergent formulations.