Used as a key reagent in organic synthesis, particularly in Horner-Wadsworth-Emmons (HWE) reactions to form α,β-unsaturated esters and olefins. Its phosphonate group enables selective carbon-carbon bond formation, making it valuable in the preparation of complex molecules such as pharmaceuticals, agrochemicals, and natural products. It is also employed in the synthesis of bioactive compounds where controlled alkene geometry is required. Due to its stability and reactivity, it serves as a versatile building block in medicinal chemistry and materials science.