Used primarily as a building block in organic synthesis, especially in pharmaceutical and agrochemical industries. Its conjugated system and ester functionality make it suitable for Michael additions, Diels-Alder reactions, and other cycloadditions. Commonly employed in the preparation of substituted cyclopentanes and cyclopentenones, which are key motifs in natural products and bioactive molecules. Also utilized in polymer chemistry as a reactive monomer for specialty copolymers with unique thermal or mechanical properties.