Used primarily as an intermediate in the synthesis of pharmaceuticals and agrochemicals. Its reactive sulfonyl chloride group enables the formation of sulfonamides, which are key structural motifs in many biologically active compounds. Commonly employed in the development of herbicides and fungicides due to the enhanced stability and lipophilicity imparted by the halogenated aromatic ring. Also utilized in the preparation of dyes and functional polymers where sulfonyl chloride groups act as cross-linking or chain-extension agents. Its halogen substituents allow for further functionalization via cross-coupling reactions, making it valuable in medicinal chemistry for building complex molecules.