Used primarily as an intermediate in the synthesis of pharmaceuticals and agrochemicals. It serves as a building block in the preparation of sulfonamide derivatives, which are important in the development of antimicrobial and anti-inflammatory agents. Its reactivity allows for easy introduction of the 4-(4-chlorophenyl)phenylsulfonyl group into target molecules, enhancing structural diversity in drug discovery. Also employed in the production of dyes and functional materials where sulfonyl chloride groups enable covalent attachment to other molecular frameworks.