Used as a key intermediate in organic synthesis, particularly in the preparation of sulfonamide-based pharmaceuticals. It serves as a sulfonylating agent, enabling the introduction of the 4-bromobenzenesulfonyl group to amines and other nucleophiles. The presence of the bromine atom allows for further functionalization via cross-coupling reactions, such as Suzuki or Heck couplings, making it valuable in medicinal chemistry for building complex molecules. It is also employed in the development of protease inhibitors and other biologically active compounds where sulfonyl fluoride groups act as enzyme inhibitors. Additionally, it is used as a chemical probe for studying proteins and enzymes, reacting specifically with residues such as cysteine, serine, or tyrosine. Its reactivity and versatility support its use in both solution-phase and solid-phase synthesis, as well as in biochemical research.