Used primarily as a highly reactive sulfonylating agent in organic synthesis, particularly in the development of pharmaceuticals and agrochemicals. Its fluoride group enhances reactivity, making it effective for introducing the 3,4-dichlorobenzenesulfonyl moiety into target molecules. Commonly employed in the preparation of sulfonamide derivatives, which are key structural units in various bioactive compounds. Also utilized in chemical biology for labeling and modifying proteins or peptides due to the selective reactivity of sulfonyl fluorides with nucleophilic amino acid residues like serine and lysine. Shows utility in click chemistry and fragment-based drug discovery owing to its stability under physiological conditions and selective covalent binding.