Used primarily as a reagent in organic synthesis, particularly for introducing the sulfonyl group into molecules. It is commonly employed to convert alcohols into sulfonate esters, which are good leaving groups in nucleophilic substitution reactions. Widely used in the preparation of pharmaceuticals, agrochemicals, and dyes due to its ability to modify functional groups and enhance reaction pathways. Also serves as a protecting group agent for amines and alcohols in multi-step syntheses. Its reactivity makes it valuable in peptide synthesis and in the production of sulfonamide-based compounds, which are key in medicinal chemistry.