Used primarily as a sulfonating agent in organic synthesis, enabling the introduction of sulfonyl groups into various substrates. It plays a key role in the preparation of sulfonamides, which are important in pharmaceutical development, particularly in drugs targeting enzyme inhibition or antimicrobial activity. Its reactivity allows for efficient coupling with amines under mild conditions, making it valuable in the construction of complex molecules in medicinal chemistry and agrochemical research. Additionally, it serves as an intermediate in the synthesis of specialty chemicals where sulfonyl functionalities are required for specific reactivity or structural properties.