Used as a reagent in organic synthesis, particularly for the introduction of sulfonyl groups. It reacts with alcohols to form sulfonate esters, which are good leaving groups in substitution reactions. Also employed in the preparation of sulfonamides by reacting with amines, making it valuable in pharmaceutical synthesis. Its imidazole leaving group enhances reactivity under mild conditions, offering high selectivity. Useful in peptide chemistry and polymer modification due to low toxicity and ease of handling compared to other sulfonylating agents.