Used as a key reagent in organic synthesis, particularly in the preparation of sulfonate esters and sulfonamides. It acts as a sulfonylating agent, enabling the introduction of mesitylene-based sulfonyl groups into various substrates. This is valuable in pharmaceutical development for modifying drug molecules to improve stability or alter reactivity. Also employed in polymer chemistry to create cross-linked structures due to its bifunctional nature. Its steric bulk helps control reaction selectivity, making it useful in fine chemical synthesis where precise functionalization is required.