Used primarily as an intermediate in the synthesis of agrochemicals and pharmaceuticals. Its reactive sulfonyl chloride group enables the formation of sulfonamides, which are key structural motifs in certain herbicides and fungicides. It is also employed in the production of dyes and pigments due to its ability to form stable aromatic sulfonate esters. In research, it serves as a sulfonating agent for introducing the 2-chloro-4-methylphenylsulfonyl group to modify organic molecules, enhancing their stability or biological activity.