Used primarily as an intermediate in the synthesis of pharmaceuticals and agrochemicals. Its sulfonyl chloride group readily reacts with amines and alcohols, making it valuable for constructing sulfonamides and sulfonate esters—key motifs in drug design. Commonly employed in the development of herbicides and fungicides due to the enhanced bioactivity imparted by the chloro and methoxy substituents. Also utilized in the preparation of dyes and functional materials where aromatic sulfonyl derivatives are required. Its reactivity allows for selective derivatization in multi-step organic syntheses.