Used primarily as an intermediate in organic synthesis, particularly in the production of pharmaceuticals and agrochemicals. It acts as a chloroacylating agent, facilitating the introduction of chloroformyl or chloromethyl groups into target molecules. Commonly employed in the preparation of esters, carbamates, and other functionalized derivatives. Its reactivity makes it suitable for use in controlled reactions where selective protection or activation of functional groups is required. Due to its lachrymatory and corrosive nature, handling requires strict safety controls. Typically not used in final products but serves a critical role in multi-step synthetic pathways.