Used primarily as a derivatizing agent in analytical chemistry, especially in gas chromatography (GC) and liquid chromatography (LC) for the detection and quantification of compounds containing active hydrogens, such as alcohols, phenols, and amines. It reacts readily to form stable esters or carbamates, enhancing volatility and detectability. Also employed in organic synthesis as an activating agent for carboxylic acids, facilitating peptide coupling or ester formation. Its reactivity makes it useful in the preparation of pharmaceuticals, agrochemicals, and other fine chemicals where controlled acyl transfer is required. Handle with care due to its lachrymatory and moisture-sensitive properties.