NCERT · Class 12 · Chemistry · AminesWhat is Hinsberg's reagent and what is its use?

Hinsberg's reagent is benzene sulphonyl chloride ($C_6H_5SO_2Cl$). Its primary application in organic chemistry is in the separation and identification of primary, secondary, and tertiary amines. Primary amines react with it to form an N-substituted sulphonamide which is soluble in alkali. Secondary amines form a sulphonamide that is insoluble in alkali due to the absence of acidic hydrogen on nitrogen, whereas tertiary amines do not react with Hinsberg's reagent at all.