While numerous reagents are available for the preparation of derivatives of the three classes of amines, only two, nitrous acid and aryl sulfonyl chlorides, have been used to any considerable extent as a means of separating the different types of amines from each other when they occur in a mixture. Nitrous acid has the disadvantage of destroying completely the identity of the primary amine, often with the formation of a rearranged product. Aryl ...
