4.4.1 Reactions of other Nitrogen Nucleophiles

• • Acid chloride, anhydrides and esters react with hydrazine to provide acid hydrazides which are less nucleophilic and the further acylation requires a more vigorous conditions. Thus, monoacylated product can be obtained in high yield.



• • Hydroxylamine reacts with carboxylic acid derivatives giving hydroxyamic acids.



• • Reaction of acid chloride with sodium azide gives acid azide which is the substrate precursor for Curtius rearrangement.

4.5 Reactions of Electrophilic Nitrogen

Four electrophilic nitrogen containing groups, nitroso (-NO), nitro (-NO₂), arylazo (-N=NAr), and arylimino (=NAr), could be bonded to aliphatic carbon via C-N bond formation.

4.5.1 Nitrosation

The reactions of nitroso group may be done by two ways. In first, enols react with nitrous acid or an organic nitrite by an acid-catalyzed process. The electrophile is to be the nitrosonium ion, NO⁺.