MP Board · Class 12 · Chemistry · AminesWhy is aniline acetylated before carrying out nitration?

Aniline is acetylated prior to nitration because the amino group in aniline is strongly activating and ortho/para-directing, which makes direct nitration produce a complex mixture of tarry oxidation products along with poly-nitro derivatives in vigorous reactions. Acetylation with acetic anhydride protects the amino group by decreasing its electron-donating capacity through resonance with the carbonyl group, thus moderating the activating effect and yielding the p-nitroacetanilide as the major controlled product upon nitration.