(i) nitrobenzene → acetanilide

Nitrobenzene is reduced to aniline in the presence of Sn/HCl. The amino group of aniline is then acetylated with acetic anhydride in the presence of pyridine.

(ii) acetanilide → p-nitroaniline

Acetanilide is allowed to react with nirating mixture to form p-Nitroacetanilide. P-nitroacetanilide is then converted to p-nitroaniline by hydrolysis.