Preparation: reduction of nitro compounds, Hoffmann bromamide degradation
Amines and Diazonium Salts · Chemistry
Study notes
Prepare aniline from nitrobenzene. Which reduction? Step 1: ArNO₂ + Sn/conc. HCl (or Fe/HCl) → ArNH₂ — classic lab method. Step 2: Mechanism passes through nitroso → hydroxylamine → amine. Step 3: Industrial: catalytic hydrogenation (H₂/Ni or Pt). Step 4: For aliphatic amines: Hoffmann bromamide (RCONH₂ → RNH₂, one carbon shorter) or Gabriel synthesis. Choose by target!