Question

Convert Benzene to Aniline in not more than two steps.

Hint:

{Benzene → Nitrobenzene → Aniline} Nitration then reduction.

Answer 1

Concept: Aniline (\(C_6H_5NH_2\)) can be prepared from benzene by introducing a nitro group followed by reduction. This is a standard two-step aromatic substitution and reduction sequence.
Step 1: Nitration of Benzene Benzene is treated with a mixture of concentrated nitric acid and concentrated sulfuric acid (nitrating mixture) to form nitrobenzene. \[ C_6H_6 \xrightarrow[\text{conc. } H_2SO_4]{\text{conc. } HNO_3} C_6H_5NO_2 \]
Step 2: Reduction of Nitrobenzene Nitrobenzene is reduced to aniline using reducing agents such as:

• Sn/HCl or Fe/HCl (followed by NaOH)
• Catalytic hydrogenation (H\(_2\)/Pd)

\[ C_6H_5NO_2 \xrightarrow{\text{Sn/HCl}} C_6H_5NH_2 \] Overall Conversion: \[ \text{Benzene} \rightarrow \text{Nitrobenzene} \rightarrow \text{Aniline} \] Conclusion: Thus, benzene can be converted to aniline in two steps: nitration followed by reduction of the nitro group.