Answer: AlCl 3 binds the nitrogen lone pair.
- A the amino group directs to meta only
- B the benzene ring has no free positions
- C aniline is not an aromatic compound
- D AlCl<sub>3</sub> binds the nitrogen lone pair
Correct answer: D. AlCl<sub>3</sub> binds the nitrogen lone pair
Explanation: The Lewis acid AlCl<sub>3</sub> coordinates to the basic nitrogen lone pair, leaving the ring positively charged and deactivated.
In aniline, the nitrogen's lone pair is pulled into the benzene ring through resonance, leaving less electron density available to accept a proton - which is why aniline is a much weaker base than methylamine, where the lone pair is fully available.
Concept context
Nitrogen-containing organic compounds. Covers classification (primary, secondary, tertiary), basicity comparison, preparation methods, and reactions including diazotization and coupling, key for understanding dyes and pharmaceuticals.