Answer: Forms insoluble sulfonamide (no N-H, insoluble in NaOH).
- A Forms insoluble sulfonamide (no N-H, insoluble in NaOH)
- B Forms a soluble sulfonamide that dissolves readily in NaOH
- C Gives no reaction since secondary amines lack a reactive N-H
- D Forms a simple ammonium salt with the sulfonyl chloride
Correct answer: A. Forms insoluble sulfonamide (no N-H, insoluble in NaOH)
Explanation: Secondary amines give an N-disubstituted sulfonamide which is insoluble in NaOH.
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.