NEET 2026 (Phase 1) · ChemistryHNO2 matchPrevious Year Question

The following two reactions give the same foul-smelling product Z. X and Z, respectively, are:

Answer: (A) (A) ; . \textbf{Answer:} (A) converts the alkyl halide to the foul-smelling isocyanide , which is the same product Z formed by the carbylamine reaction.

  1. A.(A) ;
  2. B.(B) ;
  3. C.(C) ;
  4. D.(D) ;

Correct Answer

(A) (A) ;

Solution & Explanation

\textbf{Answer:} (A) converts the alkyl halide to the foul-smelling isocyanide , which is the same product Z formed by the carbylamine reaction. \textbf{Solution:} Second path (fixes Z): Propanamide undergoes Hoffmann bromamide degradation to ethylamine (one less carbon): . This primary amine then undergoes the carbylamine reaction with chloroform and ethanolic to give the foul-smelling isocyanide: . So (ethyl isocyanide). First path (fixes X): To get the same isocyanide from , the reagent must be silver cyanide: is mainly covalent and the nitrogen lone pair attacks, giving the isocyanide . ( is ionic and would give the nitrile , the wrong product.) Therefore and , i.e. option (A).

🎯
43,000+ questions in हिंदी & English · one-tap toggle
Practice NEET 2026 (Phase 1) Chemistry — free, with instant solutions
43,000+ NEET questions solved step-by-step, chapter-wise, in the MedicNEET app.
📚Practice all NEET Chemistry PYQs chapter-wise 💡Don't get it? Learn the Amines concepts