Question

Which of the following reactions does NOT yield an amine?

• A. R-X + NH\(_3\) (alco) \(\rightarrow\) \text{Amine}
• B. R-NO\(_2\) \xrightarrow{Sn / \text{conc. HCl}} \text{Amine}
• C. R-CH=NOH \xrightarrow{Na} \text{Amine}
• D. R-CN + H\(_2\)O \(\xrightarrow{H^+}\) \text{Amine}

Hint:

The reaction of nitriles (R-CN) with water and acid forms amides, not directly amines.

Answer 1

The Correct Option is D

Step 1: Analyzing the reactions.
- In the first reaction, alkyl halide (R-X) reacts with ammonia (NH\(_3\)) in alcohol to form an amine. This is a nucleophilic substitution reaction that yields an amine.
- In the second reaction, nitro compound (R-NO\(_2\)) is reduced to form an amine, using tin (Sn) and concentrated hydrochloric acid (HCl). This is a reduction reaction that forms an amine.
- In the third reaction, the hydroxylamine group (R-CH=NOH) undergoes reduction with sodium (Na) to form an amine.
- In the fourth reaction, a nitrile (R-CN) undergoes hydrolysis to form an amide (R-C(O)NH\(_2\)), which is further hydrolyzed to form an amine under acidic conditions. Therefore, it is an amide intermediate, not a direct amine.

Step 2: Analyzing the options.
(A) R-X + NH\(_3\) (alco): Correct. This yields an amine.
(B) R-NO\(_2\) + Sn / conc. HCl: Correct. This yields an amine.
(C) R-CH=NOH + Na: Correct. This yields an amine.
(D) R-CN + H\(_2\)O \(\xrightarrow{H^+}\): Incorrect. This does not directly yield an amine but first forms an amide.

Step 3: Conclusion.
The reaction that does not yield an amine is R-CN + H\(_2\)O \(\xrightarrow{H^+}\), corresponding to option (D).