Question

Which will not go for diazotization?

• A. A
• B. B
• C. C
• D. D

Hint:

Only primary aromatic amines form stable diazonium salts; aliphatic amines do not because diazonium salts decompose.

Answer 1

The Correct Option is B

Step 1: Meaning of diazotization.
Diazotization is the reaction of primary aromatic amines with nitrous acid (NaNO\(_2\)/HCl at 0–5°C) to form diazonium salts.
Step 2: Check each option.
(A) Aniline (C\(_6\)H\(_5\)NH\(_2\)) is primary aromatic amine \(\Rightarrow\) undergoes diazotization.
(C) Toluidine derivative \(\Rightarrow\) still primary aromatic amine \(\Rightarrow\) undergoes diazotization.
(D) Nitroaniline derivative \(\Rightarrow\) still aromatic primary amine (though slower) \(\Rightarrow\) undergoes diazotization.
(B) Benzylamine (C\(_6\)H\(_5\)CH\(_2\)NH\(_2\)) is primary aliphatic amine (amino group not directly on aromatic ring).
Aliphatic diazonium salts are unstable and decompose immediately, so it is considered that it does not undergo diazotization.
Final Answer:
\[ \boxed{\text{(B) C\(_6\)H\(_5\)CH\(_2\)NH\(_2\)}} \]