Question

Which of the following reactions uses diazonium salt ?

• A. Sandmeyer reaction
• B. Mendius reaction
• C. Hofmann rearrangement reaction
• D. carbylamine reaction

Hint:

Sandmeyer converts aryl diazonium salt to aryl halide using CuX.

Answer 1

The Correct Option is A

Step 1: Where diazonium salts appear:
They are produced from aniline with $\text{NaNO}_2$ and HCl at 273-278 K and then used for substitution.

Step 2: Check each reaction:
Mendius: nitrile to amine. Hofmann: amide to amine. Carbylamine: amine to isocyanide. Sandmeyer: $\text{ArN}_2^+ \to \text{ArX}$ with CuX.

Step 3: Result:
Only Sandmeyer involves the diazonium salt, option (A).

Final Answer:
Sandmeyer is the diazonium reaction. \[ \boxed{\text{(A) }\text{Sandmeyer reaction}} \]