Question

In Gatterman reaction, which of the following catalyst is used?

• A. CO, HCl and anhyd. \(\text{AlCl}_3\)
• B. Copper powder and HBr
• C. Cu + Aq. \(\text{NaNO}_2\)
• D. KOH + \(\text{Br}_2\)

Hint:

Gattermann reaction uses copper powder with HX, while Sandmeyer uses Cu(I) salts.

Answer 1

The Correct Option is B

Step 1: Separate similar named reactions:
Sandmeyer: $\text{CuCl/HCl}$ or $\text{CuBr/HBr}$. Gattermann: Cu powder with HX. Gattermann-Koch: CO + HCl + $\text{AlCl}_3$ to give benzaldehyde.

Step 2: Pick:
The Gattermann reaction uses copper powder with HBr or HCl, option B.

Final Answer:
Gattermann uses Cu powder with HX; option A is Gattermann-Koch. \[ \boxed{\text{(B) }\text{Copper powder and HBr}} \]