Question

The reaction 

• A. Rosenmund's reaction
• B. Stephen's reaction
• C. Cannizzaro's reaction
• D. Gattermann-Koch reaction

Hint:

The Gattermann-Koch reaction is a formylation reaction where benzene reacts with carbon monoxide (\( \text{CO} \)) and hydrochloric acid (\( \text{HCl} \)) in the presence of \(\text{AlCl}_3\) or \(\text{CuCl}\) to form benzaldehyde.

Answer 1

The Correct Option is D

Step 1: Reaction Mechanism Analysis
The reaction described synthesizes benzaldehyde from benzene using carbon monoxide (\( \text{CO} \)) and hydrochloric acid (\( \text{HCl} \)) catalyzed by anhydrous aluminum chloride (\( \text{AlCl}_3 \)) or cuprous chloride (\( \text{CuCl} \)). 
Step 2: Identification of the Reaction Name 
This process is identified as the Gattermann-Koch reaction, a method for benzaldehyde synthesis from benzene. 
Step 3: Exclusion of Alternative Reactions 
- Rosenmund’s reaction: Reduction of acyl chlorides to aldehydes; not applicable.  
- Stephen’s reaction: Partial reduction of nitriles to imines, followed by hydrolysis to aldehydes. 
- Cannizzaro’s reaction: Disproportionation of aldehydes lacking alpha-hydrogen atoms. Therefore, the Gattermann-Koch reaction is the correct designation. 

Final Answer: The described reaction corresponds to the Gattermann-Koch reaction.