Question

Identify ‘A’ and ‘B’ respectively in the following reaction: \[ \text{Toluene} \xrightarrow{\text{Cl}_2, \, \text{hv}} A \xrightarrow{\text{H}_2\text{O}, \, \Delta} B \] What are the products A and B?

• A. Benzoyl chloride and benzoic acid
• B. Benzoyl chloride and benzaldehyde
• C. Benzyl chloride and benzoic acid
• D. Benzyl chloride and benzaldehyde

Hint:

The chlorination of toluene in the presence of UV light produces benzyl chloride, and subsequent hydrolysis produces benzaldehyde.

Answer 1

The Correct Option is D

Step 1: Understanding the reaction.
The first part of the reaction involves the chlorination of toluene (methylbenzene) in the presence of UV light (\( \text{hv} \)). Chlorination of the methyl group in toluene leads to the formation of benzyl chloride (A). The second part of the reaction involves hydrolysis of benzyl chloride in the presence of heat (\( \Delta \)), which results in the formation of benzaldehyde (B).
Step 2: Analyzing the options.
(A) Benzoyl chloride and benzoic acid: Incorrect — Benzoyl chloride would not form from the chlorination of the methyl group in toluene.
(B) Benzoyl chloride and benzaldehyde: Incorrect — Benzoyl chloride does not form in the first step.
(C) Benzyl chloride and benzoic acid: Incorrect — The second step results in benzaldehyde, not benzoic acid.
(D) Benzyl chloride and benzaldehyde: Correct — The first step forms benzyl chloride, and the second step forms benzaldehyde.
Step 3: Conclusion.
The correct answer is (D) Benzyl chloride and benzaldehyde.