Question

Identify the product formed (A and E)

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is C

Correct answer is (c)

Answer 2

The reaction involves the following steps: 1. Step A: Bromination of the aromatic ring using Br$_2$ in the presence of Fe results in the selective addition of bromine to the meta position relative to the existing nitro group (NO$_2$) due to its electron-withdrawing nature.
2. Step B: Diazonium salt formation occurs when the amine (NH$_2$) group reacts with NaNO$_2$ and HCl under cold conditions.
3. Step C: Hydrolysis of the diazonium salt using H$_3$PO$_4$ replaces the diazo group (-N$_2^+$) with a hydroxyl group (-OH).
4. Step D: Oxidation with KMnO$_4$ under basic conditions results in the conversion of the alkyl group (-Me) to a carboxylic acid (-COOH).
5. Step E: Reaction with dilute acid (H$^+$) ensures completion and stability of the carboxylic acid group.
The final products are as follows:
- A: 3-bromo-4-nitrobenzene
- E: 3-bromo-4-nitrobenzoic acid
The key to solving this question lies in understanding the regioselectivity of each step:
- Bromination occurs at the meta position relative to NO$_2$ due to its electron-withdrawing nature.
- The diazonium salt intermediate facilitates substitution with a hydroxyl group.
- Oxidation converts the methyl group to a carboxylic acid, resulting in the final product.