In organic reactions, the order of reagents and the type of functional group transformations are key in determining the structure of the products. Follow the sequence of steps carefully to identify the correct product.
Step 1: Understanding the reaction steps.
Let's break down the reactions step by step.
- Step 1: Bromination of the aromatic ring (A).
The reaction of \( \text{Br}_2 \) with \( \text{Fe} \) is a bromination reaction, resulting in the formation of 2-bromo-nitrobenzene (A), where the bromine replaces a hydrogen atom on the benzene ring.
- Step 2: Reduction of 2-bromo-nitrobenzene (B).
The reduction of 2-bromo-nitrobenzene in acidic conditions using tin (Sn) results in the reduction of the nitro group to an amine group. This will give us 2-bromoaniline (B).
- Step 3: Diazotization of 2-bromoaniline (C).
The reaction with sodium nitrite (\( \text{NaNO}_2 \)) in the presence of hydrochloric acid results in the diazotization of the amine group, forming a diazonium ion.
- Step 4: Substitution of the diazonium ion with a hydroxyl group (D).
The reaction of the diazonium salt in ethanol (\( \text{EtOH} \)) leads to the substitution of the diazonium ion with a hydroxyl group, resulting in the formation of 2-bromo-phenol (D).
- Step 5: Oxidation of 2-bromo-phenol (E).
The oxidation with potassium permanganate (\( \text{KMnO}_4 \)) results in the oxidation of the hydroxyl group to a carboxyl group, forming 2-bromobenzoic acid (E).
Step 2: Conclusion.
From the steps above, we conclude that the product \( E \) is 2-bromobenzoic acid and the intermediate product \( A \) is 2-bromo-nitrobenzene. Therefore, the correct answer is option (B).
Final Answer: (B) \( \text{COOH} \) and \( \text{Br} \)
