Question

\(A\) is a neutral organic compound (M.F.: \(C_8H_9ON\)). On treatment with aqueous \(Br_2/HO^-\), \(A\) forms a compound \(B\) which is soluble in dilute acid. \(B\) on treatment with aqueous \(NaNO_2/HCl\) (0--5\(^\circ\)C) produces a compound \(C\) which on treatment with \(CuCN/NaCN\) produces \(D\). Hydrolysis of \(D\) produces \(E\) which is also obtainable from the hydrolysis of \(A\). \(E\) on treatment with acidified \(KMnO_4\) produces \(F\). \(F\) contains two different types of hydrogen atoms. The structure of \(A\) is 

• A. C
• B. A
• C. B
• D. D

Answer 1

The Correct Option is A

Let's determine the structure of compound \(A\) given its molecular formula and reactions.

1. The compound \(A\) with the molecular formula \(C_8H_9ON\) is a neutral organic compound. This suggests it might be an amide or aniline derivative.
2. Upon treatment with aqueous \(Br_2/HO^-\), \(A\) forms a compound \(B\) which is soluble in dilute acid. This reaction implies that \(A\) is an aromatic amide, likely undergoing a Hoffman degradation to form an amine.
3. Compound \(B\) on treatment with \(NaNO_2/HCl\) forms a diazonium salt \(C\). For this, \(B\) must be a primary aromatic amine.
4. The diazonium compound \(C\) reacts with \(CuCN/NaCN\) to form \(D\). This is the Sandmeyer reaction, replacing the diazonium group with a cyano group.
5. The compound \(D\), when hydrolyzed, forms compound \(E\), which can also be directly obtained from hydrolyzing \(A\). This suggests that \(E\) is a carboxylic acid.
6. Compound \(E\) on oxidation with acidified \(KMnO_4\) forms \(F\) with two different types of hydrogen atoms. This suggests \(F\) is a benzoic acid derivative.

Considering the transformations, the pathway indicates that \(A\) is likely acetanilide (C), an amide derivative of aniline: