Question

An organic compound $[ A ]\left( C _4 H _{11} N \right)$, shows optical activity and gives $N _2$ gas on treatment with The structure of $A$ is :

• A.
• B.
• C.
• D.

Hint:

When identifying amines, consider their reaction with reagents like \( HNO_2 \) and Hinsberg reagent, which help differentiate primary, secondary, and tertiary amines.

Answer 1

The Correct Option is D

To identify the structure of the organic compound $[A]$ with molecular formula \(C_4H_{11}N\), which is optically active and releases \(N_2\) gas on treatment, we need to follow the reasoning steps below:

1. The given compound is a monoamine as it contains one nitrogen atom and follows the general formula \(C_nH_{2n+3}N\) for amines. Here, \(n = 4\).
2. The compound releases \(N_2\) gas upon treatment, which indicates it is likely to be a primary amine, as this is a typical reaction for them: they can form diazonium salts, which decompose to release nitrogen.
3. Optical activity in an organic compound indicates the presence of a chiral center, which is a carbon atom with four different substituents.
4. We need to identify a structure that exhibits both chirality (optical activity) and ability to form a diazonium salt (necessary to release \(N_2\)).
5. Among the provided options, we consider which has a chiral center. A chiral center requires four different groups/atoms around a carbon atom.
6. We examine Option 4:
7. The structure exhibits a carbon atom bonded to three methyl groups and a nitrogen atom, forming \(C*H(CH_3)_2NH_2\). This leads to chirality due to the asymmetric arrangement of substituents around this carbon.
8. This structure, identified as 2-aminobutane, can indeed undergo treatment to form a diazonium salt, releasing \(N_2\) gas upon decomposition.
9. Option 4 satisfies all conditions: it's a primary amine with a chiral center and can liberate \(N_2\).

Therefore, the correct answer is Option 4, which represents the structure of compound $[A]$.