Compound `[X ] C_(4) H_(11) N` reacts with `p-` toluene sulphonyl chloride in aqueous NaOH to give a solid. The compound [X] is :

Options

A. `CH_3 - CH_2 - CH_2 - CH_2 - NH_2`
B. `H_(3) C - underset(underset(CH_3)(|))CH - CH_2 - NH_2`
C. `CH_(3) CH_(2) - NH - CH_(2) - CH_(3)`
D. `H_(3) C - CH_2 - underset(underset(CH_3)(|))(N)- CH_3`

Answer

To solve the problem, we need to identify the compound [X] with the formula C₄H₁₁N that reacts with para-toluene sulphonyl chloride in aqueous NaOH to yield a solid product. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Reactants
- The compound [X] has the formula C₄H₁₁N, indicating it is an amine.
- Para-toluene sulphonyl chloride (p-TsCl) is a reagent used to distinguish between primary, secondary, and tertiary amines.

### Step 2: Identify the Type of Amine
- Primary amines (1°) have one carbon chain attached to the nitrogen (N) and two hydrogen atoms.
- Secondary amines (2°) have two carbon chains attached to the nitrogen and one hydrogen atom.
- Tertiary amines (3°) have three carbon chains attached to the nitrogen and no hydrogen atoms.

### Step 3: Analyze the Reaction with p-TsCl
- Tertiary amines do not react with p-TsCl because they lack a hydrogen atom on the nitrogen.
- Primary and secondary amines will react with p-TsCl, forming sulphonamides.
- The question states that the reaction produces a solid product, which typically indicates that the amine is a secondary amine.

### Step 4: Determine Possible Structures for C₄H₁₁N
- The possible structures for C₄H₁₁N can be:
1. Butylamine (1°)
2. Isobutylamine (1°)
3. Sec-butylamine (2°)
4. Tert-butylamine (3°)

### Step 5: Eliminate Options
- Since tertiary amines do not react with p-TsCl, we can eliminate tert-butylamine.
- Both butylamine and isobutylamine are primary amines and would not yield a solid product with p-TsCl.
- This leaves us with sec-butylamine as the only candidate that is a secondary amine.

### Step 6: Confirm the Product
- When sec-butylamine reacts with p-TsCl, it will form a sulphonamide which is a solid compound.
- Therefore, the compound [X] must be sec-butylamine.

### Conclusion
The compound [X] is **sec-butylamine**.

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