Which of the following will not give positive test with `CHCl_(3)//KOH`.

Options

A. `CH_(3)-CH_(2)-NH-CH_(3)`
B. `CH_(3)-CH_(2)-CH_(2)-NH_(2)`
C.
D. `CH_(3)-overset(CH_(3))overset(|)(CH)-NH_(2)`

Answer

To determine which compound will not give a positive test with chloroform (CHCl₃) and potassium hydroxide (KOH), we need to understand the carbylamine reaction. This reaction is specific to primary amines, where a primary amine reacts with chloroform and KOH to produce isocyanide (carbylamine).

### Step-by-Step Solution:

1. **Identify the Reaction**: The carbylamine reaction occurs between chloroform (CHCl₃) and KOH with primary amines to produce isocyanides. Secondary and tertiary amines do not undergo this reaction.

2. **Analyze Each Option**:
- **Option 1: CH₃CH₂NHCH₃** (Ethylmethylamine)
- This is a secondary amine because it has two alkyl groups attached to the nitrogen.
- **Conclusion**: It will NOT give a positive test with CHCl₃/KOH.

- **Option 2: CH₃CH₂CH₂NH₂** (Propylamine)
- This is a primary amine as it has one alkyl group attached to the nitrogen.
- **Conclusion**: It will give a positive test with CHCl₃/KOH.

- **Option 3: Aniline (C₆H₅NH₂)**
- Aniline is also a primary amine because it has one alkyl group (the phenyl group) attached to the nitrogen.
- **Conclusion**: It will give a positive test with CHCl₃/KOH.

- **Option 4: CH₃CHCH₃NH₂** (Isopropylamine)
- This is another primary amine as it has one alkyl group attached to the nitrogen.
- **Conclusion**: It will give a positive test with CHCl₃/KOH.

3. **Final Conclusion**: The only compound that will NOT give a positive test with chloroform and KOH is **Option 1: CH₃CH₂NHCH₃** (Ethylmethylamine), which is a secondary amine.

### Answer:
**Option 1: CH₃CH₂NHCH₃ will not give a positive test with CHCl₃/KOH.**