Libermann reaction is given only by :

Options

A. primary amine
B. Secondary amine
C. Tertiary amine
D. none of these

Answer

**Step-by-Step Solution:**

1. **Understanding Liebermann Reaction**: The Liebermann reaction, also known as the Liebermann nitroso reaction, is a specific chemical reaction that involves the conversion of secondary amines into nitrosamines when treated with nitrous acid (HNO2).

2. **Identifying the Reactants**: The reaction involves secondary amines, which are characterized by having two organic groups attached to the nitrogen atom. In this case, we are looking for compounds that can undergo this reaction.

3. **Analyzing the Options**:
- **Option 1: Primary Amine**: Primary amines react with nitrous acid to form unstable diazonium salts, which decompose to give alcohol and nitrogen gas. Therefore, primary amines do not undergo the Liebermann reaction.
- **Option 2: Secondary Amine**: Secondary amines can react with nitrous acid to form stable nitrosamines, which is the hallmark of the Liebermann reaction. This option is likely correct.
- **Option 3: Tertiary Amine**: Tertiary amines do not react with nitrous acid to form nitrosamines, as they lack a hydrogen atom on the nitrogen that is necessary for the reaction. Thus, this option is incorrect.
- **Option 4: None of the Above**: Since we have identified that secondary amines do undergo the Liebermann reaction, this option is also incorrect.

4. **Conclusion**: Based on the analysis of the options, the only type of amine that participates in the Liebermann reaction is the secondary amine.

**Final Answer**: The Liebermann reaction is given only by secondary amines.

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