In Hoffmann degradation of amide the correct order of reagent is :

Options

A. `Br_2, KOH ,H_2O`
B. ` KOH , Br _2 , H_2O`
C. ` H_2 o, KOH , Br _2 `
D. None of these

Answer

To solve the question regarding the correct order of reagents in the Hofmann degradation of amides, we will break down the process step by step.

### Step-by-Step Solution:

1. **Understanding the Reaction**:
The Hofmann degradation of amides involves the conversion of an amide into a primary amine with the release of carbon dioxide (CO2). The reaction requires specific reagents to proceed through several steps.

2. **First Reagent - Base (KOH)**:
The first reagent used in the Hofmann degradation is a strong base, typically potassium hydroxide (KOH). The base abstracts an acidic hydrogen from the amide, forming an anion. This step is crucial as it activates the amide for further reactions.

**Hint**: Remember that a strong base is necessary to initiate the reaction by deprotonating the amide.

3. **Second Reagent - Bromine (Br2)**:
After the formation of the anion, the next step involves the addition of bromine (Br2). The anion attacks the bromine, leading to the formation of an intermediate compound where a bromine atom is now attached to the nitrogen.

**Hint**: The bromination step is essential for the subsequent rearrangement and migration of groups.

4. **Final Step - Water (H2O)**:
The last reagent added is water (H2O). This step involves the hydrolysis of the intermediate formed in the previous steps, ultimately leading to the formation of a primary amine and the release of CO2.

**Hint**: Water is crucial for the final protonation and completion of the reaction.

5. **Order of Reagents**:
Based on the steps outlined, the correct order of reagents in the Hofmann degradation of amides is:
- First: KOH (base)
- Second: Br2 (bromine)
- Third: H2O (water)

### Conclusion:
Therefore, the correct order of reagents in the Hofmann degradation of amide is KOH, Br2, and H2O.

### Final Answer:
The correct option is KOH → Br2 → H2O.