Hofman bromamide degradation reaction is shown by…..

Options

A. `ArNH_(2)`
B. `ArCONH_(2)`
C. `ArNO_(2)`
D. `ArCH_(2)NH_(2)`

Explanation

To determine which compound undergoes the Hofmann bromamide degradation reaction, we need to analyze the given options and understand the reaction mechanism. The Hofmann bromamide degradation reaction specifically involves the conversion of an amide into a primary amine.

### Step-by-Step Solution:

1. **Understand the Hofmann Bromamide Degradation Reaction**:
- This reaction involves the conversion of an amide (RCONH2) into a primary amine (RNH2) using bromine (Br2) in the presence of a strong base like potassium hydroxide (KOH).
- The general reaction can be represented as:
\[ RCONH2 + Br2 + 4KOH \rightarrow RNH2 + 2KBr + 2H2O + K2CO3 \]

2. **Analyze the Options**:
- **Option A: ARNH2** (Aromatic amine)
- This is already an amine and does not contain an amide group. Therefore, it cannot undergo Hofmann degradation.
- **Option B: ARCONH2** (Aromatic amide)
- This contains an amide group (C=O and NH2). This is the correct structure that can undergo Hofmann bromamide degradation.
- **Option C: ARNO2** (Aromatic nitro compound)
- This compound does not contain an amide group, so it cannot undergo the reaction.
- **Option D: ARCH2NH2** (Aromatic primary amine)
- Similar to option A, this is already an amine and lacks an amide group, thus it cannot undergo Hofmann degradation.

3. **Conclusion**:
- From the analysis, only **Option B (ARCONH2)** contains an amide group and is capable of undergoing the Hofmann bromamide degradation reaction.

### Final Answer:
The correct answer is **B: ARCONH2**.