Catalytic hydrogenation of phenyl diazonium bromide produces

Options

A. phenylhydrazine
B. bromobenzene
C. benzene
D. phenylamine

Explanation

To solve the question regarding the catalytic hydrogenation of phenyl diazonium bromide, we can break down the process step by step.

### Step-by-Step Solution:

1. **Understanding Phenyl Diazonium Bromide**:
- Phenyl diazonium bromide has the structure of a benzene ring (C6H5) attached to a diazonium group (N2+), which is represented as C6H5-N2+Br-. The diazonium group contains a nitrogen-nitrogen triple bond (N≡N).

2. **Catalytic Hydrogenation Process**:
- Catalytic hydrogenation involves the addition of hydrogen (H2) in the presence of a catalyst, typically nickel (Ni), platinum (Pt), or palladium (Pd). This process is used to reduce unsaturated compounds to saturated compounds.

3. **Reduction of the Diazonium Group**:
- In the case of phenyl diazonium bromide, the N≡N bond is an unsaturated bond. When hydrogen is added, this bond gets reduced. The first step results in the formation of a nitrogen double bond (N=N), leading to the intermediate product C6H5-N=NH-Br.

4. **Further Reduction**:
- The next step involves the reduction of the N=NH bond. The hydrogenation continues, and the N=NH bond is converted into a saturated bond, resulting in the formation of phenyl hydrazine (C6H5-NH-NH2).

5. **Final Product**:
- The final product of the catalytic hydrogenation of phenyl diazonium bromide is phenyl hydrazine (C6H5-NH-NH2).

6. **Conclusion**:
- Among the given options, phenyl hydrazine is the correct answer.

### Final Answer:
The product formed from the catalytic hydrogenation of phenyl diazonium bromide is **phenyl hydrazine**.