Which of the following conversions can be carried out by clemmensen reduction
I Benzaldehyde into benzyl alcohol.
II cyclohexanone into cycloheaxane
III Benzophenone into diphenyl methane.
Select the correct option.

Options

A. I and III
B. Only II
C. II and III
D. Only I

Answer

To determine which conversions can be carried out by Clemmensen reduction, we first need to understand what Clemmensen reduction entails. Clemmensen reduction is a method used to convert carbonyl compounds (aldehydes and ketones) into alkanes using zinc amalgam (Zn/Hg) and hydrochloric acid (HCl) as a catalyst.

Now, let's analyze each option provided:

### Step 1: Analyze the conversions

1. **Benzaldehyde into Benzyl Alcohol**:
- Benzaldehyde (C6H5CHO) is an aldehyde.
- Clemmensen reduction typically converts carbonyl groups to alkanes, not alcohols.
- Therefore, this conversion **cannot** be achieved through Clemmensen reduction.

2. **Cyclohexanone into Cyclohexane**:
- Cyclohexanone (C6H10O) is a ketone.
- Clemmensen reduction can convert ketones into alkanes.
- Thus, cyclohexanone can be reduced to cyclohexane (C6H12) using this method.
- This conversion **can** be achieved through Clemmensen reduction.

3. **Benzophenone into Diphenylmethane**:
- Benzophenone (C6H5)2CO is also a ketone.
- Clemmensen reduction can convert ketones into alkanes.
- Therefore, benzophenone can be reduced to diphenylmethane (C6H5)2CH2 using this method.
- This conversion **can** be achieved through Clemmensen reduction.

### Step 2: Conclusion
Based on the analysis:
- **I**: Cannot be carried out by Clemmensen reduction.
- **II**: Can be carried out by Clemmensen reduction.
- **III**: Can be carried out by Clemmensen reduction.

Thus, the correct answer is that **II and III can be carried out by Clemmensen reduction**.

### Final Answer:
The correct options are II and III.

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