Which of the following compounds will undergo Cannizzaro reaction ?

Options

A. `CH_(3)CHO`
B. `CH_(3)COCH_(3)`
C. `C_(6)H_(5)CHO`
D. `C_(6)H_(5)CH_(2)CHO`

Explanation

To determine which of the given compounds will undergo the Cannizzaro reaction, we need to understand the conditions required for this reaction to occur. The Cannizzaro reaction is a redox reaction that occurs with aldehydes that do not have alpha hydrogens.

### Step-by-Step Solution:

1. **Identify the Cannizzaro Reaction**:
- The Cannizzaro reaction occurs with aldehydes that lack alpha hydrogens. In this reaction, one molecule of the aldehyde is oxidized to a carboxylic acid, while another molecule is reduced to an alcohol.

2. **Analyze the Given Compounds**:
- We need to examine each compound to see if they contain alpha hydrogens.

3. **Option 1: Acetaldehyde (CH₃CHO)**:
- Acetaldehyde has the structure CH₃CHO. It contains one alpha hydrogen (the hydrogen on the methyl group).
- **Conclusion**: Acetaldehyde cannot undergo the Cannizzaro reaction.

4. **Option 2: Acetone (CH₃COCH₃)**:
- Acetone has the structure CH₃COCH₃. It is a ketone and contains six alpha hydrogens (three from each methyl group).
- **Conclusion**: Acetone cannot undergo the Cannizzaro reaction.

5. **Option 3: Benzaldehyde (C₆H₅CHO)**:
- Benzaldehyde has the structure C₆H₅CHO. It does not have any alpha hydrogens because the carbonyl carbon is directly attached to a phenyl group.
- **Conclusion**: Benzaldehyde can undergo the Cannizzaro reaction.

6. **Option 4: Propanal (C₂H₅CHO)**:
- Propanal has the structure C₂H₅CHO. It contains two alpha hydrogens (the two hydrogens on the ethyl group).
- **Conclusion**: Propanal cannot undergo the Cannizzaro reaction.

### Final Answer:
The compound that can undergo the Cannizzaro reaction is **Benzaldehyde (Option 3)**.

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