Which of the following compound does undergo aldol condensation

Options

A. HCHO
B. `CH_3-underset(CH_3)underset(|)overset(CH_3)overset(|)C-CHO`
C. `"CCl"._3 CHO`
D. `CH_3.CH_2.CHO`

Answer

To determine which of the given compounds undergoes aldol condensation, we need to follow these steps:

### Step 1: Identify the Compounds
We have four compounds to analyze. Let's denote them as:
1. Compound A: HCHO (Formaldehyde)
2. Compound B: (Compound structure not provided in the transcript)
3. Compound C: CCl3CHO (Trichloroacetaldehyde)
4. Compound D: (Compound structure not provided in the transcript)

### Step 2: Check for Alpha Hydrogen
Aldol condensation requires the presence of alpha hydrogen atoms. Alpha hydrogen atoms are those that are attached to the carbon adjacent to the carbonyl group (C=O).

- **Compound A (HCHO)**:
- Structure: H2C=O
- Alpha Carbon: None (no carbon adjacent to the carbonyl group)
- Conclusion: No alpha hydrogen, will not undergo aldol condensation.

- **Compound B**:
- (Assuming it has no alpha hydrogens based on the transcript)
- Conclusion: Will not undergo aldol condensation.

- **Compound C (CCl3CHO)**:
- Structure: CCl3-CHO
- Alpha Carbon: CCl3 has no hydrogen atoms.
- Conclusion: No alpha hydrogen, will not undergo aldol condensation.

- **Compound D**:
- (Assuming it has alpha hydrogens based on the transcript)
- Conclusion: Will undergo aldol condensation.

### Step 3: Conclusion
From the analysis:
- **Only Compound D** has alpha hydrogens and can undergo aldol condensation.

### Final Answer
The compound that undergoes aldol condensation is **Compound D**.

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