Which of the following will not undergo aldol condensation ?

Options

A. `CH_(3)-CHO`
B.
C. `CH_(3)-overset(O)overset(||)C-CH_(3)`
D. `CH_(3)-overset(CH_(3))overset(|)underset(CH_(3))underset(|)C-CHO`

Explanation

To determine which of the given compounds will not undergo aldol condensation, we need to understand the requirement for this reaction. Aldol condensation requires the presence of at least one alpha hydrogen atom attached to the carbon adjacent to the carbonyl group.

Let's analyze each option step by step:

### Step 1: Identify the Compounds
The given options are:
1. **A**: CH3CHO (Acetaldehyde)
2. **B**: C6H5CHO (Benzaldehyde)
3. **C**: CH3COCH3 (Acetone)
4. **D**: (CH3)2C(CHO) (Tertiary butyl aldehyde)

### Step 2: Analyze Each Compound for Alpha Hydrogen
- **Option A: CH3CHO (Acetaldehyde)**
- The carbonyl carbon is attached to a methyl group (CH3), which has three alpha hydrogens.
- **Conclusion**: It can undergo aldol condensation.

- **Option B: C6H5CHO (Benzaldehyde)**
- The carbonyl carbon is attached to a phenyl group (C6H5), which does not have any alpha hydrogens because the carbon is fully bonded (4 bonds) with no hydrogens left.
- **Conclusion**: It cannot undergo aldol condensation.

- **Option C: CH3COCH3 (Acetone)**
- The carbonyl carbon is attached to two methyl groups (CH3), each having three alpha hydrogens.
- **Conclusion**: It can undergo aldol condensation.

- **Option D: (CH3)2C(CHO) (Tertiary butyl aldehyde)**
- The carbonyl carbon is attached to two methyl groups and one aldehyde group. The alpha carbon (the one adjacent to the carbonyl) has no hydrogen atoms because it is fully bonded.
- **Conclusion**: It cannot undergo aldol condensation.

### Step 3: Final Conclusion
From the analysis, we find:
- **Option B (Benzaldehyde)** does not have any alpha hydrogen and cannot undergo aldol condensation.
- **Option D (Tertiary butyl aldehyde)** also does not have any alpha hydrogen and cannot undergo aldol condensation.

Thus, the compounds that will not undergo aldol condensation are **B and D**.