Which of the following compounds may not exist as enantiomers ?

Options

A. `CH_(3)CH(OH)CO_(2)H`
B. `CH_(3)CH_(2)CH(CH_(3)) CH_(2)OH`
C. `C_(6)H_(5)CH_(2)CH_(3)`
D. `C_(6)H_(5)CHiCH_(3)`

Explanation

To determine which of the given compounds may not exist as enantiomers, we need to analyze the structures of each compound and identify whether they contain a chiral center. A compound is chiral if it has at least one chiral center, which is typically a carbon atom bonded to four different substituents.

### Step-by-Step Solution:

1. **Identify the Compounds**:
We have four compounds to analyze. Let's denote them as Compound 1, Compound 2, Compound 3, and Compound 4.

2. **Draw the Structures**:
- **Compound 1**: CH3-C(OH)(H)-C(=O)(OH)
- **Compound 2**: CH3-C(H)(H)-C(CH3)(CH2OH)
- **Compound 3**: C6H5-C(H)(H)-C(CH3)(H)
- **Compound 4**: C6H5-C(H)(I)-C(CH3)(H)

3. **Identify Chiral Centers**:
- **Compound 1**: The carbon with OH, H, and the carbon chain is a chiral center (four different groups).
- **Compound 2**: The carbon connected to two hydrogens is not a chiral center (two identical groups).
- **Compound 3**: The carbon connected to two hydrogens is not a chiral center (two identical groups).
- **Compound 4**: The carbon connected to Iodine, Hydrogen, and the carbon chain is a chiral center (four different groups).

4. **Conclusion**:
- Compound 1 has a chiral center and can exist as enantiomers.
- Compound 2 does not have any chiral center and cannot exist as enantiomers.
- Compound 3 does not have any chiral center and cannot exist as enantiomers.
- Compound 4 has a chiral center and can exist as enantiomers.

5. **Final Answer**:
The compounds that may not exist as enantiomers are **Compound 2** and **Compound 3**. However, since the question asks for one option, we can select **Compound 3** as the answer.