Which of the following compounds is not chiral

Options

A. `DCH_(2)CH_(2)CH_(2)Cl`
B. `CH_(3)CH_(2)CHDCl`
C. `CH_(3)CHDCH_(2)CH_(2)Cl`
D. `CH_(3)CHClCH_(2)D`

Explanation

To determine which of the following compounds is not chiral, we need to identify the presence of chiral centers in each compound. A chiral center is typically a carbon atom that is bonded to four different substituents, leading to non-superimposable mirror images.

### Step-by-Step Solution:

1. **Identify the Compounds**: We have four compounds to analyze:
- Option 1: DCH2CH2CH2Cl
- Option 2: CH3CH3CH2CHDCl
- Option 3: CH3CHDCH2CH2Cl
- Option 4: CH3CHClCH2D

2. **Analyze Option 1 (DCH2CH2CH2Cl)**:
- The structure consists of a carbon chain with a chlorine atom attached.
- The carbon atoms in this compound do not have four different substituents.
- Therefore, there is no chiral center present in this compound.

3. **Analyze Option 2 (CH3CH3CH2CHDCl)**:
- This compound has a carbon (the one with D and Cl) that is attached to four different groups (two CH3 groups, one CH2 group, and one Cl).
- This indicates the presence of a chiral center, making the compound chiral.

4. **Analyze Option 3 (CH3CHDCH2CH2Cl)**:
- In this compound, the carbon with D and Cl is also attached to four different groups (CH3, CH2, CH2, and Cl).
- This means there is a chiral center, making this compound chiral as well.

5. **Analyze Option 4 (CH3CHClCH2D)**:
- Here, the carbon with Cl and D is attached to four different groups (CH3, CH2, D, and Cl).
- This confirms the presence of a chiral center, making this compound chiral.

6. **Conclusion**:
- After analyzing all options, we find that only **Option 1 (DCH2CH2CH2Cl)** does not have a chiral center and is therefore **not chiral**.

### Final Answer:
**Option 1 (DCH2CH2CH2Cl) is the compound that is not chiral.**

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