Which of the following compounds is optically active ?

Options

A.
B.
C.
D.

Answer

To determine which of the given compounds is optically active, we need to follow these steps:

### Step 1: Identify Chiral Centers
A compound is optically active if it contains at least one chiral carbon atom. A chiral carbon is defined as a carbon atom that is bonded to four different groups.

### Step 2: Analyze Each Compound
We will analyze each compound provided in the question to check for chiral centers and symmetry.

#### Compound 1:
- Structure: Benzene ring with substituents.
- Analysis: This compound has multiple chiral centers, but it also exhibits symmetry. If we divide the compound, the two halves are identical. Thus, it is **not optically active**.

#### Compound 2:
- Structure: Contains a chiral carbon with different substituents.
- Analysis: This compound has one chiral center and does not exhibit symmetry. Dividing it does not yield two equal halves. Thus, it is **optically active**.

#### Compound 3:
- Structure: Similar to Compound 2, with a benzene ring and substituents.
- Analysis: This compound has multiple chiral centers and does not exhibit symmetry. Dividing it does not yield equal halves. Thus, it is **optically active**.

#### Compound 4:
- Structure: Contains three chiral centers.
- Analysis: Although it has chiral centers, it exhibits symmetry. If we divide it, we get two equal halves. Thus, it is **not optically active**.

### Conclusion
From the analysis:
- **Optically Active Compounds**: Compound 2 and Compound 3.
- **Not Optically Active Compounds**: Compound 1 and Compound 4.

### Final Answer
The compounds that are optically active are **Compound 2 and Compound 3**.

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