Isomers which can be interconverted through rotation around a single bond are

Options

A. Conformers
B. Diastereomers
C. Chain isomers
D. Positional isomers

Answer

To solve the question about isomers that can be interconverted through rotation around a single bond, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Isomers**:
- Isomers are compounds that have the same molecular formula but different structural arrangements. They can be classified into different types based on their structural differences.

2. **Types of Isomers**:
- The question provides four types of isomers: quantumers, diastereomers, chain isomers, and positional isomers. We need to analyze these types to determine which can be interconverted through rotation around a single bond.

3. **Conformers**:
- The isomers that can be interconverted by rotation around a single bond are known as **conformers** (or conformational isomers). These are different spatial arrangements of the same molecule that can be converted into one another by rotation around sigma (σ) bonds.

4. **Energy Requirement**:
- The rotation around a single bond requires a small amount of energy, which is typically available at room temperature. This allows the molecule to adopt different conformations easily.

5. **Exclusion of Other Isomers**:
- **Diastereomers**: These are stereoisomers that are not mirror images of each other and cannot be interconverted by rotation around a single bond.
- **Chain Isomers**: These involve different arrangements of the carbon skeleton (e.g., straight-chain vs. branched-chain) and do not involve rotation around a single bond.
- **Positional Isomers**: These differ in the position of a functional group on the same carbon chain and also do not involve rotation around a single bond.

6. **Conclusion**:
- Therefore, the correct answer to the question is that the isomers which can be interconverted through rotation around a single bond are **conformers**.

### Final Answer:
The isomers which can be interconverted through rotation around a single bond are **conformers**.