Which of the following IUPAC name is not correctly matched?

Options

A.
B.
C.
D.

Answer

To determine which of the following IUPAC names is not correctly matched, we need to analyze each option based on the IUPAC naming conventions for organic compounds.

### Step-by-Step Solution:

1. **Identify the Compounds**: We need to look at the provided options and identify the structure of each compound based on its name.

2. **Analyze Option A**:
- The name is "cyclopentane".
- This indicates a cyclic compound with five carbon atoms.
- There are no double or triple bonds.
- **Conclusion**: The name "cyclopentane" is correctly matched.

3. **Analyze Option B**:
- The name is "1-chloro-cyclohexane".
- This indicates a cyclic compound with six carbon atoms and a chlorine substituent at the first carbon.
- **Conclusion**: The name "1-chloro-cyclohexane" is correctly matched.

4. **Analyze Option C**:
- The name is "1,1-dimethyl-ethyl".
- This suggests a compound with a main chain and two methyl groups attached to the first carbon of an ethyl group.
- However, the naming is incorrect because the correct way to name this compound should reflect the main chain and substituents properly.
- **Conclusion**: The name "1,1-dimethyl-ethyl" is not correctly matched.

5. **Analyze Option D**:
- The name is "3-nitro-cyclohexene".
- This indicates a cyclic compound with six carbon atoms and a double bond, along with a nitro group at the third carbon.
- The presence of the double bond is correctly indicated by the "ene" suffix.
- **Conclusion**: The name "3-nitro-cyclohexene" is correctly matched.

6. **Final Conclusion**:
- Based on the analysis, the only incorrectly matched name is **Option C** ("1,1-dimethyl-ethyl").

### Final Answer:
The IUPAC name that is not correctly matched is **Option C**.

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