The non-aromatic compound among the following is

Options

A.
B.
C.
D.

Answer

To determine the non-aromatic compound among the given options, we need to analyze each compound based on the criteria for aromaticity. Aromatic compounds must be cyclic, planar, fully conjugated (having a continuous overlap of p-orbitals), and must follow Huckel's rule, which states that they must have \(4n + 2\) π electrons (where \(n\) is a non-negative integer).

### Step-by-Step Solution:

1. **Analyze Option A:**
- Check if the compound is cyclic and conjugated.
- Option A is not a conjugated system; it lacks the necessary continuous overlap of p-orbitals.
- Therefore, Option A does not meet the criteria for aromaticity and is the non-aromatic compound.

2. **Analyze Option B:**
- Check if the compound is cyclic and conjugated.
- Option B has a cyclic structure and is fully conjugated.
- It has 5 π electrons (which is an odd number), satisfying Huckel's rule (\(4n + 2\) where \(n=1\)).
- Therefore, Option B is aromatic.

3. **Analyze Option C:**
- Check if the compound is cyclic and conjugated.
- Option C has a cyclic structure and is fully conjugated, with a lone pair of sulfur contributing to the conjugation.
- It has 6 π electrons (3 pairs), satisfying Huckel's rule (\(4n + 2\) where \(n=1\)).
- Therefore, Option C is aromatic.

4. **Analyze Option D:**
- Check if the compound is cyclic and conjugated.
- Option D has a cyclic structure and is fully conjugated, with a negative charge contributing to the conjugation.
- It has 6 π electrons (3 pairs), satisfying Huckel's rule (\(4n + 2\) where \(n=1\)).
- Therefore, Option D is aromatic.

### Conclusion:
After analyzing all options, we find that:
- **Option A** is the non-aromatic compound.