Question

Among the following organic compounds, the one that is non‐aromatic is:

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is D

To determine which compound among the given options is non-aromatic, we need to consider the criteria for aromaticity. The criteria are as follows:

• The compound must be cyclic.
• The compound must be planar.
• The compound must have a conjugated system of pi electrons.
• The compound must follow Huckel's rule, which states there must be \(4n + 2\) pi electrons, where \(n\) is a non-negative integer.

Let's analyze each given option based on these criteria: 

This compound is cyclic, planar, and has conjugated pi electrons. It satisfies Huckel's rule.

This compound is also cyclic, planar, and has a conjugated pi electron system satisfying Huckel's rule.

Like the previous ones, this compound meets all the criteria for aromaticity, including Huckel's rule.

This compound does not satisfy the criteria for aromaticity. In particular, it does not meet Huckel's rule for the number of pi electrons necessary for aromaticity.

Thus, the compound in option 4 is non-aromatic, as it cannot satisfy all the necessary conditions for aromaticity.

Conclusion: The correct answer is the compound represented by option 4.