Explain why the following systems are not aromatic?

Question

Philoid · Accepted Answer

For the given compound, the number of π-electrons is 6.

By Huckel’s rule,

4n + 2 = 6

⇒ 4n = 4

⇒ n = 1

For a compound to be aromatic, the value of n must be an integer (n = 0, 1, 2…).

In this case, the value of n is 1 which is an integer, hence the given compound is aromatic in nature.