Explain why the following systems are not aromatic?

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.


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