Which one of the following compound is nonaromatic?

Question

Quizplus · Accepted Answer

According to Hückel's rule, a compound must have 4n+2 π electrons to be aromatic. In compound I, there are 10 π electrons which follow this rule so it is aromatic. In compound II, there are only 8 π electrons so it is nonaromatic. In compound III, there are 14 π electrons which follow this rule so it is aromatic. In compound IV, there are 12 π electrons which do not follow this rule so it is nonaromatic. Therefore, the only nonaromatic compound is II or choice B.

Which One of the Following Compound Is Nonaromatic