Question

Which of the followig is aromatic?
A. `[18]`-annulene
B. `[16]`-annlene
C. `[14]`-annulene
D. `[10]`-annulene

Answer 1

Correct Answer - 1
According to the Huckel rule, the `[14],[18]` and `[22]` annulenes `(4n+2` where `n=3,4,5`, respectively have been found to be aromatic `[12],[16] and [24]` annulenes are not aromatic. They are 4n compounds not `4n+2` compounds `[10]` annulenes are expected to be aromatic on the basis of `e^(-)` count, but they are not aromatic as their rings are not planar.