Question

Among the following the aromatic compound(s) is/are:
A.
B. C.
D.

Choose the correct answer from the following options.

• A. (A) and (B) only
• B. (A), (B) and (C) only
• C. (B), (C) and (D) only
• D. (B) and (C) only

Answer 1

The correct option is D (B) and (C) only

According to Huckel rule, for a ring to be aromatic it should have the following properties:
a) Planarity
b) Complete delocalization of the π electrons in the ring
c) Presence of $(4n+2)\pi$ electrons in the ring where $n$ is an integer $(n=0,1,2,...)$

A-
Here $\pi$ electrons are not conjugated. So it is non-aromatic.

B-

It is cyclic, planar and have $6\pi$ conjugated electrons. So, it is aromatic.

C-

It is cyclic, planar and have $6\pi$ conjugated electrons. So, it is aromatic.

D-

It is cyclic, planar and has $4\pi$ electrons in conjugation.It is an anti-aromatic compound.