question_answer

The total number of aromatic species generated in the following reactions is

(i)

(ii)

(iii)

(iv)

A)  zero    

B)  2       

C)  3       

D)  4

Correct Answer: C

Solution :

 Criteria for aromaticity (Huckel rule) The cyclic\[\pi \]molecular orbital (electron cloud) formed by overlap of p-orbitals must contain \[(4n+2)\pi -\]electrons, where n = integer 0, 1, 2, 3, etc. This is known as Huckel rule. (i) (ii) (iii) (iv)