Ncert Exercises & Solutions

Which of the following compounds are aromatic according to Huckekl's rule?

A. The compound has

8 π

electrons. It will be non-aromatic. Both rings are non-benzenoid.

B. The compound is aromatic. It has

6 {πe}^{-}

delocalised electron (

4 {πe}^{-} + 2

lone pair electrons), all the four carbon atoms and the N atom are sp² hybridised.

C. The compound contains

6 π

electrons but not in the ring hence it is non-aromatic.

10 {πe}^{-}

obeying Huckel rule and the ring is planar. It is aromatic.

E. In this compound one six membered planar ring has

6 {πe}^{-}

although it has

8 π

electrons in two rings. It is therefore aromatic.

F. It has

14 π

electrons in conjugation and in the planar ring, Huckel rule is verified. It will be aromatic.