Question

5. Indicate if each of the following compounds is aromatic or not. H H

Answer 1

Aromatic compounds are highly unsaturated, cyclic molecules that show extra stability as compared to their open chain counterpart.

Huckel's rule for aromaticity states that a molecule must meet all of the following four conditions in order to be aromatic:

1) cyclic -- the molecule must be a cyclic polyene;
2) planar -- the geometry of the cyclic part must be planar;
3) each atom in the cyclic system must have a p orbital perpendicular to the ring;
4) the cyclic system has 4n+2 pi electrons

I H N :0: N

Both compounds contains 6 pi electrons , conjugated double bonds and cyclic. so both compounds are aromatic