1. Non benzenoid aromatic compounds
1. Azulene

2. 2-chorotroplone

2. Aromatic heterocyclic compounds
1.Pyroll

2.Furan

3. Alicyclic compounds
1. Cyclopentane

2. Cyclohexane

4. Aliphatic open chain compounds
- CH3-CH2-CH2-CH2-CH3 n-pentane
- CH3 -CH2 -CH2OH 1-propanol