Aromatic compound

Aromatic compounds are compounds containing a planar set of atoms that are (in the classical sense) connected by single and double bonds alternating in a system of one or more closed rings. The most famous such compound is benzene.

In modern terminology, they can be described as compounds in which a continuous, closed system of rings contains separate sets of sigma and pi electrons. The atomic orbitals forming the sigma system are sp² hybridized[?], and those forming the pi system are pure p orbitals. The Hückel "4n+2" rule can be used to predict when aromatic behavior exists.

Properties Of Aromatic Compounds

1. They have closed congugation.
2. The Carbon Atoms are sp² Hybrid,and have a planar structure.
3. The Carbon-Hydrogen ratio is very small.
4. They burn with a yellow sooty flame because of the low carbon-hydrogen ratio.
5. They Undergo Electrophilic substitution reactions unlike Aliphatic Compounds which undergo Nucleophilic substitution reactions.