Page 156 - Pharm.Org.Chem-I 02-06-05-101

Examples on Hückel’s Rule 4n + 2 = π es

3- Anthracene 1- Planar
2- sp2 hybridized
3- continuous resonance ∴ AROMATIC
4- Obey Huckel’s rule

4n+2 = 14 electrons
4n = 12
n=3

4- Cyclopenta-1,3-diene

HH 1- Planar ∴ NON AROMATIC
2- one sp3 carbon
3- no continuous resonance 4n+2 = 4 electrons
4n = 2
4- doesn’t obey Huckel’s rule n = 1/2

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Aromatic hydrocarbons
Nomenclature of Arenes (Aromatic hydrocarbons)

I- Monosubstituted compounds:

If benzene is the parent compound, so the substituent is put as prefix.

Chlorobenzene Nitrobenzene Methylbenzene Hydroxybenzene Methoxybenzene

(Toluene) (Phenol) (Anisole)

Benzoic acid Aminobenzene Vinylbenzene Acetophenone
(Aniline)
(Styrene)

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