1.3 Aromatic Hydrocarbons (Benzene Rings)

• Benzene: alternating double bonds in a cyclohexane. Drawn as a circle inside a hexane.

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Naming Aromatic Compounds

1. Use the benzene ring as the parent chain

   1. “benzene” becomes the root

   2. other rules remain the same

      1. Use this method when the substituent is simple

2. Name the benzene ring as the substituent with the name “phenyl”

   1. Use this method when the substituent is complex

   

Special Cases

• Orthodimethylbenzene

• Metadimethylbenzene

• Paradimethylbenzene

  

Properties of Aromatic Hydrocarbons

• Liquids of crystalline solids at room temperature
• Non-polar
• Insoluble in water

Reactions of Aromatic Hydrocarbons

• Aromatic hydrocarbons unlike alkanes are unsaturated, but they undergo ^^substitution reactions like alkanes.^^
• This is because the bonds are not alternating single-double bonds like in the structural diagram, but ^^equal bonds in resonance.^^

Halogenation

Nitration

Alkylation

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