6.1.2

• Substitution reaction Where a group of atom is exchanged by another in a chemical reaction benzene derivative a benzene that has undergone substitution As benzene has delocalised electrons:

  • rarely undergoes addition reactions but commonly substitution

  → H atom is substituted for another group and a benzene derivative is formed (monosubstitution)
• • Where a group of atom is exchanged by another in a chemical reaction
  • benzene derivative is a benzene that has undergone substitution As benzene has delocalised electrons:
  • • rarely undergoes addition reactions but commonly substitution → H atom is substituted for another group and a benzene derivative is formed (monosubstitution)
• Double substituted Benzene Derivative (di substituted) when 2 hydrogen atoms are substituted by another atom or group + a benzene derivative is formed can also be substituted by multiple
• cyclohexene hydrogenation

  
• cyclo-1,3,5-hexatriene hydrogenation