halogenation of benzene Flashcards
1
Q
why is no heating required?
A
exothermic nature of reaction keeps it going
2
Q
what catalyst is required in halogenation?
A
AlCl3 or FeCl3
3
Q
how is an electrophile formed in halogenation?
A
AlCl3 + Cl2 –> AlCl4- + Cl+
4
Q
describe the electrophilic attack in halogenation
A
- Cl+ accepts electron from pi cloud so arrow out to ion
- benzene becomes positive
- cloud only covers 4 sides of ring
- H loses electron to reform cloud
- produces chlorobenzene and H+
5
Q
how is the catalyst reformed in halogenation?
A
AlCl4- + H+ –> AlCl3 + HCl
