Page 164 - Pharm.Org.Chem-I 02-06-05-101

4) Friedel-Crafts Alkylation

Mechanism:

Step 1

Step 2 H3C
CH3
H3C CH3
CH

CH3 AlCl4- + HCl + AlCl3

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Limitations of Friedel-Crafts alkylation
1- Rearrangement of carbocation
In FC alkylation, the alkyl carbocation may rearrange to a more stable carbocation
and the major products obtained are those from the more stable carbocations.

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