Friedel–Crafts Reaction
The introduction of an alkyl or acyl group onto an aromatic ring using a Lewis acid catalyst.
Formula / equation
ArH + RCl + AlCl₃ → ArR + HCl
Unit
Dimensionless
In depth
The aluminium chloride abstracts chloride to generate a carbocation or acylium electrophile. Alkylation suffers from rearrangement and polysubstitution because the product is more reactive than the starting material; acylation avoids both, and the ketone can then be reduced.
Examples in the real world
Benzene with chloromethane and AlCl₃ giving toluene; acylation giving acetophenone.