Friedel-Crafts alkylation and acylation (electrophilic aromatic substitution) (Arene + alkyl chloride + Lewis acid → alkylation; acyl chloride gives ketone (acylation).)

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Arene + alkyl chloride + Lewis acid → alkylation; acyl chloride gives ketone (acylation). Electrophile attacks ring; regeneration issues with alkylation.

What each symbol means

SymbolWhat it stands for
AlCl3Lewis acid generates R+ or acylium RCO+ equivalent
ProductAlkylation may rearrange carbocation; polyalkylation possible

When to use this

Anhydrous. Strongly deactivated rings (–NO2 etc.) often fail. Acylation avoids rearrangement; cleavage of ketone product possible later.