Electrophilic aromatic substitution – Friedel-Crafts alkylation

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Friedel-Crafts alkylation usually involves treating benzene with a secondary or tertiary alkyl halide, and the Lewis acid AlCl3. In this example, the Lewis acid removes the chloride atom from the t-BuCl, which then releases the t-Bu cation for the alkylation reaction. Chloride then removes the proton from the cationic intermediate restoring aromaticity.

G. A. Olah, Acc. Chem. Res., 1971, 4, 240–248.


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