Alkylation introduces an alkyl group into a molecule. The new group may attach to carbon, nitrogen, oxygen, sulfur, or another suitable atom; the name alone does not specify the mechanism.
For example, an alkoxide can react with a suitable alkyl halide to form an ether by nucleophilic substitution, while Friedel-Crafts alkylation attaches an alkyl group to an aromatic ring through an electrophilic pathway. Competing elimination, multiple substitution, or rearrangement depends on the particular reacting partners.
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