chemistry, acylation (rarely, but more formally: alkanoylation) is the process of adding an acylgroup to a compound. The compound providing the acyl group is called the acylating agent. These are used to form aryl ketones.
Because they form a strong
electrophilewhen treated with some metal catalysts, acyl halides are commonly used as acylating agents. For example, Friedel-Crafts acylation uses acetyl chloride(ethanoyl chloride), CH3COCl, as the agent and aluminum chloride (AlCl3) as a catalyst to add an ethanoyl( acetyl) group to benzene:
The mechanism of this reaction is
electrophilic substitution. Acyl halides and anhydrides of carboxylic acids are also commonly used acylating agents to acylate amines to form amides or acylate alcohols to form esters. The amines and alcohols are nucleophiles; the mechanism is nucleophilicaddition-elimination. Succinic acidis also commonly used in a specific type of acylation called "succination". "Oversuccination" occurs when more than one succinate adds to a single compound. An industrial example of acylation in the synthesis of aspirin, in which salicylic acidis acylated by acetic anhydride.
Mechanism of Friedel Crafts:
* [http://crisp.cit.nih.gov/Thesaurus/00000094.htm NIH Thesaurus]
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