- Acylation
In
chemistry , acylation (rarely, but more formally: alkanoylation) is the process of adding anacyl group 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
electrophile when treated with some metalcatalyst s,acyl halide s are commonly used as acylating agents. For example, Friedel-Crafts acylation usesacetyl chloride (ethanoyl chloride), CH3COCl, as the agent and aluminum chloride (AlCl3) as a catalyst to add an ethanoyl(acetyl ) group tobenzene :
The mechanism of this reaction iselectrophilic substitution .Acyl halide s andanhydride s ofcarboxylic acid s are also commonly used acylating agents to acylateamine s to formamide s or acylatealcohol s to formester s. The amines and alcohols arenucleophiles ; the mechanism isnucleophilic addition-elimination.Succinic acid is 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 ofaspirin , in whichsalicylic acid is acylated byacetic anhydride .Mechanism of Friedel Crafts:
ee also
*
acetyl
*ketene
*indicator
*chemical synthesis References
* [http://crisp.cit.nih.gov/Thesaurus/00000094.htm NIH Thesaurus]
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