17.21: How Chemists Activate Carboxylic Acids
- Page ID
- 16425
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Carboxylic acids react with Thionyl Chloride (\(SOCl_2\)) to form acid chlorides. During the reaction the hydroxyl group of the carboxylic acid is converted to a chlorosulfite intermediate making it a better leaving group. The chloride anion produced during the reaction acts a nucleophile.
General Reaction
Mechanism
1) Nucleophilic attack on Thionyl Chloride
2) Removal of Cl leaving group
3) Nucleophilic attack on the carbonyl
4) Leaving group removal
5) Deprotonation
Contributors
Prof. Steven Farmer (Sonoma State University)