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The Dakin–West reaction is a chemical reaction that transforms an amino-acid into a keto-amide using an acid anhydride and a base, typically pyridine. It is named for Henry Drysdale Dakin (1880–1952) and Randolph West (1890–1949). Of special note, the keto-amide product is always racemic. With pyridine as a base and solvent, refluxing conditions are required. However, with the addition of 4-dimethylaminopyridine (DMAP) as a catalyst, the reaction can take place at room temperature. With some acids, this reaction can take place even in the absence of an α-amino group. This reaction should not be confused with the Dakin reaction. ==Reaction mechanism== The reaction mechanism involves the acylation and activation of the acid 1 to the mixed anhydride 3. The amide will serve as a nucleophile for the cyclization forming the azlactone 4. Deprotonation and acylation of the azlactone forms the key carbon-carbon bond. Subsequent ring-opening of 6 and decarboxylation give the final keto-amide product. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dakin–West reaction」の詳細全文を読む スポンサード リンク
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