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The Tishchenko reaction is an organic chemical reaction that involves disproportionation of an aldehyde lacking a hydrogen atom in the alpha position in the presence of an alkoxide. The reaction product is an ester. Catalysts are aluminium alkoxides or sodium alkoxides. In the related Cannizzaro reaction the base is sodium hydroxide and then the oxidation product is a carboxylic acid and the reduction product is an alcohol. == Examples == * Benzaldehyde reacts with sodium benzyloxide (generated from sodium and benzyl alcohol) to generate benzyl benzoate. * The Tishchenko reaction of acetaldehyde gives the commercially important solvent ethyl acetate; it is catalyzed by aluminium alcoholate. * The Tishchenko reaction is used to obtain isobutyl isobutyrate, a specialty solvent. * Hydroxypivalic acid neopentyl glycol ester is produced by a Tishchenko reaction from hydroxypivaldehyde in the presence of a basic catalyst (e.g., aluminium oxide). * The Tishchenko reaction of paraformaldehyde in the presence of aluminum methylate or magnesium methylate forms methyl formate. * Paraformaldehyde reacts with boric acid to form methyl formate. The key step in the reaction mechanism for this reaction is a 1,3-hydride shift in the hemiacetal intermediate formed from two successive nucleophilic addition reactions, the first one from the catalyst. The hydride shift regenerates the alkoxide catalyst. 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「Tishchenko reaction」の詳細全文を読む スポンサード リンク
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