| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing an α-ketocarboxylic acid ester by oxidizing a specific α-hydroxycarboxylic acid ester with hypochlorous acid in the presence of a specified hindered secondary amine under an acidic condition, capable of producing the α-ketocarboxylic acid ester from the general chemical agents in a high yield under as mild conditions as possible. SOLUTION: The method for producing an α-ketocarboxylic acid ester comprises oxidizing an α-ketocarboxylic acid ester of formula I [R<1> is an alkyl, a cycloalkyl, a (substituted) aryl or an aralkyl; R<2> is a 1-4C alkyl] (for example, methyl lactate or ethyl lactate) with hypochlorous acid in the presence of a hindered secondary amine of formula II (R<3> is H, a <=18C alkyl, a <=18C alkoxy or a <=18C acyloxy) or formula III [(n) is 4-10] [for example, bis(2,2,6,6- tetramethyl-4-piperidyl)sebacate] in a water-immiscible solvent (for example, a halogenated hydrocarbon such as dichloromethane or an aliphatic acid ester such as ethyl acetate) under an acidic condition having a pH of <=6, preferably <=5. |
