反应详情

At room temperature, to a mixture of 1-(4-methoxy-3-methylphenyl)-ethanone (described in Reference Preparation example 48) and tetrahydrofuran 200 ml was added diethyl carbonate 16.1 g, 55% sodium hydride 6.2 g, dibenzo-18-crown-6 0.05 g and ethanol 3 mL, and the resulting mixture was stirred with heating under reflux for eight hours. To the reaction mixture was added water, and the resulting mixture was acidified with 10% aqueous hydrochloric acid solution and was extracted with ethyl acetate. The organic layer was washed with water and was dried over anhydrous magnesium sulfate, and was then concentrated under reduced pressure. The resulting residue was subjected to a silica gel column chromatography to give 3-(4-methoxy-3-methyl-phenyl)-3-oxo-propionic acid ethyl ester 14.8 g.

1. temperaturewith heating
2. temperatureunder reflux for eight hours
3. extractionwas extracted with ethyl acetate
4. washThe organic layer was washed with water
5. dry with materialwas dried over anhydrous magnesium sulfate
6. concentrationwas then concentrated under reduced pressure