反应详情

To 150 ml of ethanol containing 3.4 g of sodium was added dropwise 31 g of diethyl acetonylsuccinate (or diethyl acetmethylsuccinate) over about one hour with stirring at ambient temperature. The mixture was heated under reflux for 2 hours and then cooled to room temperature, followed by distillation off of the ethanol under reduced pressure. There was thus obtained a brown viscous liquid comprising sodium salt of ethyl 3,5-dioxocyclohexanecarboxylate as formed, to which were added 100 ml of toluene, 50 ml of ice water and 0.3 g of γ-picoline and then added dropwise 15 g of n-butyryl chloride at ambient temperature under agitation over about 2 hours. The resultant reaction mixture was agitated for further 30 minutes and then the toluene layer was separated, washed with water, dried and admixed with 0.8 g of 4-N,N-dimethylaminopyridine. The admixture was heated with agitation at a temperature of 80°-90° C. for 3 hours. The toluene was then distilled off from the reaction solution under reduced pressure and the residue was chromatographed on a column of silica gel developed with benzene to give 19.5 g (55.9%) of the object compound (Compound No. 15).

1. temperatureThe mixture was heated
2. temperatureunder reflux for 2 hours
3. temperaturecooled to room temperature
4. distillationfollowed by distillation off of the ethanol under reduced pressure