反应详情

温度

-30 °C

4 Grams of 60% sodium hydride was suspended in 150 ml of anhydrous dimethoxyethane and the suspension was cooled to -30° C. Then, 19.4 g of methyl 4-bromoacetoacetate was added dropwise to the suspension and stirred for 1 hour. Further, at the same temperature, an anhydrous dimethoxyethane solution of sodium cinnamy alcoholate prepared from 13.4 g of cinnamyl alcohol, 4 g of 60% of sodium hydride and 75 ml of dimethoxyethane was added dropwise thereto, and the reaction mixture was refluxed for 15 hours. After the reaction mixture was cooled to a room temperature, the reaction mixture was poured into 1N-hydrochloric acid being ice-cooled, and the whole mixture was extracted with ether. The ether extract was washed with water and dried with anhydrous sodium sulfate, and the solvent was removed by evaporation. The residue was purified by means of a silica gel column chromatography (eluent: methanol:dichloromethane=1:20) to yield 6 g of methyl 4(E)-cinnamyloxyacetoacetate Refractive index: nD20 1.5402

1. additionwas added dropwise
2. temperaturethe reaction mixture was refluxed for 15 hours
3. temperatureAfter the reaction mixture was cooled to a room temperature
4. temperaturecooled
5. extractionthe whole mixture was extracted with ether
6. extractionThe ether extract
7. washwas washed with water
8. dry with materialdried with anhydrous sodium sulfate
9. customthe solvent was removed by evaporation
10. customThe residue was purified by means of a silica gel column chromatography (eluent: methanol:dichloromethane=1:20)