反应详情

温度

60 °C

To a solution of 100 g (0.77 mol) of ethyl acetoacetate in 500 ml of DMF 30.7 g (0.77 mol) of 60% suspension of NaH in mineral oil was added in small portions by vigorous stirring at 60° C. This mixture was additionally stirred for 1 h, and then 105.5 g (0.77 mol) of isobutylbromide was added. The resulting mixture was stirred for 3 h at 90° C., then cooled to room temperature, and 1500 ml of cold water was added. The product was extracted by 3×300 ml of dichloromethane. The combined organic extract was evaporated at reduced pressure using rotary evaporator. Fractional rectification of the residue gave the title product, b.p. 75-80° C./4 mm Hg. Yield 80.5 g (56%).

1. stirringThis mixture was additionally stirred for 1 h
2. stirringThe resulting mixture was stirred for 3 h at 90° C.
3. temperaturecooled to room temperature
4. extractionThe product was extracted by 3×300 ml of dichloromethane
5. extractionThe combined organic extract
6. customwas evaporated at reduced pressure
7. customevaporator