反应详情

温度

175 °C

92.8 g of diethyl 2-butyrylsuccinate and 23.5 g of boric acid were heated to 150° C. in a round flask with distillation head piece, whereby ethanol distilled off. The mixture was subsequently heated to 175° C. and stirred at this temperature for 4 hours (evolution of carbon dioxide). After completion of the reaction, the mixture was cooled to room temperature, taken up in 500 ml of hexane and washed with 150 ml of 5% (wt./vol.) sodium hydrogen carbonate solution and 100 ml of water. The aqueous phases were back-extracted with 50 ml of hexane. The combined organic phases were dried over sodium sulphate and freed from solvent on a rotary evaporator. Distillation of the resulting crude product in a high vacuum over a Vigreux column gave in the main run 58.6 g (89.6%) of ethyl 4-oxoheptanoate as a colourless liquid; b.p. 50°-56° C./0.2 Torr.

1. distillationdistilled off
2. customAfter completion of the reaction
3. temperaturethe mixture was cooled to room temperature
4. washwashed with 150 ml of 5% (wt./vol.) sodium hydrogen carbonate solution and 100 ml of water
5. extractionThe aqueous phases were back-extracted with 50 ml of hexane
6. dry with materialThe combined organic phases were dried over sodium sulphate
7. customfreed from solvent on a rotary evaporator
8. distillationDistillation of the resulting crude product in a high vacuum over a Vigreux column