反应详情

温度

70 °C

113.4 g (2.1 mmol) of sodium methylate are suspended in 150 ml of acetonitrile. 150.5 g (1 mol) of methyl 4-chloroacetoacetate are thereupon allowed to flow in within 5 minutes. The temperature rises, but it is held at 68°-70° C. by cooling. The mixture is subsequently stirred at 70° C. for a further 25 minutes. The reaction mixture is poured into a solution of 350 ml of distilled water and 9 g of acetic acid and held at a pH value of 6-7 by the addition of a total of 83 ml of 32% hydrochloric acid. The organic layer is separated in a separating funnel and the aqueous layer is extracted 3 times with 200 ml of acetonitrile each time. The combined organic phases are dried over magnesium sulphate and concentrated on a rotary evaporator. The crude product distils at 55°-57° C./0.6 mbar. There are obtained 132.34 g (90.6 %) of methyl 4-methoxy-acetoacetate.

1. customto flow in within 5 minutes
2. customis held at 68°-70° C.
3. temperatureby cooling
4. customThe organic layer is separated in a separating funnel
5. extractionthe aqueous layer is extracted 3 times with 200 ml of acetonitrile each time
6. dry with materialThe combined organic phases are dried over magnesium sulphate
7. concentrationconcentrated on a rotary evaporator
8. customThe crude product distils at 55°-57° C./0.6 mbar