反应详情

67.99 g (492 mmol) of potassium carbonate and 1.87 g (8.2 mmol) of benzyltriethylammonium chloride are suspended in 500 ml of acetonitrile. 59.86 g (410 mmol) of methyl 4-methoxyacetoacetate are added thereto while stirring. 65.50 g (615 mmol) of 1-chloro-2-butanone are added dropwise thereto within 30 minutes and the mixture is stirred at 20°-25° C. for 23 hours. The reaction mixture is poured into 1 l of 1N HCl (pH value=1) and extracted 3 times with 700 ml of ethyl acetate each time. The combined organic phases are dried over magnesium sulphate and concentrated on a rotary evaporator. The crude product distils at 115° C./0.05 mbar. There results 49.01 g (55.3%) of methyl 4-methoxy-2-(2-oxobutyl)-acetoacetate.

1. stirringthe mixture is stirred at 20°-25° C. for 23 hours
2. extractionextracted 3 times with 700 ml of ethyl acetate each time
3. dry with materialThe combined organic phases are dried over magnesium sulphate
4. concentrationconcentrated on a rotary evaporator
5. customThe crude product distils at 115° C./0.05 mbar