反应详情

16.58 g (120 mmol) of potassium carbonate and 0.46 g (2 mmol) of benzyltriethylammonium chloride are suspended in 50 ml of acetonitrile. While stirring there are added thereto 14.60 g (100 mmol) of methyl 4-methoxyacetoacetate and there are added dropwise thereto within 10 minutes 15.97 g (150 mmol) of 3-chloro-2-butanone. The mixture is stirred at 20°-25° C. for a further 65 hours. The reaction mixture is poured on to 70 ml of 4N HCl/ice (pH value=1) and extracted 3 times with 100 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 95° C./0.05 mbar and gives 6.67 g (42%) of methyl 4-methoxy-2-[1-methylacetonyl]-acetoacetate.

1. additionare added
2. stirringThe mixture is stirred at 20°-25° C. for a further 65 hours
3. extractionextracted 3 times with 100 ml of ethyl acetate each time
4. dry with materialThe combined organic phases are dried over magnesium sulphate
5. concentrationconcentrated on a rotary evaporator
6. customThe crude product distils at 95° C./0.05 mbar