反应详情

温度

5 °C

A powerful stream of hydrogen chloride gas is passed for 15 minutes into a solution of 230 ml of methyl acetate and 6.4 ml of methanol, at 0° C. to 10° C. 23.8 g of 2-cyanomethyl-4,6-dimethoxypyrimidine in 250 ml of methyl acetate are now added dropwise while more hydrogen chloride is passed in, and the passing-in of gas is stopped when the dropwise addition is complete, and stirring is continued for 5 hours at 10° C. to 15° C. 200 ml of absolute diethyl ether are added, the mixture is cooled to 5° C., and the precipitate is filtered off with suction under nitrogen. The residue is washed with ether and filtered off with suction until dry. This gives 31.5 g of the imidomethyl ester hydrochloride of melting point 110°-112° C., to which 250 ml of water are added, and the mixture is stirred for 4 hours at 40° C. The mixture is cooled to room temperature and extracted four times using four 150 ml portions of diethyl ether. The organic phase is dried over magnesium sulfate, and the solvent is distilled off. This gives 19.5 g of methyl (4,6-dimethoxypyrimidin-2-yl)acetate of boiling point 110° C./0.04 mbar (ball tube distillation).

1. additionthe dropwise addition
2. filtrationthe precipitate is filtered off with suction under nitrogen
3. washThe residue is washed with ether
4. filtrationfiltered off with suction
5. customuntil dry
6. additionThis gives 31.5 g of the imidomethyl ester hydrochloride of melting point 110°-112° C., to which 250 ml of water are added
7. stirringthe mixture is stirred for 4 hours at 40° C
8. temperatureThe mixture is cooled to room temperature
9. extractionextracted four times
10. dry with materialThe organic phase is dried over magnesium sulfate
11. distillationthe solvent is distilled off
12. distillationThis gives 19.5 g of methyl (4,6-dimethoxypyrimidin-2-yl)acetate of boiling point 110° C./0.04 mbar (ball tube distillation)