反应详情

5.83 g of 3-amino-6-chloropyridazine was suspended in 70 ml of ethanol; 9.75 g of methyl 3-bromo-2-oxobutyrate and 8.6 ml of N-ethyldiisopropylamine were added, followed by thermal refluxing for 5 hours. After cooling, the mixture was concentrated under reduced pressure. The residue was adjusted to pH 7 by the addition of an aqueous solution of sodium hydrogen carbonate and extracted with ethyl acetate-tetrahydrofuran(1:1); the extract was washed with saline, dried over magnesium sulfate and concentrated under reduced pressure; ethyl acetate was added to the residue; the crystal precipitated was collected by filtration, washed with ethyl acetate and dried to yield 3.9 g of the title compound.

1. customrefluxing for 5 hours
2. temperatureAfter cooling
3. concentrationthe mixture was concentrated under reduced pressure
4. additionThe residue was adjusted to pH 7 by the addition of an aqueous solution of sodium hydrogen carbonate
5. extractionextracted with ethyl acetate-tetrahydrofuran(1:1)
6. washthe extract was washed with saline
7. dry with materialdried over magnesium sulfate
8. concentrationconcentrated under reduced pressure
9. additionethyl acetate was added to the residue
10. customthe crystal precipitated
11. filtrationwas collected by filtration
12. washwashed with ethyl acetate
13. customdried