反应详情

A solution of 0.76 g (2.00 mmol) of ethyl 6,7-difluoro-1-(2,4-difluorophenyl)-1,4-dihydro-5-methyl-4-oxo-3-quinolinecarboxylate, 0.69 g (8.00 mmol) of anhydrous piperazine, and 30 mL of acetonitrile was refluxed for 18 hours, cooled, and concentrated. The residue was dissolved in 20 mL 6N hydrochloric acid and refluxed for 3 hours. The suspension was cooled, concentrated by half and filtered, and the solids were washed with water. The crude product was suspended in water which was made basic (pH 12), and the resulting solution was filtered and neutralized to pH 6.8. The precipitate which formed was filtered, washed with water, and dried to give 0.58 g of the title compound, mp 198°-200° C.

1. temperaturecooled
2. concentrationconcentrated
3. dissolutionThe residue was dissolved in 20 mL 6N hydrochloric acid
4. temperaturerefluxed for 3 hours
5. temperatureThe suspension was cooled
6. concentrationconcentrated by half
7. filtrationfiltered
8. washthe solids were washed with water
9. filtrationthe resulting solution was filtered
10. customThe precipitate which formed
11. filtrationwas filtered
12. washwashed with water
13. customdried