反应详情

温度

70 °C

A suspension of 2 g of ethyl 8,9-difluoro-4-methyl-1-oxo-1,4-dihydrobenzo[f][1,7]naphthyridine-2-carboxylate and 1.1 g of pyrrolidine in 40 cm3 of dimethylformamide was heated, with stirring, at a temperature of 70° C. for 8 hours. After cooling to 20° C., the mixture was poured into 150 cm3 of ice-cold water. The insoluble material was dewatered, washed 3 times with 30 cm3 of water, and dissolved in 300 cm3 of dichloromethane; the residual water was decanted off. The organic extracts were dried over sodium sulphate; after filtration and concentration under reduced pressure (5.2 kPa), the compound obtained was purified by chromatography on 180 g of silica gel (0.06-0.20 mm). Elution was carried out with 3.6 liters of a dichloromethane-ethanol mixture (97-3 by volume) and with 6 liters of a dichloromethane-ethanol mixture (94-6 by volume), 150 cm3 fractions were collected. The fractions obtained from the latter mixture were concentrated to dryness under reduced pressure. 0.85 g of ethyl 9-fluoro-4-methyl-1-oxo-8-pyrrolidinyl-1,4-dihydrobenzo[f][1,7]naphthyridine-2-carboxylate was obtained in the form of a yellow compound, which melted at 270° C.

1. temperaturewas heated
2. temperatureAfter cooling to 20° C.
3. washwashed 3 times with 30 cm3 of water
4. dissolutiondissolved in 300 cm3 of dichloromethane
5. customthe residual water was decanted off
6. dry with materialThe organic extracts were dried over sodium sulphate
7. filtrationafter filtration and concentration under reduced pressure (5.2 kPa)
8. customthe compound obtained
9. customwas purified by chromatography on 180 g of silica gel (0.06-0.20 mm)
10. washElution
11. customwere collected
12. customThe fractions obtained from the latter mixture
13. concentrationwere concentrated to dryness under reduced pressure