反应详情

温度

160 °C

A mixture of 1.5 g of 6-fluoro-5-chloro-1,2,3,4-tetrahydroquinaldine and 1.8 g of diethyl ethoxymethylenemalonate was heated at 160° C. for 30 minutes. Then, 14 g of polyphosphoric acid prepared from 7 g of phosphorus pentoxide and 7 g of phosphoric acid was added to the mixture and the resulting mixture was allowed to react by heating at 140° to 150° C. for 1 hour. After completion of the reaction, the reaction mixture was poured onto 100 g of ice, followed by adjusting the mixture to pH 6 to 7 with a 10 N aqueous sodium hydroxide solution. The precipitates were collected by filtration and added to 30 ml of concentrated hydrochloric acid followed by heating under reflux. After completion of the reaction 50 ml of water was added to the reaction mixture to precipitate crystals. The crystals thus-obtained were collected by filtration, washed with water and dried. Recrystallization of the crude crystals from ethanol gave 1.2 g of 9-fluoro-8-chloro-5-methyl-6,7-dihydro-1-oxo-1H,5H-benzo[ij]quinolizine-2-carboxylic acid as white rhombic crystals having a melting point of 297° to 298° C.

1. additionwas added to the mixture
2. customto react
3. temperatureby heating at 140° to 150° C. for 1 hour
4. customAfter completion of the reaction
5. filtrationThe precipitates were collected by filtration
6. additionadded to 30 ml of concentrated hydrochloric acid
7. temperatureby heating
8. temperatureunder reflux
9. customAfter completion of the reaction 50 ml of water
10. additionwas added to the reaction mixture
11. customto precipitate crystals
12. customThe crystals thus-obtained
13. filtrationwere collected by filtration
14. washwashed with water
15. customdried
16. customRecrystallization of the crude crystals from ethanol