Hydrogen Bromide → HCID 13745458, Verbindung
Reaktionsgleichung
[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][C:11]=1[F:12])[N:8]([C:13]1[CH:18]=[CH:17][C:16]([O:19]C)=[CH:15][CH:14]=1)[CH:7]=[C:6]([C:21]([O:23]CC)=[O:22])[C:5]2=[O:26].Br>>[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][C:11]=1[F:12])[N:8]([C:13]1[CH:14]=[CH:15][C:16]([OH:19])=[CH:17][CH:18]=1)[CH:7]=[C:6]([C:21]([OH:23])=[O:22])[C:5]2=[O:26]Komponenten
3
Versuchsvorschrift
To ethyl 6,7-difluoro-1-(4-methoxyphenyl)-1,4-dihydro-4-oxoquinoline-3-carboxylate (0.70 g) is added 48% hydrobromic acid (8 ml), and the mixture is stirred at 100°-110° C. for 3 hour. After cooling, the precipitated crystals are separated by filtration, washed with water and recrystallized from dichloromethane-ethanol to give 6,7-difluoro-1-(4-hydroxyphenyl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (0.57 g) as colorless needles, m.p. 288°-290° C.
Aufarbeitung
- temperatureAfter cooling
- customthe precipitated crystals are separated by filtration
- washwashed with water