[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][C:11]=1[Cl:12])[NH:8][C:7](=[O:13])[C:6]([CH3:14])=[N:5]2.S(=O)(=O)(O)O.[F:20][C:21]1[CH:28]=[CH:27][C:24]([CH:25]=O)=[CH:23][CH:22]=1>CC(OCC1C2C(=CC=CC=2)C(COC(C)=O)=C2C=1C=CC=C2)=O>[Cl:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][C:11]=1[Cl:12])[NH:8][C:7](=[O:13])[C:6]([CH:14]=[CH:25][C:24]1[CH:27]=[CH:28][C:21]([F:20])=[CH:22][CH:23]=1)=[N:5]26,7-Dichloro-3-methyl-1H-quinoxalin-2-one (5 g, 22 mmol) (prepared as described in: Collins, J. L.; Dambek, P. J.; Goldstein, S. W.; Faraci, W. S. Bioorg. Med. Chem. Lett. 1992, 2, 915-8) was dissolved in a mixture of glacial acetic add (100 ml) and 98% sulfuric acid (10 ml). 4-Fluorobenzaldehyde (2.3 ml, 22 mmol) was added and the resulting mixture was stirred at reflux temperature for 3.5 hours. The mixture was allowed to cool to 85° C. and then poured onto ice (500 ml). The solid was filtered, washed with water and ethyl acetate and dried in vacuo at 30° C. overnight to afford 7.2 g (99%) of 6,7-dichloro-3-[2-(4-fluorophenyl)vinyl]-1H-quinoxalin-2-one.
Wird geladen…
