Phosphorus oxychloride → 2-Chloro-6,7-difluoro-3-styrylquinoxaline
Reaction equation
[F:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][C:11]=1[F:12])[NH:8][C:7](=O)[C:6]([CH:14]=[CH:15][C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1)=[N:5]2.O=P(Cl)(Cl)[Cl:24]>CN(C)C1C=CN=CC=1>[Cl:24][C:7]1[C:6]([CH:14]=[CH:15][C:16]2[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=2)=[N:5][C:4]2[C:9](=[CH:10][C:11]([F:12])=[C:2]([F:1])[CH:3]=2)[N:8]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
The above 6,7-difluoro-3-styryl-1H-quinoxalin-2-one (2.65 g, 0.93 mmol) was mixed with 4-dimethylaminopyridine (0.27 g) and POCl3 (27 ml) and the mixture was refluxed for 30 minutes. After cooling, the mixture was poured onto ice (400 ml) and the solid was filtered, washed with water (3×) and dried in vacuo overnight. Column chromatography on silica gel, eluting with ethyl acetate:heptane 1:20 afforded 1.6 g (56%) of the title compound.