Phosphorus oxychloride → 2-Chloro-3-fluoro-7-methoxyquinoline
Reaction equation
[F:1][C:2]1[C:3](=O)[NH:4][C:5]2[C:10]([CH:11]=1)=[CH:9][CH:8]=[C:7]([O:12][CH3:13])[CH:6]=2.O=P(Cl)(Cl)[Cl:17]>>[Cl:17][C:3]1[C:2]([F:1])=[CH:11][C:10]2[C:5](=[CH:6][C:7]([O:12][CH3:13])=[CH:8][CH:9]=2)[N:4]=1Participants
3
Procedure
A mixture of 3-fluoro-7-methoxyquinolin-2(1H)-one (1.40 g, 7.25 mmol) and POCl3 (13.3 ml, 145 mmol) was stirred at 110 C (bath) for 1 hour. The POCl3 was removed under reduced pressure. Ethyl acetate (30 mL) and saturated sodium bicarbonate (30 mL) were added and stirred for 10 minutes. The organic layer was separated, washed with brine, dried (sodium sulfate), filtered and concentrated under reduced pressure. The crude residue was purified by flash chromatography on silica gel (10:1 hexane/ethyl acetate) to give 2-chloro-3-fluoro-7-methoxyquinoline (0.55 g, 2.60 mmol, 36% yield) as white solid.
Workup
- customThe POCl3 was removed under reduced pressure