Potassium Phosphate, Tribasic → Ethyl 1-(2,4-difluorophenyl)-6,7-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate

Participants

Reaction Steps

8.0 g of ethyl 2-(2-chloro-4,5-difluorobenzoyl)-3-(2,4-difluorophenylamino)acrylate was dissolved in 80 ml of acetonitrile under heating to 75˜80° C. 11.84 g (2.8 eq.) of K3PO4 was added in portions to the reaction mixture, which was then stirred at the same temperature for 2 hours. The reaction mixture was filtered under a reduced pressure and washed with 40 ml of dichloromethane. The filtrate was concentrated under a reduced pressure. The resulting residue was dissolved in 88 ml of dichloromethane and then washed with water. The organic layer was concentrated under a reduced pressure to give 6.69 g of ethyl 1-(2,4-difluorophenyl)-6,7-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate (Yield: 92%).

Provenance & Evidence