[Cl:1][C:2]1[N:12]=[C:11](Cl)[C:10]([F:14])=[CH:9][C:3]=1[C:4]([O:6][CH2:7][CH3:8])=[O:5].[F:15][C:16]1[CH:17]=[C:18]([OH:23])[CH:19]=[CH:20][C:21]=1[F:22].C(=O)([O-])[O-].[K+].[K+]>C(#N)C>[Cl:1][C:2]1[N:12]=[C:11]([O:23][C:18]2[CH:19]=[CH:20][C:21]([F:22])=[C:16]([F:15])[CH:17]=2)[C:10]([F:14])=[CH:9][C:3]=1[C:4]([O:6][CH2:7][CH3:8])=[O:5]To a solution of ethyl 2,6-dichloro-5-fluoronicotinate (20 g, 84 mmol) and 3,4-difluorophenol (10.93 g, 84 mmol) in acetonitrile (200 mL) was added potassium carbonate (20.90 g, 151 mmol). The reaction mixture was stirred at 80° C. for 2 hr. and then concentrated under reduced pressure. The crude product was purified by silica gel chromatography eluting with Hex/EtOAc (10:1) to give ethyl 2-chloro-6-(3,4-difluorophenoxy)-5-fluoronicotinate (23.5 g, 80%).
Wird geladen…