[Cl:1][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[N:12]([C:13]3[CH:18]=[CH:17][C:16]([Cl:19])=[CH:15][C:14]=3[Cl:20])[N:11]=[C:10]([C:21]([O:23][CH2:24][CH3:25])=[O:22])[CH:9]=2)=[CH:4][CH:3]=1.[Cl:26]Cl>C(O)(=O)C>[Cl:26][C:9]1[C:10]([C:21]([O:23][CH2:24][CH3:25])=[O:22])=[N:11][N:12]([C:13]2[CH:18]=[CH:17][C:16]([Cl:19])=[CH:15][C:14]=2[Cl:20])[C:8]=1[C:5]1[CH:4]=[CH:3][C:2]([Cl:1])=[CH:7][CH:6]=1To a solution of ethyl 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-1H-pyrazole-3-carboxylate (3.0 g, 7.6 mmol) in acetic acid (30 ml) at room temperature was bubbled chlorine gas for 10 minutes. The reaction mixture was stirred at room temperature for 2 hours and the resulting solution was quenched with water (100 ml). The organic solution was extracted with diethyl ether (100 ml×2). With saturated sodium bicarbonate solution, remained acetic acid was removed and organic phase was evaporated with reduced pressure. The crude residue was purified with silica gel column (hexane/ethyl acetate=5/1) to produce title compound (3.1 g, 95% yield) as white solid.
Wird geladen…