[Br:1][C:2]1[CH:3]=[C:4]([CH:8]([OH:12])[C:9](O)=O)[CH:5]=[CH:6][CH:7]=1.[F:13][C:14]1[CH:19]=[CH:18][C:17]([NH2:20])=[C:16]([NH2:21])[CH:15]=1.[OH-].[Na+]>>[Br:1][C:2]1[CH:3]=[C:4]([CH:8]([C:9]2[NH:20][C:17]3[CH:18]=[CH:19][C:14]([F:13])=[CH:15][C:16]=3[N:21]=2)[OH:12])[CH:5]=[CH:6][CH:7]=1A mixture of (3-bromophenyl)hydroxyacetic acid (3.7 g) and 4-fluoro-ortho-phenylenediamine (2 g) in 5N aqueous hydrochloric solution (3.2 mL) is heated under reflux for 15 h and cooled back to room temperature. The mixture is basified with concentrated sodium hydroxide and extracted with ethyl acetate. The organic phase is then dried over magnesium sulfate and concentrated under reduced pressure. The residue is purified by chromatography over silica gel (gradient dichloromethane/methanol/ammonia from 98/2/0.5 to 90/10/0.5) to afford the pure 3-bromophenyl(5-fluoro-1H-benzimidazol-2-yl)methanol.
Wird geladen…