[Br:1][C:2]1[CH:10]=[C:9]2[C:5]([CH:6]([C:12]3[CH:17]=[CH:16][C:15]([C:18]([F:21])([F:20])[F:19])=[CH:14][C:13]=3[O:22][CH3:23])[O:7][C:8]2=[O:11])=[CH:4][CH:3]=1.[OH-].[K+].[Mn]([O-])(=O)(=O)=[O:27].[K+]>N1C=CC=CC=1>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([C:6](=[O:7])[C:12]2[CH:17]=[CH:16][C:15]([C:18]([F:19])([F:21])[F:20])=[CH:14][C:13]=2[O:22][CH3:23])=[C:9]([CH:10]=1)[C:8]([OH:27])=[O:11]To a stirred mixture of 6-bromo-3-(2-methoxy-4-(trifluoromethyl)phenyl)isobenzofuran-1(3H)-one (2.06 g, 5.32 mmol) in KOH (21.3 mL, 5.32 mmol, 25% aqueous solution) and pyridine (10.6 mL) in a pressure tube was added powder potassium permanganate (1.26 g, 7.98 mmol). The reaction was heated at 100° C. After 4 h, the reaction was cooled to RT and the mixture was filtered, and the residue was washed with water. The filtrate was acidified with concentrated HCl until a pH of about 2. The white solid that precipitated out of the solution was filtered off with the aid of water and dried to afford 5-bromo-2-(2-methoxy-4-(trifluoromethyl)benzoyl)benzoic acid (2.16 g, 100% yield). This material was carried on to the next step. m/z (ESI) 405.0 (M+H)+.
Wird geladen…
