[F:1][C:2]([F:16])([F:15])[C:3]([C:5]1[CH:10]=[CH:9][CH:8]=[C:7]([C:11]([F:14])([F:13])[F:12])[CH:6]=1)=[O:4].[Br:17]N1C(C)(C)C(=O)N(Br)C1=O>C(O)(=O)C.S(=O)(=O)(O)O>[Br:17][C:9]1[CH:10]=[C:5]([C:3](=[O:4])[C:2]([F:15])([F:16])[F:1])[CH:6]=[C:7]([C:11]([F:12])([F:13])[F:14])[CH:8]=1To a stirred solution of 2,2,2-trifluoro-1-[3-(trifluoromethyl)phenyl]ethanone (5.00 g) in glacial acetic acid (1.0 mL) and concentrated sulfuric acid (6.0 mL) at 0° C. was added 1,3-dibromo-5,5-dimethylhydantoin (3.54 g). After stirring at 35° C. for 3.5 hours, the reaction mixture was poured into ice-water (60 mL) and extracted with chloroform (30 mL×2). The organic extracts were combined, washed with saturated aqueous sodium hydrogencarbonate solution (50 mL×1) and brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The resulting residue was dissolved in hexane (20 mL) and filtered, and the filtrate was concentrated under reduced pressure to provide the title compound as a yellow oil (6.50 g).
Loading…
