Sulfuric Acid → 2-Bromo-1-fluoro-4-(propylsulfonyl)benzene
Reaktionsgleichung
[F:1][C:2]1[CH:7]=[CH:6][C:5]([S:8]([CH2:11][CH2:12][CH3:13])(=[O:10])=[O:9])=[CH:4][CH:3]=1.S(=O)(=O)(O)O.[Br:19]N1C(=O)CCC1=O>>[Br:19][C:7]1[CH:6]=[C:5]([S:8]([CH2:11][CH2:12][CH3:13])(=[O:10])=[O:9])[CH:4]=[CH:3][C:2]=1[F:1]Komponenten
4
Versuchsvorschrift
A suspension of 1-fluoro-4-(propylsulfonyl)benzene (Intermediate 105; 1.00 g; 4.94 mmol) in conc. sulfuric acid (3.97 ml; 74.2 mmol) was treated with N-bromosuccinimide (968 mg; 5.44 mmol) and stirred at RT for 6 hours. The reaction mixture was carefully poured on crushed ice, extracted with AcOEt and the organic phase was washed with a 0.1 N solution of NaOH in water twice, then with brine twice. The organic phase was dried on MgSO4, filtered and concentrated under reduced pressure to give a residue, which was purified by flash column chromatography (silica), eluting with cyclohexane containing increasing amounts of EtOAc to give the title compound.