反应详情

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.

1. additionThe reaction mixture was carefully poured
2. customon crushed ice
3. extractionextracted with AcOEt
4. washthe organic phase was washed with a 0.1 N solution of NaOH in water twice
5. customThe organic phase was dried on MgSO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customto give a residue, which
9. customwas purified by flash column chromatography (silica)
10. washeluting with cyclohexane containing
11. temperatureincreasing amounts of EtOAc