Sulfuric Acid → 2-Bromo-1-fluoro-4-(propylsulfonyl)benzene

Participants

Reaction Steps

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.

Provenance & Evidence