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

Participants

Reaction Steps

A finely ground mixture of 1-methyl-4-(propylsulfonyl)benzene (Intermediate 36; 24.80 g; 0.13 mol) and N-bromosuccinimide (26.8 g; 0.15 mol) was treated with conc. sulfuric acid (115 ml; 2.15 mol). The reaction mixture was stirred for 16 h then treated with a further portion of N-bromosuccinimide (1.33 g; 0.01 mol). The reaction solution was stirred 1 h then carefully poured into 800 mL of crushed ice. The aqueous solution was extracted with 400 mL of AcOEt. The layers were separated and the organic phase was washed first with ca. 300 mL of brine, then twice with a 1N solution of NaOH in water and twice with brine. The organic phase was dried on MgSO4, filtered and concentrated under reduced pressure to give the title compound (29.3 g, 85%) as a brown oil which solidified upon standing.

Provenance & Evidence