p-Toluenesulfonic acid → 2-Bromo-6-methoxybenzo[b]thiophene

Participants

Reaction Conditions

Reaction Steps

N-bromosuccinimide (14.70 g, 82.59 mmol) and p-toluenesulfonic acid (2.70 g, 15.68 mmol) were added to a solution of benzothiophene (3) (15.10 g, 92.07 mmol) in 1,2-dichloroethane (300 ml). The mixture was maintained at 70° C. for 35 min, cooled in an ice bath, and the succinimide was removed by filtration. The solution was extracted with saturated sodium bicarbonate solution, dried over Na2SO4, filtered, and concentrated under vacuum to give 22.00 g as an oil. Crystallisation from pentane afforded a white solid (16.50 g, 74%), mp 62° C.

Provenance & Evidence