Triphenylphosphine → 2-(3-Bromopropyl)thiophene

Compound 46-2 (1.29 g) was dissolved in methylene chloride (30 ml), triphenylphosphine (2.62 g) and N-bromosuccinimide (1.76 g) were added under ice-cooling, and the mixture was stirred under ice-cooling for 2 hr. The reaction mixture was washed with water and saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure. Diethyl ether (50 ml) was added, and the precipitated triphenylphosphine oxide was filtered off. The concentrate of the filtrate was purified by silica gel column chromatography (hexane alone) to give the object product (760 mg) as a pale-yellow oil.