Phosphorus tribromide → 2-Bromo-5-bromomethylphenol

Participants

Reaction Steps

To a suspension of 2-bromo-5-hydroxymethylphenol 71 (5.17 g, 25.5 mmol) in chloroform (100 mL) at 0° C. was added a solution of PBr3 (1.21 g 12.7 mmol) in chloroform (60 mL) over 30 min. The resultant solution was stirred at 0° C. for 1 h, and then was warmed to room temperature and stirred for an additional 1.75 h. After this time, the reaction mixture was poured into ice water and extracted with dichloromethane (2×). The organic layers were dried over Na2SO4, filtered, and the filtrate was purified by silica gel chromatography (eluent: dichloromethane:EtOAc, 95:5) to give 72. 1H NMR (400 MHz CDCl3) δ: 4.40 (s, 2H), 5.52 (s, 1H), 6.85 (dd, J=8.2 Hz, 2.1 Hz, 1H), 7.06 (d, J=2.1 Hz, 1H), 7.43 (d, J=8.2 Hz, 1H). MS (EI) m/z (M−H−) 263.

Provenance & Evidence