A mixture of 3-bromo-5-(trifluoromethyl)pyridin-2-ol (37.75g, 0.16 mol) and phosphorus(lll) oxychloride (POCI3; 75 mL) is stirred at 1000C for 5 hours. After cooling to room temperature, the mixture is poured into ice-water and extracted with CH2CI2 twice. The combined organic layer is washed with NaHCO3 aq., brine, dried over MgSO4, filtered, and concentrated in vacuo. The crude mixture is purified by flash column chromatography to give 3-bromo-2-chloro-5-trifluoromethylpyridine (31.90 g, 79 % yield) as a white solid.
