N-bromobutanimide → 4-Bromo-5-(bromomethyl)-2-chloropyridine

A flask was charged with 4-bromo-2-chloro-5-methylpyridine (513 mg, 2.48 mmol), (PhCO2)2 (32 mg, 0.13 mmol), and NBS (452 mg, 2.54 mmol) then diluted with CCl4 (9 mL). The reaction mixture was heated to reflux for 2 hours and then allowed to cool to room temperature and diluted with CH2Cl2 and H2O. The layers were separated and the aqueous layer was extracted with CH2Cl2. The combined organic extracts were dried over Na2SO4, filtered, and concentrated in vacuo. The crude residue was purified by silica gel column chromatography (0-20% EtOAc/Hex gradient) to afford the desired product. LCMS-ESI+: calc'd for C6H5Br2ClN 283.9 (M+H+); Found: 283.9 (M+H+).