To a solution of 2-bromo-4-chlorophenol (4.98 g, 24.0 mmol) in N,N-dimethylformamide (DMF, 25 mL) was sequentially added sodium difluorochloroacetate (8.42 g, 55.2 mmol), cesium carbonate (10.97 g, 33.67 mmol) and water (2.5 mL). The reaction mixture was stirred at 100 °C for 16 hours. After completion of the reaction, the mixture was partitioned between ethyl acetate and water, and the organic phase was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. The crude product was purified by silica gel fast column chromatography eluting with 0-20% ethyl acetate/heptane gradient to afford 2-bromo-4-chloro-1-(difluoromethoxy)benzene as a colorless, transparent oil (2.98 g, 48% yield).No molecular ion peak was detected by LC-MS (ESI); 1H NMR (400 MHz, DMSO-d6) δ: 7.90 (d, 1H) , 7.54 (dd, 1H), 7.38 (d, 1H), 7.28 (t, 1H).
