To a solution of (6-bromo-3-methyl-benzofuran-2-yl)-(2,4-dichloro-phenyl)-methanone (3.0 g, 7.81 mmol) in carbon tetrachloride (30 mL) was added N-bromosuccinimide (1.46 g, 8.2 mmol) and 2,2′-azobisisobutyronitrile (128 mg, 0.78 mmol). The reaction mixture was refluxed for 6 h, then filtered. The filtrate was concentrated and the crude product was triturated with 10% EtOAc/hexane to afford the desired product as a pale yellow solid (2.85 g, 78.9%). This material was used in the subsequent step without further purification.
