Under argon protection, 4-bromobiphenyl (47.0 g, 201.6 mmol), iodine (23.0 g, 90.6 mmol) and disodium hydriodate (9.4 g, 41.2 mmol) were added sequentially to the reaction flask. Subsequently, water (42 mL), acetic acid (360 mL) and sulfuric acid (11 mL) were added to the reaction system. The reaction mixture was heated to 65 °C and stirred at this temperature for 30 min. Then, the temperature was raised to 90 °C and the reaction continued to be stirred for 6 hours. Upon completion of the reaction, the reaction mixture was slowly poured into ice water to precipitate a solid. The solid product was collected by filtration and washed sequentially with water and methanol to give a final white solid 4-bromo-4'-iodobiphenyl (67.0 g, 93% yield).
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[2] Patent: US2011/95269, 2011, A1
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