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5525-40-6

The general procedure for the synthesis of (4-bromophenyl)diphenylphosphine oxides using diphenyl(4-bromophenyl)phosphine as starting material was as follows: diphenyl(4-bromophenyl)phosphine (20 g, 58 mmol) was dissolved in trichloromethane (200 ml), followed by the slow addition of hydrogen peroxide solution (20 ml). The reaction mixture was stirred at room temperature for 12 hours. After completion of the reaction, the organic phase was separated and dried over anhydrous magnesium sulfate. The desiccant was removed by filtration and the filtrate was concentrated under reduced pressure. The resulting crude product was recrystallized from hexane to give white crystalline (4-bromophenyl)diphenylphosphine oxide (18 g, 85% yield).