Bis(4-bromophenyl)(phenyl)phosphine oxide

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 10.05 g (24 mmol) of bis(4-bromophenyl)phenylphosphine were dissolved in 200 ml of ethyl acetate in a 500 ml four-necked flask with internal thermometer, mechanical stirrer, reflux condenser and dropping funnel and cooled to an internal temperature of 5° C. A solution of 2.25 ml (26.4 mmol) of H2O2 (35%) in 17.5 ml of water was added dropwise over the course of 30 min., and the mixture was stirred at room temperature for a further 12 h. 25 ml of saturated sodium sulfite solution were subsequently added, the organic phase was separated off, washed twice with saturated sodium sulfite solution and dried over sodium sulfate. The solvent was removed under reduced pressure. The purification was carried out firstly by column chromatography on silica using a solvent mixture of initially hexane:ethyl acetate 2:1 to hexane:ethyl acetate 1:1. Further purification was carried out by recrystallisation from heptane/toluene, giving 6.5 g of product in a purity of 99.7% (according to HPLC). 1H-NMR (500 MHz, CDCl3): [ppm] 7.46-7.66 (m). 31P-NMR (CDCl3): [ppm] 28.40. reflux condenser the organic phase was separated off washed twice with saturated sodium sulfite solution dried over sodium sulfate The solvent was removed under reduced pressure The purification a solvent mixture of initially hexane:ethyl acetate 2:1 to hexane:ethyl acetate 1:1 Further purification was carried out by recrystallisation from heptane/toluene

Conditions: temp:5.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 10.05 g (24 mmol) of bis(4-bromophenyl)phenylphosphine were dissolved in 200 ml of ethyl acetate in a 500 ml four-necked flask with internal thermometer, mechanical stirrer, reflux condenser and dropping funnel and cooled to an internal temperature of 5° C. A solution of 2.25 ml (26.4 mmol) of H2O2 (35%) in 17.5 ml of water was added dropwise over the course of 30 min., and the mixture was stirred at room temperature for a further 12 h. 25 ml of saturated sodium sulfite solution were subsequently added, the organic phase was separated off, washed twice with saturated sodium sulfite solution and dried over sodium sulfate. The solvent was removed under reduced pressure. The purification was carried out firstly by column chromatography on silica using a solvent mixture of initially hexane:ethyl acetate 2:1 to hexane:ethyl acetate 1:1. Further purification was carried out by recrystallisation from heptane/toluene, giving 6.5 g of product in a purity of 99.7% (according to HPLC). 1H-NMR (500 MHz, CDCl3): [ppm] 7.46-7.66 (m). 31P-NMR (CDCl3): [ppm] 28.40. reflux condenser the organic phase was separated off washed twice with saturated sodium sulfite solution dried over sodium sulfate The solvent was removed under reduced pressure The purification a solvent mixture of initially hexane:ethyl acetate 2:1 to hexane:ethyl acetate 1:1 Further purification was carried out by recrystallisation from heptane/toluene