General procedure for the synthesis of bis[2-((oxo)diphenylphosphino)phenyl] ether from bis(2-diphenylphosphino)phenyl ether: compound 8 (5.0 g, 9.3 mmol) was dissolved in 100 mL of dichloromethane, and 30% hydrogen peroxide solution (4.0 mL, 186 mmol) was added slowly and dropwise under the cooling of an ice bath. The reaction mixture was stirred under ice bath conditions for 4 hours. After completion of the reaction, the reaction was quenched with distilled water and extracted three times with dichloromethane. The organic layers were combined, dried with anhydrous magnesium sulfate and the solvent was removed by distillation under reduced pressure. The resulting solid was purified by hexane reprecipitation to afford compound 9 (white powder, 5.0 g, 94% yield). IR (ATR) analysis showed characteristic peaks at 1183 cm^-1 (strong absorption, P=O) and 1070-1226 cm^-1 (strong absorption, C-O-C).1H NMR (300 MHz, CDCl3, 25°C) δ 7.06- 7.71 (m, 26H, Ar), 6.02-6.07 (m, 2H, Ar) ppm.31P NMR (200 MHz, CDCl3, 25°C) δ 26.41 (2P) ppm.FAB-MS (m/z) = 571 [M + H]+.
![Bis[2-(diphenylphosphino)phenyl] ether oxide](/CAS/20150408/GIF/808142-23-6.gif)