Synthesis of Tris-p- 3-phenylpropyl phenylphosphine

Tris-p-(3-phenylpropyl)phenylphosphine (5 g, 8.1 mmol) is placed into a 1000-mL flask, cooled to — 78°C, and 20 mL 96% H2S04 is then added with stirring. With continued stirring, the mixture is allowed to come slowly to room temperature. After about 6 h, the brown reaction mixture is neutralized by slow addition of 20% NaOH. The pH is adjusted to 9 and the final volume is about 120 mL. Methanol (720 mL) is added and the mixture is heated to reflux for 30 min, filtered through a medium-porosity frit, and the precipitate is extracted with 200 mL of hot methanol. After two extractions in this manner, the two filtrates are combined and the volume is reduced to about 45 mL. Acetone (270 mL) is added to precipitate the white trisulfonated tris-p-(3-phenylpropyl)phenylphosphine which is collected and dried. Yield 6.9 g, 92%. 

4-BIS DI[/7-(3-[/7-SODIUMSULFONATO]PHENYL-PROPYL)PHENYLPHOSPHINO PENTANE (BDAPPTS)6 

All manipulations and syntheses are performed under prepurified argon or nitrogen using standard Schlenk techniques. All solvents are degassed by distillation under nitrogen prior to use. The 2,4-pentanediol enantiomers and p-toluenesulfonyl chloride were obtained from Aldrich and used as received. The ditosylate of pentanediol was prepared from optically pure 2,4-pentanediol following a literature procedure as follows.8 

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