N-Diisobutyl-2- octylphenylphosphinyl acetamide CMPO

Crystallization. The crude CMPO (138 g) is dissolved in 500 mL of heptane and is cooled to — 15°C in a freezer. Several seed crystals are added after a few hours. After several days the crystals are collected by vacuum filtration on a Buchner funnel and washed with 200 mL of cold heptane. Residual solvent is removed at reduced pressure in a desiccator overnight to provide a 119 g of white, somewhat deliquescent, solid (mp 44-45°C). This is the preferred method of purifying the product. 

Distillation. The crude CMPO (169 g) is distilled through a short, wide, connecting tube into a dry-ice cooled receiver at reduced pressure (bath temperature of 220°C/0.001 torr). A significant degree of decomposition is observed during the distillation. The impurities from the distillate are removed by washing a heptane solution with 5% Na2C03. 

The resultant solid mercury salt is contacted with a mixture of 23 g potassium cyanide (n Caution. Cyanide compounds are extremely poisonous.) and 48 g potassium carbonate in 350 mL of water and 200 mL of heptane. After stirring for several hours, the phases were separated. The heptane phase is stirred vigorously with 12.5 g KCN and 24 g K2C03 in 175 mL water. After separating the phases, the organic phase is washed successively with 250 mL portions of 0.5 M K2C03, HzO, 0.5 M HN03, 0.5 M NaOH, and H20. The solvent is concentrated at reduced pressure to provide 52 g of the title compound. 

NMR The decoupled phosphorus-31 signal is recorded in CDC13 at 37.67 ppm downfield from external 85% phosphoric acid.7 The proton spec- 

SUBMITTED BY SUSHIL K. PANDEY, ALEXANDER STEINER, and HERBERT W. ROESKY  

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