Pyridine → Diisopropylphosphoramidous dichloride

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

300 ml abs. ether, 81 ml anhydrous pyridine and 87.5 ml PCl3 (1 Mol) are pre-cooled with stirring to -70° C. in a 2 l three-neck, round-bottomed flask with a 500 ml dropping funnel, KPG stirrer, thermometer and acetone/dry ice bath. 142 ml diisopropylamine (1 Mol) in 250 ml abs. ether are added dropwise to it within 2 hours and the temperature is maintained at ca -60 to -65° C. After completing the addition, the thickened pulpy reaction mixture is allowed to reach room temperature and is diluted with about 600 ml abs. ether to make it more easily stirrable. After a further 3 hours stirring at room temperature the precipitate which forms is aspirated over a glass filter and washed several times with ether. After drawing off the ether at normal pressure, it is freed of unreacted PCl3, diisopropylamine and pyridine in a water-jet vacuum and then the remaining oil is fractionally distilled under an oil-pump vacuum (Kp 46° C./0.35 Torr). 73.4 g of the phosphane is obtained which corresponds to 36% of the theoretical yield.

Herkunft & Nachweise