Ethylphosphonic dichloride

Ethylphosphonyl dichloride 1066-50-8 Organic synthesis Specific uses not identified see ethylphosphonous dichloride Ethyl sarin (GE) 2.10... 

The volatility of phosphorus trichloride, ethylphosphonous dichloride and sulphuryl chloride, permit of their quantitative transfer in a high-vacuum system. The conversion of the phos-phonous into the phosphonic dichloride can also be carried out in an enclosed system.5... 

The probable impurities in radioactive phosphorus trichloride are hydrogen chloride and phosphorous acid the trichloride is, therefore, purified by fractional evaporation and fractional condensation in the high-vacuum system. Pure ethylphosphonous dichloride is prepared according to the equation ... 

The reaction vessel is attached to the high-vacuum system, and the phosphorus trichloride transferred to it without loss and without risk. Further to reduce the hazards, a powerful magnetic stirrer is employed. The ethylphosphonous dichloride is then oxidized in benzene solution in a vessel connected directly to the vacuum system. 

The final method (equation 31) shows the preparation of ethylphosphonous dichloride" from tetraethyl lead and an excess of phosphorus trichloride. The product can be isolated in high yield (89%) and is more easily separated from excess phosphorus trichloride than the methyl analogue because of the greater difference in b.p. (20 °C). The method is suited to both laboratory and plant production. 

Methyl phosphorodichloridite Dimethyl phosphorochloridite Trimethyl phosphite Trimethyl phosphorotrithioite Hexamethylphosphorous triamide Methyl tetramethylphosphorodiamidite Dimethyl dimethylphosphoramidite Methyl diethylphosphoramidochloridite 0-Methyl S.S-diethyl phosphorodithioite Ethylphosphonous acid Ethylphosphonous dichloride Methyl ethylphosphonochloridite Dimethyl ethylphosphonite 0-Methyl S-phenyl ethylphosphonothioite Dibutyl phosphonite ... 

Ethylphosphonous dichloride, EtPCl2, can be obtained in 95% yield by slowly adding lead tetraethyl to well-stirred phosphorus trichloride in a nitrogen atmosphere, followed by refluxing at 110°C for 30 h. This alkylation can be carried out stepwise, using different alkyl in each stage, if mixed phosphines are required. 

Ethyl chloride, AIGI3, and PGI3 shaken 2 hrs. at room temp, in a pressure bottle, then heated 1 hr. at 100°, powdered under Ng, dissolved in ethyl phthalate with cooling, degassed at 55°/2 mm, cooled to room temp., powdered antimony added to the well-stirred mixture with ice-cooling when the temp, has reached 65°, which is then followed hy a further rise to 75°, and the product isolated after 30 min. ethylphosphonous dichloride (st tg. m. f. 650). Y 83%. F. e. s. B. J. Perry, J. B. Reesor, and J. L. Perron, Gan. JJ Ghem. 41, 2299 (1963) reductive P-dechlorination with Mg, phospholincs, s. L. D. Quin et al., Tetrah. Let. 1964, 3689. 

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