8- methylphosphonate, diethyl

Two methods can be used to prepare phosphonodithioacetate 28 (Scheme 7). One method consists of the addition of methyl chlorodithioformates to the cuprate of a diethyl methylphosphonate [19], the other is the addition of HCl gas and EtSH to a diethyl (cyanomethyl)phosphonate followed by a sulfhydrolysis in pyridine [20]. 

Diethanol Sulfide Diethanolamine Diethanolethylamine Diethanolmethylamine Diethoxyethylphosphine Oxide Diethoxymethylphosphine Oxide Diethoxyphosphine Oxide Diethyene Disulfide Diethyl Acid Phosphate Diethyl Ethanephosphonate Diethyl Ethylphosphonate Diethyl Hydrogen Phosphate Diethyl Hydrogen Phosphite Diethyl Hydrogen Phosphonate Diethyl Isopropylphosphonate Diethyl Methanephosphonate Diethyl Methylphosphonate Diethyl Phosphate Diethyl Phosphite Diethyl Phosphonate Diethyl Phosphoric Acid Diethyl(2-hydroxyethyl)amine Diethyl(/S-hydroxyethyl)amine Diethylaminoethanol Diethylethanolamine Diethylfosfit... 

Compound (VI) is usually described as benzene sulphonic acid, but it k probably more correctly described as phenylsulphonic acid. Accordingly (X) is described as diethyl methylphosphonate. 

The reaction of the carbanion derived from diethyl methylphosphonate with perhalogenated aromatics may result in substitution of halide to yield perhaloaryl(hetaryl)methylphosphonates, which can be converted into tris- or bis-(perhaloaryl)methanes. Displacement of fluoride ion has been reported in the reaction of dimethoxycarbene with l-fluoro-2,4-dinitrobenzene and with hexafluorobenzene. The hydrodehalogenation of halogenated aryl ketones may be facilitated using hydrogen over a Pt/C catalyst. " ... 

We synthesized EPMP, by the method of Fukuto and Metcalf ( ) by reacting diethyl methylphosphonate with phosphorus penta-chlorlde, followed by reaction with sodium -nltrophenolate. EPMP was purified by distillation at reduced pressure. Analysis for C9H12NO5P. Calculated % C, 44.1 % H, 4.93 % N, 5.71. Found % C, 43.9 % H, 4.77 % N, 4.59. [Caution EPMP Is a VERY TOXIC NERVE POISON the subcutaneous lethal dose (LD50) In mice is 350 pg/kg (R. Howd, R. Kenley, unpublished), and the material should be handled with extreme care at all times.]... 

Diethyl methylphosphonate, 31, 34 Diethyl o-nitrobenzoylmalonate, 30, 71 Diethyl oxalate, 34, 13 Diethyl co-phthalimidobutylmalonate, 32, 15... 

Diethyl methylphosphonate may be prepared similarly by refluxing one molar equivalent of triethyl phosphite with one mole of methyl iodide, but it is very difficult to separate the product from the small amount of diethyl ethylphosphonate that is formed simultaneously by the interaction of the phosphite with the ethyl iodide liberated in the reaction. The pure substance boils at 51°/1 mm., no 1.4117, dl5 1.050. 

Under an atmosphere, diethyl methylphosphonate was dissolved in freshly distilled THF (LiAlH4) so as to give a ca. 0.5 M solution. The solution was cooled to — 78 C on a MeOH/dry ice bath, and BuLi (1.2 equiv) was added to this solution with stirring. After 15 min, a solution (ca. 1 M) of 1,1-dibromocy-clopropane was slowly added at — 78 C. The ratio of dibromide to reagent was usually taken to be 1 1.5. The resulting mixture was allowed to stand overnight at rt, treated with ice-cold HjO, and extracted three times with EtjO. The combined Et20 extracts were concentrated in vacuo, and the products were isolated in the usual way. 

The reduction of diethyl chlorofluoromethylphosphonate with H2/Raney Ni in the presence of Et3N affords diethyl fluoromethylphosphonate in 43%, contaminated with the C-F bond cleavage product, diethyl methylphosphonate (32%). ... 

Diethyl methylphosphonate reacts with phenylsulfonyl chloride (2 eq) in the presence of n-BuLi (3 eq) to produce diethyl 1-lithio-1,1-dichloromethylphosphonate, which can be quenched in quantitative yield or reacted directly with a large variety of carbonyl compounds (Homer-Wadsworth-Eimnons reaction), thus providing a useful one-pot process for the synthesis of dichloroalkenes. ... 

Artamkina, G.A., Tarasenko, E.A., Lukashev, N.V., and Beletskaya, LP, Synthesis of perhaloaromatic diethyl methylphosphonates containing a-electron-withdrawing group. Tetrahedron Lett., 39, 901,... 

Diethyl l-(hydroxycarbonyl)methylphosphonate is Ihennally stable up to 150°C. - Decomposition associated with distillation begins at 160°C to give diethyl methylphosphonate (17%), diethyl 1-(ethoxycarbonyl)methylphosphonatc (34%), and l-(ethoxycarbonyl)methylphosphonic acid (35%). ° ... 

Diethyl methylphosphonate 0,0 -Diethyl methylphosphonate C5H13O3P 683-08-9 Present in tonne containers, degradation product and impurity... 

The nerve agents are generally considered to be acute toxicants and their delayed effects have been relatively little investigated. Li et al. (1998) reported an increase in sister chromosome exchange (SCE) in the lymphocytes of victims of the Tokyo sarin disaster. Because of the probability that the victims were exposed to by-products of sarin synthesis, diisopropyl methylphospho-nate, diethyl methylphosphonate and isopropyl ethyl methylphosphonate, these were also studied. The frequency of SCE was determined in human lymphocytes exposed to these by-products all three compounds increased the frequency of SCE compared with controls. Sarin and soman... 

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