Diethyl phosphorochloridate

Difluoroalkylphosphonates, prepared from difluoroaliylic allcoxides and diethyl phosphorochloridate, are remarkably stable [78] (equation 65). 

Water hydrolyzes diethyl phosphorochloridate [chloro-diethoxyphosphorus(V) oxide] readily but does not affect the diene. Alternatively, the reaction mixture can be processed by fractionation. Evaporation of the petroleum ether and fractionation of the residue through a 25-cm. x 2.2-cm. column of glass helices yields 170 g. (98.5%) of diethyl phosphorochloridate, b.p. 34-36°/0.2 mm., d 1.4210-1.4250 (the refractive index indicates that it contains 5-10% of the title compound), and 240-255 g. (90-96%) of l,2,3,4,5-pentachloro-5-ethylcyclo-pentadiene, b.p. 51-53°/0.2 mm., 1.5398. 

The reaction mixture can also be processed by chromatography. The crude reaction mixture is poured on a 90-cm. x 4.5-cm. column of alumina (e.g, Fisher adsorption grade ) and eluted with about 2 1. of technical-grade pentane. This yields a pale-yellow solution that is free of diethyl phosphorochloridate. Evaporation of the pentane gives 240-255 g. (90-96%) of l,2,3,4,5-pentachloro-5-ethylcyclopentadiene. 

The ester/alkyne rearrangement system can be extended by conjugation to involve a more distant site. The reaction of diethyl phosphorochloridate with 3-methylhex-4-yne-2-ene-l-ol leads to the vinylogous propargylic ester rearrangement as shown in Equation 4.39.176... 

Diethyl malonate, condensation with acetone, 50, 39 Diethyl 5-methylcoprost-3-en-yl phosphate, 52, 109 Diethyl phosphorochloridate,... 

The disadvantage of this method, especially for large-scale work, lies in the utilization of large quantities of pyridine. Furthermore, with ethyl alcohol some ethyl phosphorodichloridate (II) is usually produced even under conditions favourable to the production of diethyl phosphorochloridate. 

The diethyl phosphorochloridate was characterized by the Ciystalline diethyl phenylphosphoramidate (VI) formed by the action of aniline. 

The 2-chloroethyl group, which is often an effective toxo-phore, was then attached to phosphorus through oxygen. No reaction appeared to take place between ethylene chlorohydrin and diethyl phosphorochloridate in the absence of a tertiary base. In the presence of pyridine, however, which removed the hydrogen chloride formed, a smooth reaction took place at 0° with the formation of diethyl 2-chloroethyl phosphate,... 

Tetraethyl pyrophosphate (T.E.P.P.) was prepared by Toy1 in 73 per cent yield by the controlled hydrolysis of diethyl phosphorochloridate in the presence of a tertiary base ... 

Kosolapoff2 has prepared T.E.P.P. by the action of chlorine on a mixture of sodium diethyl phosphate and diethyl phosphorochloridate followed by the addition of an excess of alcohol. 

This compound was designated E-600 by Schrader,3 who prepared it by the reaction of sodium p-nitrophenate on diethyl phosphorochloridate in xylene ... 

A thorough examination of the whole problem was carried out by Gardner and Heath. Using diethyl phosphorochloridate containing 32P, they prepared compound (VIII) thus ... 

Toy2 prepared this ester3 (as well as related esters) by the controlled hydrolysis of 2 mol. of diethyl phosphorochloridate ... 

Commercial diethyl phosphorochloridate [b.p. 60-62° (1.5 mm.)], purchased from Eastman Organic Chemicals, was distilled prior to use in this reaction. 

Phosphate groups can also be removed by dissolving-metal reduction. Reductive removal of vinyl phosphate groups is one of the better methods for conversion of a carbonyl compound to an alkene.150 151 The required vinyl phosphate esters are obtained by phosphorylation of the enolate with diethyl phosphorochloridate or NJ, N, N -tetra-methyldiamidophosphorochloridate.152 153... 

The conj ugate addition of lithium dimethylcuprate and other organoeopper reagents to a,/ -unsaturated ketones is a reaction which has had wide application and which has been fairly well studied.6 In order that the positional specificity which has been conferred upon the enolate anions generated by such additions might be maintained, these intermediates have been intercepted with acetic anhydride,6 chlorotrimethylsilane, and diethyl phosphorochloridate.4 8... 

Diethyl 2-pentenedioate, d307 Diethyl phosphite, d314 Diethyl phosphorochloridate, d291 Diethyl phosphorochloridothionate, d292 Diethyl pimelate, d309... 

Diethyl chlorophosphate, see Diethyl phosphorochloridate, 1675 Diethyl diazomalonate, 2824 Diethyl-3-diethylaminopropylaluminium, 3408 Diethyl l,4-dihydro-2,6-dimethylpyridine-3,5-dicarboxylate, 3609 3,6-Diethyl-3,6-dimethyl-1,2,4,5-tetraoxane, 3047... 

Ammonium perchlorate, Impurities, 3998 Azidoacetic acid, 0770 f Aziridine, Acids, 0859 Benzoyl azide, 2694 Benzyl chloroformate, 2926 1,2-Bis(difluoroamino)-/V-nitroethylamine, 0799 Bromine trioxide, 0259 2-Butanone oxime, 1649 2-Butyne-l,4-diol, 1523 Butyraldehyde oxime, 1650 Carbon, Unsaturated oils, 0297 Chlorine, Carbon disulfide, 4041 f l-Chloro-2,3-epoxypropane, Contaminants, 1158 Cyanogen chloride, 0322 Diethyl phosphorochloridate, 1675 f 1,1-Difluoroethylene, 0696... 

In preparation for the eventual removal of the undesired oxygen function at C-10 of 313 via a Birch reduction, the phenol 313 was phosphorylated with diethyl phosphorochloridate in the presence of triethylamine to give 314, which underwent stereoselective reduction with sodium borohydride with concomitant N-deacylation to deliver the amino alcohol 315. N-Methylation of 315 by the Eschweiler-Clarke protocol using formaldehyde and formic acid followed by ammonolysis of the ester group and acetylation of the C-2 hydroxyl function afforded 316. Dehydration of the amide moiety in 316 with phosphorus oxychloride and subsequent reaction of the resulting amino nitrile 317 with LiAlH4 furnished 318, which underwent reduction with sodium in liquid ammonia to provide unnatural (+)-galanthamine. 

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