Dichlorophosphites

But neutralized phosphorous acid monoesters of alcohols were found to have detergent and plasticizing properties [60,74]. They can be obtained by reaction of phosphorous trichloride and fatty alcohols in equimolar ratios followed by saponification of the unreacted chlorine atoms of the dichlorophosphites with a base see Eqs. (26) and (27). 

A convenient synthesis of uridine 2, 3 -cyclic phosphite 15 (as a 3 4 mixture of diasteroisomers because of the chirality at phosphorus) was based on the reaction of the suitably protected uridine derivative 14 with ethyl dichlorophosphite carried out in the presence of triethylamine and anhydrous ethanol (Scheme 6) [21]. After adding ethanol into the reaction medium, an efficient chromatographic separation of the crude reaction product was achieved on silica gel with diethyl ether giving analytically pure phosphite 15 in 75% yield. It is interesting to note that without adding ethanol, 15 is very unstable. 

Ethoxy-l,3,2-oxazaphospholidine 59 was prepared as a single diastereomer from (-)ephedrine (42) and ethyl dichlorophosphite 57. Its Arbusov reaction with allyl bromide gave the corresponding allyl phosphonates 61a,b as a diastereomeric mixture which could be separated by flash column chromatography and crystallization (Scheme 21) [48], On applying a similar protocol, starting from... 

A rich family of 2-alkoxycarbonyl-l,3,2-oxazaphospholidine-2-oxides 179-181 was prepared from the reaction of camphor derived aminoalcohols 177 and 178 with either methoxycarbonyl phosphonic dichloride or ethyl dichlorophosphite followed by the reaction with methyl bromoacetate. The reaction with aminoalcohol 177a afforded the phosphorus epimers 179 and 180, in ratios from 1/1 to 12/1 depending on the iV-substituent which could be separated easily by column chromatography. The reaction with aminoalcohols 178a-c, however, gave a single epimer 181a-c in each case (Scheme 50) [81]. 

Almost diastereomerically pure (2i ,55)-l,3-diaza-2-methoxy-3-alkyl-2-phosphabicyclo[3.3.0]octanes (201a-d) were formed in the reaction of (S)-2-anilinomethyl)-pyrrolidines (197b-e) with methyl dichlorophosphite in the presence of NEt3 (Scheme 55) [86], With these ligands, high stereoselectivity (ee s up to 91%) was observed in the Pd catalyzed ally lie animation reaction [86],... 

Sigmatropic rearrangement of dichlorophosphites, obtained from optically pure (+)-(7 )-2,2,6,6-tetramethyl-4-heptyn-3-ol and phosphorus trichloride, gives the optically pure (—)-( A/)-allenyldichlorophosphane oxide 3, which is hydrolyzed to the allenylphosphonic acid... 

Methyl chlorofluorophosphite, 4 141 analysis of, 4 143 Methyl dichlorophosphite, 4 63 Methyl difluorophosphite, 4 141 analysis of, 4 143 Methylgermanium oxide, 3 67 Methylgermanium sulfide, 3 67 Methylgermanium triiodide, 3 64 analysis of, 3 66... 

In the case of P(III) acid dichlorides, in which the electrophilicity of the phosphorus atom is increased in comparison with that of monochlorides, a decrease in the selectivity of N-phosphorylation must be expected. In fact, the reactions of indole and 2-methylindole with dichloroamidophosphites, dichlorophosphites, and dichlorophosphines lead to bisindolylphosphonites, bisindolylphosphines, and bisindolylphosphinites 18-20 [11,12]. 

The same paper [19] reports on the phosphorylation of 5-bromoisatin o-carboxyphenylhydrazone hydrochloride by ethyl dichlorophosphite, resulting in the synthesis (according to the author) of 3-[N-(2-alkoxy-6-oxobenzo[J]-l,3,2-oxoazophosphorin-3-yl)imino]isatin (54) ... 

Ethyl dichlorophosphite and methyl dichlorophosphite have been prepared by the reaction of 1 mol of the appropriate alcohol with 1 mol of phosphorus(III) chloride.1 The ethyl compound has also been prepared from triethyl phosphite and phosphorus(III) chloride.2 The method outlined below is essentially the former however, several improvements have been incorporated. Among the difficulties encountered in the preparation of these compounds are the following Side reactions occur between the generated hydrogen chloride and the ester, giving an alkyl chloride and phosphorous acid disproportionation may occur in the case of the ethyl ester, the necessary vacuum distillation causes losses of the relatively low boiling product. 

Central Research Department, Monsanto Chemical Company, Dayton, Ohio. (This author worked with ethyl dichlorophosphite.)... 

University of New Mexico, Albuquerque, N.M. (These checkers worked with methyl dichlorophosphite.)... 

Ethyl dichlorophosphite is a colorless liquid, with an irritating odor. It fumes when exposed to air. It has the following physical constants sp. gr., 1.30526 b.p., 117.5° n °, 1.47176. It decomposes at 165° to ethyl chloride, phosphorus, phosphine, and phosphoric acid.3 It reacts with water to form hydrogen chloride and phosphorous acid, and with alcohols to form esters. When ammonia is passed through ethyl dichlorophosphite, ethyl phospheni-midate (ethoxyphosphimide), C2H5OP=NH, is formed. 

Methyl dichlorophosphite hydrolyzes readily and fumes in air. It reacts rapidly with aqueous sodium hydroxide. Mercury is attacked slowly by the compound, as is Lubri-seal stopcock grease. It reacts with sublimed antimony-... 

Chloroethyl dichlorophosphite may also be prepared by allowing ethylene oxide to condense with phosphorus(III) chloride.1... 

The apparatus and procedure for the preparation of 2-chloroethyl dichlorophosphite are essentially the same as described for the analogous silicon and sulfuryl compounds (synthesis 30). One hundred thirty-seven and one-half grams of reagent-grade phosphorus (III) chloride (1.0 mol) is allowed to react with 80.5 g. of freshly distilled, anhydrous ethylene chlorohydrin (1.0 mol) in a 500-ml. flask under the conditions set forth in the cited synthesis. Approximately 1 hour is required for the introduction of the ethylene chlorohydrin. 

Chloroethyl dichlorophosphite is a colorless liquid having a specific gravity of 1.515 at 0°. It solidifies to a white solid at —142 1°. A second crystalline phase may be obtained by allowing the first phase to warm to room temperature. The higher-melting phase was not obtained directly from the liquid phase, nor was a definite temperature for the transition between the two phases observed. The boiling point has been reported to be 172 to 175° (747.8 mm.)1 and 162.4° (760 mm.).2... 

Chloroethyl dichlorophosphite fumes in moist air and hydrolyzes readily in water. It reacts vigorously with ethanol and propylene glycol and is soluble in dioxane, acetone, and diethyl ether. 2-Chloroethyl dichlorophosphite is obtained when the dichloride is allowed to react with antimony (III) fluoride at room temperature under a pressure of 50 mm. 

The mixture of reaction products is fractionally distilled in a modified Dufton column as described in synthesis 45. The yields based on methyl dichlorophosphite are chloro-fluorophosphite, about 8%, and difluorophosphite, about 40%. 

---