Sodium diethyl phosphite

Arbuzov, B.A., Vinogradova, V.S.. Polezhaeva. N.A., and Shamsutdinova, A.K., Esters of P-oxophos-phonic acids. Part 12. Structure of reaction products of some a-halo ketones of the aromatic series with tnethyl phosphite and diethyl sodium phosphite, Izv. Akad. Nauk SSSR, Ser Khim., 1380, 1963 Bull. Acad. Sci. USSR, Div. Chem. Sci. (Engl. Transl.), 1257, 1963. 

Arbuzov, B.A., and Lugovkin, B.P., Action of triethyl phosphite and diethyl sodium phosphite on some dihalo derivatives, Zh. Obshch. Khim., 21, 99, 1951 Chem. Abstr, 45, 7002e, 1951. 

Sodium-Ammonia, For the reduction of a phenol to an aromatic hydrocarbon a solution of the phenol and diethyl hydrogen phosphite in carbon tetrachloride is treated with triethylamine and allowed to stand for 24 hrs. for complete separation of triethylamine hydrochloride (1). The phenol diethyl phosphate ester is collected. 

Diethyl hydrogen phosphite, 31, 112 Diethyl malonate, 30, 70 Diethyl methylphosphonate, 31, 34 Diethyl o-nitrobenzoylmalonate, 30, 71 Diethyl sodium phthalimidomalonate, 30, 7... 

Partial control of enolate geometry occurs also when the enol phosphate, prepared by treatment of fluoroalkyl ketones with sodium diethyl phosphite, is... 

The following reaction sequence was used to obtain methyl hydroxymethanediphosphonic acid. This compound is widely used as a water hardness sequestering agent and detergent builder. Triethyl chloride was reacted with acetyl chloride to give diethylacetylphosphonate, followed by a conversion with diethyl phosphite and sodium. After completion of this reaction the substance was hydrolyzed with HC1 to yield hydroxymethanediphosphonic acid, [93,94], as shown in Eqs. (49)-(51) ... 

Another method for the preparation of hydroxyalkanephosphonic acids is the conversion of aldehydes with dialkyl phosphites in the presence of triethylamine or sodium methylate leading directly to the corresponding a-hydroxyalkane-phosphonates. This reaction is reversible, leading to the starting materials aldehyde and diethyl phosphite again [143,146]. 

The 9,10-phosphonostearic acid in form of its sodium salt shows a good thermal stability and was efficient as an inhibitor in rust protection. The diethyl-phosphonoacetoxystearic acid methyl ester is used as additive in high-pressure lubricants. Rust protection properties are also shown by 9,10-phosphonostearyl alcohol [157]. Trisodium 9,10-phosphonostearate possesses the best surface activity in an 0.2% aqueous solution showing 33 mN/m at 30°C and a pH value of 10.5 [156]. By the addition of dialkyl phosphite to a,p-unsaturated ketones the y-oxophosphonic acids are available [159]. Addition of dialkyl phosphite to y-ketoacids leads to a-hydroxy-y-carboxyphosphonates see Eq. (86) ... 

The rigid, planar pyridine analog 111 was isolated in low yield by first hydrolyzing the known (67) pyridine diethyl phosphonate 109 to the corresponding free acid 110 followed by permanganate oxidation (2). An alternative synthesis of 111 has recently been reported (68). Alkylation of pyridine-2-carboxylate -oxide with dimethylsulfate and subsequent reaction with the sodium salt of diethyl phosphite gave the triester 112, which was readily converted to 111. 

Schrader prepared the ester (38) in 60% yield by reaction of sodium p-nitrophenate with diethyl chlorophosphate, using xylene as solvent for the reaction. He made it, but in lower yields, from p-nitrophenol and diethyl chlorophosphate, using, respectively, pyridine and sodium cyanide as acceptors for hydrogen chloride. Schrader also prepared it in 96% yield by nitrating diethyl phenyl phosphate at 0° C. or below. Under the conditions he used, Schrader claims that the nitro group is directed to the para position. No yield is given for the diethyl phenyl phosphate, which he presumably made from sodium phenate and diethyl chlorophosphate. Diethyl chlorophosphate may be prepared in high yield (30) from diethyl phosphite and chlorine. 

The broad use of A -carbonyldiimidazole (CDI) for the synthesis of amide and peptide linkages became a routine method only in the early sixties. JV-Protected amino acids were treated at room temperature with an equimolar amount of CDI to give imidazolides. Anhydrous tetrahydrofuran, dimethoxyethane, dichloromethane, pyridine, dimethylfor-mamide, and diethyl phosphite were utilized as solvents. In the second step the esters of amino acids, their hydrochlorides, or sodium salts were added to yield the peptide after several minutes or hours of reaction time. 

Preparation of diethyl 3,3-diethoxypropynyl-l-phosphonate — Reaction of a sodium salt of a dialkyl phosphite with an acetylenic halide492... 

R)-aluminum-lithium-BINOL complex (0.024 g, 0.04 mmol) was dissolved in toluene (0.4 ml), and to this solution was added dimethyl phosphite (0.044 g, 0.4 mmol) at room temperature the mixture was stirred for 30 min. Benzaldehyde (0.042 g, 0.4 mmol) was then added at -40°C. After having been stirred for 51 h at -40°C, the reaction mixture was treated with 1 N hydrochloric acid (1.0 ml) and extracted with ethyl acetate (3 x 10 ml). The combined organic extracts were washed with brine, dried over sodium sulfate, and concentrated under reduced pressure. The residue was purified by flash chromatography (silica, 20% acetone/hexane) to give the diethyl (S)-a-hydroxybenzylphosphonate (78 mg, 90%) with 85% enantiomeric excess as a colorless solid of mp 86 to 87°C. 

In passing, it may be noted that we prepared diethyl 2-fluoroethylphosphonate (III) and diethyl benzylphosphonate (IV) by an alternative route from sodium diethyl phosphite and the corresponding halides.6... 

This type of reaction was originally carried out with ethyl iodide1 and has been extended to other alkyl halides,2 halogeno-carboxylic esters3 and to substituted arsine halides.4 Incidentally when p-toluene sulphonyl chloride and naphthalene-2-sulphonyl chloride were allowed to react with sodium diethyl phosphite, the corresponding disulphones were obtained in small yield.5... 

Among phosphorus insecticides containing also nitrogen and sulphur we may mention 00 -diethyl-/S-/ -diethylaminoethyl phosphorothiolate (X). It was prepared (i) from diethyl phos-phorochloridate1 and sodium / -diethylaminoethyl mercaptide, (ii) from sodium diethyl phosphite and / -diethylaminoethyl thiocyanate, (iii) by the isomerization of OO -diethyl-O"-/ -diethylaminoethyl phosphorothionate (XI) obtained from / -diethylaminoethoxide and diethyl phosphorochloridothionate. 

A 1 M or 2 M solution of sodium ethylate in ethanol was added dropwise at 60°C to a 1 1 mixture of acetamidomethylenemalonate (1568) and diethyl phosphite, while the temperature of the reaction mixture was raised to 100°C. At this temperature, the reaction mixture was stirred for 1.0-1.5 hr [76RC661 88JCS(P1)61]. If the mixture was hydrolyzed with boiling concentrated hydrochloric acid overnight, 3-amino-3-phosphonopropionic acid (1572) was obtained in 75% yield (76RC661). When the cooled reaction mixture was treated with diethyl ether, then again boiled and filtered, and... 

A cation arriving with a nncleophilic anion is another important factor. The nucleophile can attack the substrate in the form of a free ion or an ionic pair. As a rule, lithium salts are less reactive than sodium and potassium salts. Russell and Mndryk (1982) reported several examples of this. The sodium salt of ethyl acetylacetate reacts with 2-nitro-2-chloropropane in DMF yielding ethyl 2-(wo-propylidene) acetylacetate. Under the same conditions, the lithium salt does not react at all. Potassium diethyl phosphite interacts with l-methyl-l-nitro-l-(4-toluylsulfonyl)propane in THF and gives diethyl 1-methyl-l-nitro-l-phosphite. The lithinm salt of the same reactant does not react with the same substrate in the same solvent. 

Method B (general procedure). Finely powdered Te (0.128 g, 1.0 mmol) is treated with an EtOH solution of sodium diethyl phosphite (1.5 mmol) in an apparatus which has been previously evacuated and flushed with argon. After a clear solution has formed, the a-haloketone (1.0 mmol) in dry EtOH or THE (2.0 mL) is injected. The mixture is stirred (25 or 80°C, 1-15 h) and then filtered through Celite with the aid of ether. The orange filtrate is evaporated at room temperature under vacuum (water pump) and the residue applied to an Si02 column, proceeding to elution (hexane/EtOAc) only after 30 min, to... 

A comparison of the suitability of solvents for use in Srn 1 reactions was made in benzenoid systems46 and in heteroaromatic systems.47 The marked dependence of solvent effect on the nature of the aromatic substrate, the nucleophile, its counterion and the temperature at which the reaction is carried out, however, often make comparisons difficult. Bunnett and coworkers46 chose to study the reaction of iodoben-zene with potassium diethyl phosphite, sodium benzenethiolate, the potassium enolate of acetone, and lithium r-butylamide. From extensive data based on the reactions with K+ (EtO)2PO (an extremely reactive nucleophile in Srn 1 reactions and a relatively weak base) the solvents of choice (based on yields of diethyl phenylphosphonate, given in parentheses) were found to be liquid ammonia (96%), acetonitrile (94%), r-butyl alcohol (74%), DMSO (68%), DMF (63%), DME (56%) and DMA (53%). The powerful dipolar aprotic solvents HMPA (4%), sulfolane (20%) and NMP (10%) were found not to be suitable. A similar but more discriminating trend was found in reactions of iodobenzene with the other nucleophilic salts listed above.46 Nearly comparable suitability of liquid ammonia and DMSO have been found with other substrate/nucleophile combinations. For example, the reaction of p-iodotoluene with Ph2P (equation (14) gives 89% and 78% isolated yields (of the corresponding phosphine oxide) in liquid ammonia and DMSO respectively.4 ... 

F. Zecchini gave for the refraction eq. 26-04 with the / -formula, and 15-17 with the /i2-formula. 0. Stelling measured the X-ray K-absorption spectrum of phosphorous acid, and of its salts and di-esters, and found that the results agree with the assumption that the phosphorus is tervalent with the solids, and tautomeric quinque- and ter-valent in soln. Phosphorous acid, the di-esters, methyl phosphorous acid, and ferric monopropyl phosphate have the structure RO)2 PO.H sodium diethyl phosphite, (C2H50)2 PO.Na silver diethyl phosphate, (C2H50)2 PO.OAg and monoacetyl phosphorous acid ... 

The influence of various phosphorus-containing modifiers, i.e. diethyl phosphite (I), the sodium salt of diethyl phosphite (II) and the disodium salt of 1,2-dicarbomethoxyethylphosphonic acid (III), on the transesterification, polycondensation and side reactions were examined. 

The studies carried out on the alcohol distillate obtained from the co-transesterification of dimethyl terephthalate with ethylene glycol in the presence of the sodium salt of diethyl phosphite or the di-sodium salt of 1,2-dicarbomethoxyethylphosphonic acid in various concentrations showed (Table I) that the side reactions were markedly suppressed. 

The results obtained (Table II) indicate that the precondensates modified with sodium salt of diethyl phosphite leads to a resin of following structure (3) ... 

With the sodium salt of diethyl phosphite as modifier the diethylene glycol content is within 0.13 to 2.6% against 1.5 to 2.0% for the un-modified resin. 

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