Phosphorous acid diesters

HO A phosphoric acid monoester HO A phosphoric acid diester 0 1 R" A phosphoric acid triester A carboxylic acid ester... 

Phosphoric acid diesters are prepared by treating a liquid slurry of phosphate monoester with epoxides in the presence of alkali compounds. Thus a mixture of monolauryl phosphate sodium salt and triethyl amine in water was treated with glycidol at 80°C for 8 h to give 98% lauryl(2,3-dihydroxypropyl)phosphate sodium salt [13]. 

The outlined scheme can also be used to calculate the amount of phosphoric acid triesters. In that case the difference must be formed of the total phosphorus content minus that of free phosphoric acid, phosphoric acid monoester, and phosphoric acid diester. The resulting value is then multiplied with the calculated molecular mass of the triester. 

This property of organophosphate esters may be of environmental importance since phosphoric acid diesters are much more soluble and very little is known concerning the environmental toxicity of these compounds. The available data do not provide sufficient descriptions of the experimental methods to determine if the rates are reliable (Barnard et al. 1961 Ciba-Geigy 1984e, 1986 Howard and Deo 1979 Mayer et al. 1981 Wolfe 1980). The majority of reports provide only a minimum of information and exclude important facts such as the duration of the experiments and the concentration of buffers. Despite the lack of experimental detail, published rate constants for base-catalyzed hydrolysis appear to be reasonably consistent and suggest that the hydrolytic half-life of triphenyl phosphate will vary from... 

Sequence polypeptides were obtained by polycondensation of tauryl peptides and 3-aminopropansulfonylpeptides with the two phosphorous acid diester triazolides A and B [54]... 

Reaction of the tetrazolide of phosphorous acid diester with a S -protected thymidine and subsequent oxidation with iodine yields the corresponding thymidine phosphortriester [961... 

In this procedure a diacylglyceryl phosphate is first converted with CDI into a reactive phosphoric imidazolide, which is then treated with a labeled alcohol to give a labeled phosphoric acid diester 123... 

Diselenophosphates have been much less investigated than the analogous dithiophosphates, but some interesting chemistry was revealed. The reactions of phosphorus(V) selenide, P2Se5, with alcohols and phenols produce diseleno-phosphoric acid diesters, (RO)2P(Se)SeH, the parent compounds of di-selenophosphato anionic ligands. The free acids are not stable and should be immediately converted to metal salts or complexes. 

At the same time, however, the iridium-catalyzed hydrogenation of 80 was reported using chiral phosphoric acid diester 17be based on BINOL [47a]. Full conversion and a maximum e.e. of 50% was observed, again in a slow reaction. Interestingly, a catalyst based on palladium and 17be afforded 39% e.e. and full conversion in the hydrogenation of aryl imine 87. 

The propensity of the cesium salts of week acids to accelerate SN2 type displacement reactions was exploited for the stereodirected conversion of glycosyl nitrates into anomeric phosphotriesters by exposure of phosphoric acid diesters to cesium salts (Scheme 9).16 Thus, glycosyl nitrate 50, obtained by azidonitration of 3,4-di-O-acetyl-L-fucal, was treated with... 

Hydrolysis of Medicinal Phosphoric Acid Diesters and Triesters... 

Whereas there are relatively few phosphoric acid diesters of medicinal or toxicological interest, phosphoric acid triesters are of greater significance. Such compounds occur mainly as prodrugs, as discussed in the present section, or plasticizers and insecticides (see next section). 

Phosphoric acid, H3PO4, is a tribasic (three-protic) acid—i. e., it contains three hydroxyl groups able to donate H"" ions. At least one of these three groups is fully dissociated under normal physiological conditions, while the other two can react with alcohols. The resulting products are phosphoric acid monoesters (R-O-P(O)O-OH) and diesters (R-0-P(O)O-O-R ). Phosphoric acid monoesters are found in carbohydrate metabolism, for example (see p.36), whereas phosphoric acid diester bonds occur in phospholipids (see p. 50) and nucleic acids (see p. 82 ). 

If the phosphate residue of a nucleotide reacts with the 3 -OH group of a second nucleotide, the result is a dinucleotide with a phosphoric acid diester structure. Dinucleotides of this type have a free phosphate residue at the 5 end and a free OH group at the 3 end. They can therefore be extended with additional mononucleotides by adding further phosphoric acid diester bonds. This is the way in which oligonucleotides, and ultimately polynucleotides, are synthesized. 

Ribonucleic acids (RNAs) are polymers consisting of nucleoside phosphate components that are linked by phosphoric acid diester bonds (see p.80). The bases the contain are mainly uracil, cytosine, adenine, and guanine, but many unusual and modified bases are also found in RNAs (B). 

By far the most common form is B-DNA (2). As discussed on p. 84, this consists of two antiparallel polydeoxynucleotide strands intertwined with one another to form a right-handed double helix. The backbone of these strands is formed by deoxyribose and phosphate residues linked by phosphoric acid diester bonds. 

D Eon, J.C., Crazier, P.W., Furdui, V.I., Reiner, E.J., Libelo, E.L. and Mabury, S.A. (2009) Observation of a commercial fluorinated material, the polyfluoroalkyl phosphoric acid diesters, in human sera, wastewater treatment plant sludge, and paper fibers. Environ Sci Technol, 43, 4589-4594. 

OP compound - phosphoric acid diester - monoester - phosphoric acid. [ alcohol, thiol, or phenol, etc.] [+ ROH/RSH]... 

Homer-Wadsworth-Emmons reactions are C=C-forming condensation reactions between the Li, Na, or K salt of a /1-koto- or an a-(alkoxycarbonyl )phosphomc acid dialkyl ester and a carbonyl compound (see Figure 4.46). These reactions furnish a,/3-unsaturated ketones or 0 ,/3-unsaturated esters, respectively, as the desired products and a phosphoric acid diester anion as a water-soluble by-product. In general, starting from aldehydes, the desired compounds are produced /ra/ov-selectively or, in the case of alkenes with trisubstituted C=C double bonds, -selectively. 

DCC is also used in nucleotide chemistry to esterify a sugar hydroxyl group with a phosphate group in another nucleotide or oligonucleotide unit. Also p-styrene based polymers with a pyridyl-2-ethanol end group are reacted in pyridine with 3 -0-acetyl-desoxythimidine-5 -phosphate in the presence of DCC." The reaction of mono esters of phosphoric acid with alcohols or phenols, in the presence of DCC, affords phosphoric acid diesters in high yield." This reaction is widely used in nucleic acid chemistry. 

Monoesters of phosphoric acid 536, in the presence of DCC, react with alcohols and phenols to give the corresponding phosphoric acid diesters in quantitative yield. This reaction is widely used in nucleic acid chemistry. The first step in this reaction is the formation of the cyclic metaphosphate trimer 537, which serves as an active phosphorylating agent. ... 

A related reaction that yields the same types of products as does the Michaelis-Arbuzov reaction begins with either a phosphinous acid or a monoester of a phosphonous acid. (The corresponding reaction may also be performed with a diester of phosphorous acid.) By treatment with an appropriate base, the conjugate base of the phosphorus-containing acid is generated that serves as the nucleophihc reagent for direct formation of the phosphonate or phosphine oxide product (or phosphonate product from a phosphorous acid diester). This procedure is commonly referred to as the Michaehs Becker reaction. ... 

TeTy few investigations of the ligand properties of phosphorous acid diesters OP(H)(OR)2 have been reported, as shown in Table I. Molecules of this type are potentially interesting in that several coordination... 

Table L Complexes Containing Phosphorous Acid Diesters OP(H)(OR)2...

We wish to report several metal complexes formed from a phosphorous acid diester of the type OP (H) (OR) 2 which underwent isomerization to form a metal-phosphorus bond as in (a). In the course of our investigations on the complexing properties of polycylic phosphites (9 17) j it was found that 2,8,9-trioxa-l-phosphaadamantane (L) undergoes a rapid, acid hydrolysis in acetone to form two colorless, crystalline hydrolysates, A and B. Only isomer A or L complexed with divalent hydrated metal ions, and it is concluded from infrared evidence that A has isomerized as shown in the following reaction sequence. Supporting infrared and PNMR evidence is presented for the tentatively postulated structures of A and B. 

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