Dialkylphosphoric acid

Calcium/magnesium Dialkylphosphoric acid in aliphatic alcohol... 

Dialkyl peroxyphosphates 67 or monoperoxy phosphates 68 react with phenyhnagnesium bromide to afford tcrt-butyl phenyl ether in high yield together with dialkylphosphoric acid or alkylphosphoric acid in moderate yields (equation 102). 

Practical considerations call for a liquid of high viscosity and low vapour pressure and a low solubility in water. A solution of a calcium complex with a dialkylphosphoric acid (e.g. ((RO)2POO)2Ca, where R = C8Hi7 to C16H33) in a very polar solvent such as di-n-octylphenyl phosphate can be used in an ion-selective electrode that gives a linear response over 101 [Ca2+]... 

The same tendency has been observed for dialkylphosphoric acids (RO)2(HO)PO for example, the stability of HD/DP (R = wodecyl) was greater than that of HDEHP (R = ethylhexyl) (32) ... 

Solovkin, A.S., Lobanov, A.V., Rubisov, B.N. 1989. Mathematical model of distribution of dialkylphosphoric acids in water-nitric acid-organic solvent-trialkyl phosphate two-phase systems. Soviet Radiochem. 31(1) 113-119. (Translated from Radiokhimiya 31(1) 117-124.)... 

Phosphorylated aminomethylindoles 98 were obtained from 3-formylindoles 97a,b, amines, and hydrophosphoryl compounds [99-101] in the Kabachnik-Fields reaction [233-235]. As shown by DTA, 3-(hydroxyamino)methylindole is formed initially in the case of secondary amines and then it reacts with dialkylphosphorous acid. In the case of ammonia and primary amines imine is formed at the first stage and then it adds dialkylphosphorous acid. 

Alkyl phosphoric acids. Perhaps the largest single group of extractants for actinides are the alkylphosphoric acids of three main types dialkylphosphoric acids, dialkylphosphonic acids, and... 

In a polar solvent in which the dialkylphosphoric acid is primarily a monomer, trivalent actinide extraction has been described as (59) ... 

The dialkylphosphoric acid most commonly used and studied for trivalent actinide extraction is probably HDEHP. Even though this compound is not as strong an extractant as some other straight-chain analogs, it offers advantages such as low aqueous-phase solubility, less tendency to third-phase formation, and ready availability. 

The addition of an ether linkage in the alkyl chains of dialkylphosphoric acids has been found to increase its extractive power for trivalent actinides, resulting in an extractant that is more effective from acid solutions than is HDEHP (69). Bis(hexoxy-ethyl)phosphoric acid (HDHqEP) is a compound of this type that has been studied extensively (70,71). The ether linkage may contribute to the coordination of the metal ion, resulting in the formation of a seven-membered ring. 

In the extraction of trivalent actinides, the dialkylphosphonic acids behave in a manner similar to that observed for the dialkylphosphoric acids. However, in some systems, they offer a greater intergroup separation between lanthanides and actinides. The separation of Cf and Cm from nitric acid solutions has been studied using 2-ethylhexylphenylphosphonic acid [HEH( P)] and 1-methyl-heptylphenylphosphonic acid [HMeH( P)]. ORNL has developed a process for intergroup actinide separation, called Hepex, based on the use of HEH( P) (72,73). ... 

Razumov, A.L, and Moskva, V.V., Reaction of dialkylphosphorous acids with orthoformic esters, Zh. Obshch. Khim.. 34, 3125, 1964 J. Gen. Chem. USSR Engl. Transl.), 34, 3167, 1964. 

Pudovik, A.N., and Arbuzov, B.A., Addition of dialkylphosphorous acids (dialkyl phosphites) to unsaturated compounds. Part 2. Addition of dialkylphosphorous acids to acrylonitrile and to methyl methacrylate, Zh. Obshch. Khim., 21, 1837, 1951 Chem. Abstr, 46, 6082e, 1952. 

Practical considerations call for a liquid of high viscosity and low vapour pressure and a low solubility in water. A solution of a calcium complex with a dialkylphosphoric acid (e.g. ((RO)2POO)2Ca, where R = CgH to C16H33) in a very polar solvent such as di-n-octylphenyl phosphate can be used in an ion-selective electrode that gives a linear response over 10 [Ca +] 5 X 10. Solutions of Ni(phen)3 nitrate (or perchlorate, or tetrafluoroborate) in nitrobenzene of p-nitrocymene have been used as specific ion electrodes for nitrate (or perchlorate, or tetrafluoroborate). A mercury dithizonate electrode can be prepared which is ion-specific for mercury (II) and replaces the mercury drop electrode for the titration of Al, Ca, Cu, Hg , Ni and Zn with EDTA. Silver, lead and palladium dithizonates have also been used in titrimetry. ... 

The reaction of dialkyl chlorophosphates with 1,3-aminopropanol mainly furnished derivatives of the N-phosphorylation-y-hydroxypropylamide of dialkylphosphoric acid (5 = 9.0 ppm for R = Et 5 = 11.0 ppm for t-Pr) [105], The final product is stable and does not undergo isomerization resulting in the formation of corresponding phosphates, as in the case of the P-hydroxyethylamides of dialkylphosphates. This result indicates that the regioselectivity of this substitution (N-H versus O— H) correlates with the acidity of the corresponding protons. 

Kosyakov et al. studied the extraction of Pu(IV) and other actinides from nitric acid solutions by several dialkylphosphoric acids. Their results for Pu(IV) are shown in Fig. 11. The distribution coefficient increases as the length of the normal... 

Fig. 11. Extraction of Pu(IV) by dialkylphosphoric acids (0.5 M in isooctane) from HNOj solutions. 238...

Berthon, L., J. Muller, D. GuUlaumont, C. Berthon, and L. Couston. 2012. Spedation in solvent extraction systems containing a malonamide and a dialkylphosphoric acid Atalante 2012 scientific highlights. CEA Report, CEA-R-6298,201. 

Nature of cocktail materials in calcium ISEs. The electrochemical performances of calcium ISEs (and all other ISEs based on organic-type sensors) depend on the structure of the sensor as well as mediator. Thus, calcium ISEs fabricated from calcium salts of dialkylphosphoric acids depend on the solvent mediator, e.g. di-octylphenyl phosphonate (DOPP) yields a calcium ISE whereas decan-l-ol produces the so-called water hardness (or calcium/ magnesium) ISE. Several fundamental studies have been made on the molecular variation of these two critical constituents (13-21). 

Klement and Wild [37] have investigated numerous phosphate esters, using TLC in order to identify them with certainty in starting and end products of reactions. Good separation of even non-polar phosphorus compounds was also possible. Sihca gel G layers were used in the separation of ahphatic and aromatic esters of various phosphoric and phos-phoramidic acids and of the ammonium salts of dialkylphosphoric acids. Suitable solvents are fisted below ... 

Baes, C. F. 1962. The extraction of metallic species by dialkylphosphoric acids. J. Inorg. 

A linear dependence of the Am extraction constant on the surface activity of a number of dialkylphosphoric acids was established [20]. The minimum acid concentration in dodecane at which the limiting adsorption at the interface with 1 M nitric acid is attained served as a measure of the surface activity. 

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