Phosphoric ester salts

Chem. Descrip. Ketoxime and phosphorous ester salt-based in solvents... 

In addition to their poor solubility in water, alkyl phosphate esters and dialkyl phosphate esters are further characterized by sensitivity to water hardness [37]. A review of the preparation, properties, and uses of surface-active anionic phosphate esters prepared by the reactions of alcohols or ethoxylates with tetra-phosphoric acid or P4O10 is given in Ref. 3. The surfactant properties of alkyl phosphates have been investigated [18,186-188]. The critical micelle concentration (CMC) of the monoalkyl ester salts is only moderate see Table 6 ... 

Treating petroleum oils with 3-5% calcium alkyl salicylate and 0.5-3% triethanolamine salts of phosphoric acid esters and ethoxylated dodecyl alcohol increases oxidation-thermal stability at 180-200°C in the manufacture of oil for metal parts quenching. The agent provides also short-term anticorrosion protection of the hardened articles [261]. Phosphoric acid salt alkyl esters are used in anticorrosives and aqueous dispersions in waterborne polyester coatings for metals [244]. 

Cyclic phosphoric esters, especially adenosine 3, 5 -monophosphate (cAMP) and to a lesser extent guanosine 3, 5 -monophosphate (cGMP), are ubiquitous intracellular secondary messenger substances which play an important role in biochemistry. X-ray structures and NMR data have been reported and their conformations are shown in Figure 2 (see also an X-ray structural determination of the sodium salt (82JA3398)). 

Phosphorus oxychloride is a suitable reagent for preparation of the symmetrically substituted phospho-triesters of type (RO)3PO. The preparation is easily achieved by treatment of phosphorus oxychloride with 3 equiv. of alcohols or their metal salts. The reaction is generally promoted by a base or acid. Titanium trichloride is a particularly effective catalyst for the reaction. Conversion of POCI3 to unsymmetri-cally substituted phosphotriesters is achievable with difficulty. Phosphorochloridates and phosphorodichloridates have been used for the preparation of mixed tertiary phosphoric esters of type (ROlmPOfOROn (ffi = 1, n = 2, or m = 2, n = 1) in a very wide variety. Reaction of phosphorus oxychloride and 1 or 2 equiv. of alcohols followed by hydrolysis forms phosphomonoesters or phosphodi-esters, respectively. The hydrolysis may be generally effected by dilute aqueous alkali. Some phosphoFodichlori te intermediates are easily hydrolyzed by water. For example, the phosphorylation of a ribonucleoside (1 equation 4) with phosphorus oxychloride in an aqueous pyridine-acetonitrile mixture furnishes the nucleoside S -monophosphate (2) in excellent yield. ... 

Replacement of H in H3PO4 by a radical R gives substituted phosphoric acids 0P(0H)20R and OP(OH)(OR)2 and finally the phosphoric ester, OP(OR)3. The structure of dibenzylphosphoric acid, HP02(0CH2C6Hs)2, was described in Chapter 8 the molecules are linked in pairs by O-H-0 bonds as in dimers of carboxylic acids. Examples of mono- and di-substituted ions are the phenyl-phosphate ion, (h), studied in the K salt, and the diethylphosphate ion, (i), in the Ba salt, and of an ester, triphenylphosphate,... 

Finally, sol-gel processing is widely used in the exploration of methods to prepare biomaterials for example, hydroxyapatite prepared from triethyl phosphite and calcium salts.237,238 Phosphate sol-gel synthesis is more difficult than for silicates since phosphoric esters are very difficult to hydrolyze 239... 

An entirely different ester is D-fructosyl phosphate, both ring forms of which, (14) and (15), were synthesized, isolated, and identified. Important as a possible intermediate in the biochemical synthesis and breakdown of the fructans, the pyridine salt of the 1-phosphate (12) was treated with dicyclohexylcarbodiimide, to form the cyclic 1,2-ester (13), which is very labile and is hydrolyzed to a mixture of both forms, (14) and (15), of the 2-phosphoric ester. This cycUzation mechanism was first mentioned by Khorana and coworkers, and later confirmed. Separation was effected... 

Thiamine monophosphate ester phosphoric acid salt Urn-beon. Ci3H N408PjS mol wt 442.35. C 32.58%, H 4.56%, N 12.67%, O 28.94%, P 14.00%, S 7.25%. Obtained by boiling an aq soln of thiamine triphosphoric acid ester for 2 hrs Velluz et al.. Bull. Soc. Chim. France 15, 871 (1948) from thiamine phosphoric acid ester chloride hydrochloride by ion exchange Zima et al., E. Merck s Jahresber. 67, 10... 

In the absence of a catalytic amount of Lewis acids such as Mg(OTf)2, weak Bronsted acids, such as thioureas, BINOL, and BINOL-derived phosphoric acids, could not promote this reaction alone. The reaction could not proceed with phosphoric acid salts, suggesting that the use of free acid is essential for effective catalysis. The combination of chiral phosphoric acid 13e and Lewis acid Mgp2 (4 1 ratio) was identified to be the optimal catalyst for the AFC alkylation reactions of phenols with p,y-unsaturated a-keto esters, affording the alkylation product in good yields with up to 99% ee. Not only free phenols but also indoles could be successfully applied in AFC reactions with P,y-unsaturated a-keto esters under the binary-acid catalysis (82-94% ee). 

Phosphoric acid, 1,3-phenylenetetraphenyl ester. See Resorcinol bis (diphenylphosphate) Phosphoric acid, pure. See Phosphoric acid Phosphoric acid, salts with N-[3-(dimethylamino) propyl] tetradecanamide. See Myristamidopropyl dimethylamine phosphate Phosphoric acid sodium aluminum salt, basic. See Sodium aluminum phosphate basic Phosphoric acid, strontium salt. See Strontium phosphate. 

ANIONIC SURFACTANTS Carboxylic acid salts Sulfonic acid salts Sulfuric acid ester salts Phosphoric and polyphosphoric acid esters Perfluorinated anionics... 

Some reactions between alkyl silanes and phosphoric acid, or its alkyl ester salts, can yield complex mixtures of products which include high polymers. Some of the better defined reactions in this category include (9.265) through (9.268)... 

A phosphoric ester metal salt nucleating agent which is easily dispersible in a crystalline polymer and effective in improving transparency and mechanical strength of the crystalline polymer is used in wire coating material. ... 

An aromatic phosphoric acid ester salt (lrgastab NAll, sodium salt of acyclic methylene bis[2,4-di-tert-butylphenol] phosphate) is a nucleating agent for polypropylene and a flame retardant for PC. ... 

Levorato, C., and Cima, L. (1968). Thin-layer chromatography and determination of thiamine salts, phosphoric esters, disulfides, and their respective thiochromes. J. Chromatogr. 32 11]-173. 

A soln. of picryl chloride in acetonitrile added dropwise to a soln. of adenosine-5 -phosphoric acid and tri-n-butylamine in methanol-pyridine, and the product isolated as the NH4-salt after 2 hrs. at room temp. ammonium methyl adenosine-5 -phosphate. Y 84%.— The soln. remains homogeneous and no precipitates are formed, such as ureas when carbodiimides are used as reagents. F. e., also pyrophosphoric and cyclic phosphoric esters, s. R. Wittmann, B. 96, 2116 (1963). 

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