Phosphoric acid diester anion

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. 

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. 

Hydrolysis appears to be the most important abiotic degradative mechanism for organophosphate esters under basic pH conditions. Under neutral and acidic conditions, the reaction slows considerably and could become an insignificant removal mechanism. The hydrolysis proceeds by a stepwise mechanism in which one alcohol group is removed at a time. The first step is cleavage of a P-OR bond (where "R" is an aryl or alkyl group) to produce a diester of phosphoric acid, which, under basic conditions, becomes an anion. 

The so-called "trapped sites" of classical mobile-site, liquid ion exchanger electrodes belong to a category of compounds known as ion association extractants. Examples are long-chain diesters of phosphoric acid and tricaprylylmethylammonium (Aliquat) ions. The latter cation was studied extensively by Freiser and co-workers (1-3 ) in the design of anion sensors. 

Phosphatidylserine, as expected, exhibited a more complex titration pattern. At pH 7.0, the diester phosphoric acid and carboxyl groups were in the anionic form, whereas the a-amino group had a positive charge. Below pH 4.5, phosphatidylserine is in the zwitterion form. Interestingly, this compound, as isolated from several different tissues, usually contains 1 mol of a monovalent cation per mole of phosphoglyceride. 

Ion-pair extraction and IPC were combined to analyze phosphoric acid mono- and diesters originating from the microbial hydrolysis of flame retardants. Even tertiary treatment did not ensure complete removal of the studied compounds detected in municipal wastewater [107], Chlorophenols extracted from water samples as anionic chlorophenolates were studied by IPC because the anionic forms of these analytes provide better UV ultraviolet absorption than uncharged chlorophenol based on their auxochromic effects. IPC conditions yielded adequate retention of the charged analytes and good sensitivity [108]. 

Monoalkyl phosphate and phosphate esters are special types of phosphoms-contain-ing anionic surfactants that are of great industrial importance. They are used for flameproofing, as antistatic for textiles, for foam inhibition, as an extreme pressure (EP) lubricant additive, as a surfactant component for alkaline, and as acid cleaners and for special cosmetic preparations (5). The commercially available phosphate ester products are complex mixtures of monoester and diester, free phosphoric acid, and free nonionic. 

The more readily accessible diesters can replace the triesters of phosphorous acid in the preparation of phosphonic diesters. The alkylation of the diesters, which must be presented as anions, by primary alkyl halides occurs exclusively on the phosphorus atom (Michaelis-Becker reaction). 

Dicesion dichloride. See Cesium chloride Dicesion difluoride. See Cesium fluoride Dicesium carbonate. See Cesium carbonate Dicesium diiodide. See Cesium iodide Dicesium sulfate. See Cesium sulfate Diceteareth-10 phosphate Definition Complex mixture of diesters of phosphoric acid and ceteareth-10 Properties Anionic... 

Definition Complex mixt. of diesters of phosphoric acid and C12-15 pareth-2 Properties Anionic... 

Definition Complex mixt. of diesters of phosphoric acid and a syn. C12-15 ethoxylated alcohol with avg. 8 moles EO Properties Anionic Toxicology TSCA listed Uses Surfactant, emulsifier, stabilizer, dispersant, corrosion inhibitor, detergent for cosmetics, pharmaceuticals, agric., industrial applies. 

TRYFAC Phosphate Esters are proprietary anionic surfactants prepared by the phosphation of various types of nonionic alcohols, ethoxylated alcohols and ethoxylated alkyl phenols. The finished products are a blend of raonoester and diester with slight amounts of free or unreacted phosphoric acid and nonionic. TRYFAC Phosphate Esters are available as either the free acid form (not neutralized) and/or the potassium salt. 

Chem. Descrip. Phosphoric acid mono- and dIester and alkylphenoxy Ionic Nature Anionic Uses Emulsifier for Vapona Properties Liq. 

The salts of mono- and diesters of phosphoric acid with fatty alcohol or their ethoxylates are anionic - surfactants. The water solubility and acid strength of such partial esters decrease with increasing chainlength. However, the sodium salts have good solubility. They are resistant to water hardness and to - hydrolysis, especially in alkaline media. They have good wetting and emulsifying properties. 

The esters of phosphorus-based acids constitute a relatively uniform group of anionic surfactants that can fill a special role in the overall scheme of surfactant applications. The esters and diesters of phosphoric acid have the general formula... 

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