Phosphorous acid, dialkyl esters, addition

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 ... 

Sulfuric acid (or phosphoric acid) is preferred as an acid catalyst for addition of water to alkenes because the conjugate base, HSO40 (or H2P04e), is a poor nucleophile and does not interfere in the reaction. However, if the water concentration is kept low by using concentrated acid, addition occurs to give sulfate (or phosphate) esters. The esters formed with sulfuric acid are either alkyl acid sulfates R—0S03H or dialkyl sulfates (R0)2S02. In fact, this is one of the major routes used in the commercial production of ethanol and... 

The unsaturated character of these trialkyl esters was shown by the ease with which they were attacked by nitric acid, but still more clearly by the formation, with evolution of heat, of stable crystalline addition compounds when they were mixed with cuprous halides. Thus CuC1.P(OC2H5)3 was described as consisting of colourless crystals melting at 190° to 192° C. and soluble in organic solvents.4 This property they share with phosphine, alkylphosphines and phosphorus trihalides. The phosphoric esters were quite indifferent to cuprous halides. Nor were such addition compounds formed either by phosphorous acid itself or by the dialkyl esters, which may show that the latter compounds have the unsymmetrical formula. Phosphorous acid probably exists in both forms, but first as P(OH)3, i.e. when produced from PC13 and Ha0.5 This may be transformed into the unsym-metrieal form through an addition compound HC1.P(0H)3,4 and probably also exists in the form of complex molecules, such as... 

PPS doped with AsFs dissolves readily in AsFs, but cast films are no longer soluble. Frommer has suggested that the solubilization mechanism involves solvation of both reactive radical intermediates and dopant counterions.f In addition, dialkyl esters of phosphoric acid dope PANi and render it soluble in certain solvents such as decalin. The resulting solutions can be mixed with conventional polymers and used to prepare films and fibers. 

Pudovik, A.N., Moshkina, T.M., and Konovalova, I.V., New method of synthesis of esters of phosphonic and thiophosphonic acids. Part 31. Addition of phosphorous and hypophosphorous acids, dialkyl hydrogen phosphites, and esters of phosphonoacetic acid to esters of maleic acid, Zh. Obshch. Khim., 29, 3338, 1959 Chem. Abstr, 54, 152231, 1960. 

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