ChemInform Abstract: CHEMISTRY OF PHOSPHOROUS ACID- NEW ROUTES TO PHOSPHONIC ACIDS AND PHOSPHATE ESTERS

1978 ◽  
Vol 9 (31) ◽  
Author(s):  
D. REDMORE
Keyword(s):  
Phosphorous Acid ◽  
Phosphate Esters ◽  
Phosphonic Acids

scholarly journals Phosphonic acid: preparation and applications

2017 ◽  
Vol 13 ◽  
pp. 2186-2213 ◽  
Author(s):  
Charlotte M Sevrain ◽  
Mathieu Berchel ◽  
Hélène Couthon ◽  
Paul-Alain Jaffrès
Keyword(s):  
Phosphonic Acid ◽  
Functional Group ◽  
Phosphinic Acid ◽  
Phosphorous Acid ◽  
Direct Methods ◽  
Phosphonic Acids ◽  
Research Fields ◽  
Dialkyl Phosphonates ◽  
Review Reports ◽  
Acid Functional Group

The phosphonic acid functional group, which is characterized by a phosphorus atom bonded to three oxygen atoms (two hydroxy groups and one P=O double bond) and one carbon atom, is employed for many applications due to its structural analogy with the phosphate moiety or to its coordination or supramolecular properties. Phosphonic acids were used for their bioactive properties (drug, pro-drug), for bone targeting, for the design of supramolecular or hybrid materials, for the functionalization of surfaces, for analytical purposes, for medical imaging or as phosphoantigen. These applications are covering a large panel of research fields including chemistry, biology and physics thus making the synthesis of phosphonic acids a determinant question for numerous research projects. This review gives, first, an overview of the different fields of application of phosphonic acids that are illustrated with studies mainly selected over the last 20 years. Further, this review reports the different methods that can be used for the synthesis of phosphonic acids from dialkyl or diaryl phosphonate, from dichlorophosphine or dichlorophosphine oxide, from phosphonodiamide, or by oxidation of phosphinic acid. Direct methods that make use of phosphorous acid (H3PO3) and that produce a phosphonic acid functional group simultaneously to the formation of the P–C bond, are also surveyed. Among all these methods, the dealkylation of dialkyl phosphonates under either acidic conditions (HCl) or using the McKenna procedure (a two-step reaction that makes use of bromotrimethylsilane followed by methanolysis) constitute the best methods to prepare phosphonic acids.

Selective retention of organic phosphate esters and phosphonates on aluminium oxide

1986 ◽  
Vol 6 (5) ◽  
pp. 477-483 ◽  
Author(s):  
M-A. Coletti-Previero ◽  
M. Pugnière ◽  
H. Mattras ◽  
J. C. Nicolas ◽  
A. Previero
Keyword(s):  
Aqueous Solution ◽  
Aluminium Oxide ◽  
Organic Phosphate ◽  
Phosphate Esters ◽  
Phosphonic Acids ◽  
Experimental Conditions ◽  
Phosphate Compound ◽  
Phosphorylated Compounds ◽  
Selective Retention ◽  
Inorganic Phosphates

Compounds containing the −PO3H2 function, such as monoesters of phosphoric acid and phosphonic acids, specifically bind to aluminium oxide in aqueous solution under experimental conditions where non-phosphorylated compounds are completely desorbed. The bound organic phosphate can be specifically displaced by aqueous solution of inorganic phosphates thus allowing their separation or detection by a technique similar to that of affinity chromatography. The consequences of this finding for phosphate compound biochemistry are discussed.

Tautomerization equilibria for phosphorous acid and its ethyl esters, free energies of formation of phosphorous and phosphonic acids and their ethyl esters, and pKa values for ionization of the P—H bond in phosphonic acid and phosphonic esters

1979 ◽  
Vol 57 (2) ◽  
pp. 236-239 ◽  
Author(s):  
J. Peter Guthrie
Keyword(s):  
Aqueous Solution ◽  
Free Energy ◽  
Equilibrium Constants ◽  
Phosphorous Acid ◽  
Triethyl Phosphite ◽  
Ethyl Esters ◽  
Free Energies ◽  
Phosphonic Acids ◽  
Hydroxy Compounds ◽  
Energy Relations

From data in the literature the free energies of formation in aqueous solution of triethyl phosphite and diethyl phosphonate can be calculated as −138.4 ± 1.7 and −165.1 ± 2.0 kcal mol−1, respectively. From these values, by application of free energy relations which we have published, the free energies of formation of the corresponding hydroxy compounds can be calculated and thence the equilibrium constants for tautomerization, which are 107.2, 108.7, and 1010.3 in favor of the tetracoordinate phosphonate tautomer for P(OEt)2OH, P(OEt)(OH)2, and P(OH)3, respectively. Using estimated pKa values for the tricoordinate phosphite species the tautomerization equilibria for the anions could also be calculated, as could the pKa values from the P—H bonds: 13, 26, and 38 for H—PO(OEt)2, H—PO2(OEt)−, and H—PO32−, respectively.

Substituent Effects on the Thermal Decomposition of Phosphate Esters on Ferrous Surfaces

2019 ◽  
Author(s):  
James Ewen ◽  
Carlos Ayestaran Latorre ◽  
Arash Khajeh ◽  
Joshua Moore ◽  
Joseph Remias ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Film Formation ◽  
Substituent Effects ◽  
Vapour Phase ◽  
Industrial Applications ◽  
Phosphate Esters ◽  
Antiwear Additives ◽  
Formation Mechanisms ◽  
Phosphate Ester ◽  
Wide Range

<p>Phosphate esters have a wide range of industrial applications, for example in tribology where they are used as vapour phase lubricants and antiwear additives. To rationally design phosphate esters with improved tribological performance, an atomic-level understanding of their film formation mechanisms is required. One important aspect is the thermal decomposition of phosphate esters on steel surfaces, since this initiates film formation. In this study, ReaxFF molecular dynamics simulations are used to study the thermal decomposition of phosphate esters with different substituents on several ferrous surfaces. On Fe<sub>3</sub>O<sub>4</sub>(001) and α-Fe(110), chemisorption interactions between the phosphate esters and the surfaces occur even at room temperature, and the number of molecule-surface bonds increases as the temperature is increased from 300 to 1000 K. Conversely, on hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>, most of the molecules are physisorbed, even at high temperature. Thermal decomposition rates were much higher on Fe<sub>3</sub>O<sub>4</sub>(001) and particularly α-Fe(110) compared to hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>. This suggests that water passivates ferrous surfaces and inhibits phosphate ester chemisorption, decomposition, and ultimately film formation. On Fe<sub>3</sub>O<sub>4</sub>(001), thermal decomposition proceeds mainly through C-O cleavage (to form surface alkyl and aryl groups) and C-H cleavage (to form surface hydroxyls). The onset temperature for C-O cleavage on Fe<sub>3</sub>O<sub>4</sub>(001) increases in the order: tertiary alkyl < secondary alkyl < primary linear alkyl ≈ primary branched alkyl < aryl. This order is in agreement with experimental observations for the thermal stability of antiwear additives with similar substituents. The results highlight surface and substituent effects on the thermal decomposition of phosphate esters which should be helpful for the design of new molecules with improved performance.</p>

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