Phosphate and phosphorus chemistry

Studies of Alkali Phosphate and Phosphorus Chemistry Important to Magnetohydrodynamics Combustion... 

In tervalent phosphorus acid chemistry the main area of activity has again been the use of tervalent phosphorus acid derivatives for the preparation of phosphates or modified phosphates of biochemical interest. Apart from the nucleotide field, vide infra), pentavalent phosphorus acid chemistry seems to be mainly in the doldrums exceptions to this are the areas of myo-inositol phosphate and aminoalkylphosphonate chemistry where activity remains high. 

Phosphorus biochemistry is dominated by two phosphate esters, namely ATP and DNA. There are, however, many other P compounds (e.g. phosphoenzymes) which play a crucial role in metabolic processes. Phosphorus has more known biochemical functions in the body than any other single mineral element. If carbon compounds are regarded as the building blocks of life, phosphorus must surely be regarded as the site manager . Important non-bio parallels between carbon chemistry and phosphorus chemistry have been recognised in recent decades (Chapter 6). 

A. D. F. Toy, Phosphorus Chemistry in Pveydaj Piping, American Chemical Society, Washington, D.C., 1987. P. Becker, Phosphates and Phosphoric A.cid, 2nd ed., Marcel Dekker, Inc., New York, 1989. 

The phosphorus chemistry occurring in interstellar matter and in the circum-stellar regions of the cosmos is not yet understood. We do, however, know that phosphorus compounds are present in meteorites, lunar rocks and Mars meteorites. Oddly enough, the element can be detected nearly everywhere, though only in low concentrations. Phosphate minerals, as well as the anions PO2 and PO3, have... 

The study of [4.4.0] ring systems has resulted primarily from the study of various other aspects of phosphorus chemistry. An investigation into the effect of nitrogen donor action on the increase in coordination at phosphorus in a series of oxyphosphoranes led Holmes and co-workers <1998IC4945> to compounds 24 and 25. The compounds were fully characterized by NMR spectroscopy and X-ray diffraction. Compound 24 was heated for 30 min at 140°C in an NMR tube. The reaction was followed by 31P NMR spectroscopy which indicated that conversion to a phosphorane 26 and a small amount of phosphate had taken place (Equation 4). The pentaoxyphosphorane 25 was successfully produced via an oxidative addition reaction between the diol 27 and triphenyl phosphate in the presence... 

The equilibria among the species are dependent on the pH of the solution in much the same way as the equilibria among the various phosphate species (see Chapter 14). Not only is the formation of polyvanadates reminiscent of phosphorus chemistry, so is the fact that vanadium forms oxyhalides such as OVX3 and V02X. 

Hata, T. and Sekine, M., Silyl- and stannyl-esters of phosphorus oxyacids — intermediates for the synthesis of phosphate derivatives of biological interest, in Phosphorus Chemistry Directed Toward Biology, Stec, W.J., Ed., Pergamon, New York, 1980, p. 197. 

We have done a little lock and key chemistry with cyclodextrin imidazoles. For instance, Bovy (18) has prepared the cyclic phosphate derived from naphthalenediol (XI) and from a tetralindiol (XII). Both of these are hydrolyzed by our 6A,6D cyclodextrin bisimidazole (VII) but these substrates are hydrolyzed less effectively than is the f-butylcatechol cyclic phosphate (VIII). In XI and XII, the phosphorus atom will lie on the axis of the cavity, rather than displaced to one side as with t-butylcatechol, and in particular the attacking water mole-... 

The oxyanions of phosphorus and arsenic take up the major portion of a recent large volume of Gmelin (C9), which includes more than 100 compounds, hydrates and phases containing phosphate groups.263 To pursue the detail of the latter is an exercise in phosphorus chemistry, so we concentrate on a survey of the available data on the Mn" coordination polyhedra. 

Phosphorous is a five-valent element, and its natural oxide is P2O5, phosphorous pentoxide. It is a highly hygroscopic powder and readily reacts with water to form phosphoric acid (H3PO4). This acid when reacted with various aUcaline compounds forms phosphates. These and other modified compounds are linear or chain, cyclic or ring, and branch chain polymers. Because these compounds are polymeric, phosphates can provide a continuous structure and, hence, form good ceramics. The reader is referred to Topics in Phosphorus Chemistry by Westman [1] for details. Because of the variety of polymeric compounds formed by phosphorous, a systematic nomenclature is used in phosphate chemistry. 

Phosphorus has an even wider range of oxoacid chemistry, and a commensurately wide range of phosphates, phosphites, polyphosphates, hypophosphites, and so on of the alkali metals are preparable. Sodium and potassium are the most common cations used, largely because of their availability and low cost. The cation often has little effect on the properties and applications, which are covered in Phosphates Solid-state Chemistry. Most form a variety of crystalline hydrates, which have been well covered in previous treatments and need not be repeated here. Trae to form, lithium is the exception, forming no stable hydrates with phosphorus oxoanions. 

The chemistry of boron-phosphorus compouuds has been reviewed. Numerous boron-phosphorus derivatives have been reported, but relatively few boron-arsenic or boron-antimony compounds have been described. Boron-phosphorus compounds are similar in many ways to boron nitrogen derivatives, but the teudeucy to share boudiug electrons in covalent tetrahedral compounds is much more evident with phosphorus thau with uitrogeu. lu fact, most boron phosphorus chemistry iuvolves tetrahedral borou. They are typically either phosphiue-boraue complexes, such as R3P BR j, or phosphinoboranes (R2PBR2) , cyclic or polymeric derivatives of the hypothetical H3P BH3. The chemistry of these compounds and that of boron phosphate and thiophosphate is described below. Boron phosphides are discussed in Section 2.6. 

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