Phosphorus compounds utilization

Typically, intense chemiluminescence in the UV/Vis spectral region requires highly exothermic reactions such as atomic or radical recombinations (e.g., S + S + M - S2 + M) or reactions of reduced species such as hydrogen atoms, olefins, and certain sulfur and phosphorus compounds with strong oxidants such as ozone, fluorine, and chlorine dioxide. Here we review the chemistry and applications of some of the most intense chemiluminescent reactions having either demonstrated or anticipated analytical utility. 

We begin, however, with a brief consideration of a group of phosphorus compounds of significance for their utility in the formation of carbon-phosphorus bonds via reaction with organometallic reagents in displacement reactions. 

Many thousands of phosphorus compounds have been described as having flame-retardant utility. The compounds demonstrating commercial utility arc much more limited in number. They include inorganic phosphorus compounds [red phosphorus, ammonium phosphates. insoluble ammonium polyphosphate, phosphoric acid-bascd systems for cellulosics). additive organic phosphorus flstme retardants... 

Cembella A. D., Antia N. J., and Harrison P. J. (1984a) The utilization of inorganic and organic phosphorus compounds as nutrients by eukaryotic microalgae a multidisciphnary perspective. Part 1. CRC Crit. Rev. Microbiol. 10, 317-391. 

Utilization of phosphate monoesters by microalgae and bacteria is effected by phosphomonoesterases (phosphatases) of broad specificity present at the cell surface. Hydrolytic release of PO4- from sugar phosphates, nucleotide phosphates, phospholipids, and phenyl phosphates, to name a few, enables a wide variety of phosphorus containing compounds to be utilized as phosphorus sources for growth of microbes. Ultrastructural observations and results from biochemical experiments indicate that extracellular phosphatases cleave the phosphate moiety from dissolved organic phosphorus compounds, which is then internalized, leaving the carbon skeleton outside the cell (Kuenzler and Perras, 1965 Doonan and Jensen, 1977). 

Use of d Orbitals.1 In addition to the ability of the S-Po elements to utilize d orbitals in hybridization with s and p orbitals so as to form more than four a bonds to other atoms, sulfur particularly and also selenium appear to make frequent use of dn orbitals to form multiple bonds. Thus, for example, in the sulfate ion, where the s and p orbitals are used in a bonding, the shortness of the S—O bonds suggests that there must be considerable multiple-bond character. The only likely explanation for this is that empty dn orbitals of sulfur accept electrons from filled pn orbitals of oxygen (see page 143). Similar dn-pn bonding occurs in some phosphorus compounds, but it seems to be more prominent with sulfur, and many instances will be cited later in this Chapter. 

Organophosphorus compounds (OPs) are utilized on a large scale as flame retarding agents and plasticizers in a variety of products, such as plastic materials, rubbers, varnishes, lubricants, hydraulic fluids, and other industrial applications. This family of chemicals consists of alkylated and arylated phosphate or phosphonate esters and related compounds such as phosphites, phosphines, and related dimeric forms as well as ionic forms (Figure 31.2). " The low volatility of phosphoric acid and derivatives makes it the preferred choice of the phosphorus based FRs. These FRs are most effective in polymers that char readily. Also halogenated phosphate esters, such as tris(l-chloroisopropyl) phosphate (TCPP), and tris(2-chloroethyl) phosphate (TCEP), are widely used. These combine the properties of both the halogen and the phosphorus compounds. 

Today s thermionic detectors are quite reliable and quantitative devices. A key to long-term stability and quantitative reproducibility seems to have been the utilization of an externally-heated alkali source [118]. The explanation of nitrogen detection based on the interaction of cyano radicals with the excited rubidium atoms [118] appears quite plausible, while the nature of response to phosphorus compounds still seems obscure. 

The rapid growth of studies of p - bonded and P " phosphorus compounds has continued during the past year and much early confusion has been explained. Many new systems have been synthesized utilizing the now well-established principle of the presence of bulky substituents at the multiple bonds to prevent oligomerization. 

Introduction - It is gratifying to report that interest in hypervalent phosphorus chemistry has been maintained, especially with regard to structural studies and the synthetic utility of pentaco ordinate phosphorus compounds. A novel departure has appeared in the area of hexaco-ordinate phosphorus with the synthesis of further phosphorus derivatives of the porphyrin ring system containing hypervalent phosphorus coordinated by the tetrapyrrole unit. The chapter will take its usual format, however, and the details of this small nugget will therefore appear in the last section. 

Microorganisms may make a substantial contribution to the total phosphatase activity of the rhizosphere, and distinction between the relative importance of enzymes from either source for the utilization of soil organic phosphorus remains to be established. Recent evidence suggests that phosphatases derived from fungal sources show higher efficiency for utilization of model organic phosphorus compounds than those derived from plant roots (Tarafdar et al.,... 

Although aquatic biochemical ecologists have focused nearly exclusively on lytic processes for dissolved organic phosphorus utilization, heterotrophic bacteria can directly take up certain organic phosphorus compounds from their surrounding environment without prior hydrolysis (Table 9.2). E. coli is known to have two different processes by which glycerol 3-phosphate can be taken up without prior hydrolysis... 

Siuda, W. and Chrost, R.J. (2001) Utilization of selected dissolved organic phosphorus compounds by bacteria in lake water under nonlimiting orthophosphate conditions. Polish Journal of Environmental Studies 1 0, 475 83. 

It is well-known that multiple bonds involving heavier main group elements are unstable, and thus, some stabilizing techniques are needed to prepare compounds with heavy unsaturated skeletons. Kinetic stabilization utilizing steri-cally crowded substituents to stabilize a reactive species is a method to obtain such multiple bonding, and many kinds of kinetically stabilized heavy multiple bonds have been derived so far [Ij. As for phosphorus compounds, in 1978 Bickelhaupt and coworkers reported the first kinetically stabilized phosphorus-carbon double bond I (phosphaethene) [2], and in 1981 Yoshifuji and coworkers reported the first stable phosphorus-phosphorus double bond II (diphosphene)... 

Enrichment cultures have been tried repeatedly in the past to search for bacteria that can utilize reduced phosphorus compounds as electron donors in their dis-similatory metabolism. Both hypophosphite and phosphite could be excellent electron donors for a microbial energy metabolism because their oxidation releases electrons at very low redox potentials (Table 1). So far, only one bacterium has been isolated that can run its energy metabolism on the basis of phosphite oxidation to phosphate. 

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