Phosphorous compounds example

Phosphor compounds have problems when atoms are 3 A apart, producing incorrect geometries. P4O6 for example is predicted to have P-P bonds differing by 0.4 A, although experimentally they are identical. 

Small amounts of phosphonium complexone [1560] are sufficient to increase adhesion to the stratal rock. Table 18-4 illustrates an example for plugging solution with Portland cement and phosphonium complexone. Calcium chloride acts as a regulator of the setting time in the suggested composition. More precisely, phosphonium complexone stands for certain chelating phosphorous compounds (e.g., oxyethylidene diphosphonic acid, nitrilo-trimethyl phosphonic acid, sodium tripolyphosphate, or amiphol) [1540]. The mixture is applicable at low temperatures from 20° to 75° C. 

As a typical example from industrial practice we consider the simulation of a process with the reaction of methylphosphinic acid and butanol to methylphosphinic acid butyl ester and water, which was modeled by Gordana Hofmann-Jovic at InfraServ Knapsack [C28]. Because of the lack of experimental data for the binary systems with phosphorous compounds, COSMO-RS was used for the prediction of the binary activity coefficients. Then the results were fitted by an NRTL equation and the entire process was modeled by a commercial process simulator. The resulting phase diagrams were in close agreement with experimental measurements obtained later (Fig. 8.2). 

When in the structural vicinity of a fluorine substituent, phosphorous chemical shifts can be significantly affected by the presence of fluorine substituents but not in the way one might think. In contrast to the intuitive expectation based upon the inductive effect of fluorine, which results in the deshielding of protons and carbons in their vicinity, the effect of proximal fluorine upon the chemical shifts of phosphorous compounds is to shield the phosphorous nuclei. Scheme 2.10 provides a few examples. 

Phosphonic acid esters are derived from phosphonic acid (often erroneously called phosphorous acid), which is shown with some of its esters in Figure 18.3 Only two of the H atoms of phosphonic acid are ionizable, and hydrocarbon groups may be substituted for these atoms to give phosphonic acid esters. It is also possible to have esters in which a hydrocarbon moiety is substituted for the H atom that is bonded directly to the phosphorus atom. An example of such a compound is dimethylmethylphosphonate, shown in Figure 18.3. This type of compound has the same elemental formula as triesters of the hypothetical acid P(OH)3, phosphorous acid. Examples of triesters of phosphorous acid, such as trimethylphosphite, are shown in Figure 18.3. 

Several phosphorous compounds having a P=S bond are also catalysts for this reaction. For example, heating of phenyl isocyanate with triphenylphosphine sulfide at 160 °C affords diphenylcarbodiimide. Since triphenylphosphine sulfide was recovered unchanged, a different mechanism seems to be operative. A tricyclic P S compound, S=P[N(Me)CH2CH2l3N, also catalyzes the transformation of isocyanates to carbodiimides. Triphenylarsine oxide and triphenylantimony oxide also catalyze the conversion of isocyanates into carbodiimides. The catalytic activity of the oxides of phosphorous, arsenic and antimony are in agreement with the dipole moments of... 

Environment, toxicity With durable flame retardancy, formaldehyde emission during curing and after finishing, phosphorous compounds in the waste water Antimony oxide and organic halogen donators (DBDPO and HCBC) are discussed as problems (for example possibility of generating polyhalo-genated dioxins and furanes)... 

Some other examples of attack of 1- chloroethyl ethyl carbonate with soft nucleophile phosphorous compounds are gathered in scheme 79 (Ref. 104). 

Scheme 79 Examples of reactions of 1-chloroethyl ethyl carbonate with phosphorous compounds.

The next example shows how the complexity of an RDF descriptor might influence the classification. The compiled data set consisted of benzene derivatives, phosphorous compounds, and amines. The Cartesian RDF descriptors were calculated once including all atoms and a second time without hydrogen atoms. The left-hand image in Figure 6.11 shows the classification with normal RDF descriptors. Two remarkable situations occur ... 

Boron-nitrogen and boron-phosphorous compounds are classical textbook examples of donor-acceptor complexes. The chemical bonds of the Lewis-acid Lewis-base complexes are usually explained in terms of frontier orbital interactions and/or quasiclassical electrostatic attraction in the framework of the Hard and Soft Acid and Base (HSAB) model [73]. We were interested in seeing if the differences between the bond strengths of boron-nitrogen and boron-phosphorous complexes for different boranes, amines and phosphanes can be explained with the EDA method. 

All commercially used phosphorous compounds are derived from phosphate rocks. Some deposits accumulated have billions of tons of phosphate, for example the Phos-poria deposit of the western USA and Morocco. Large deposits are also found in Australia, China, Florida, and the Kola Peninsula. The deposits of Christmas Island are of guano origin and are rapidly being depleted by over-use, though other reserves of phosphate ore should last for a thousand years. Globally, over 75 million tons of such rocks, containing about 15 million tons of P, are mined annually. About 95% of this output is destined directly for the food chain, with 90% as fertilizers and 4% in the form of different additives to livestock fodder (3.4%) or human foodstuffs (0.7%). About 4.5% of mined phosphorus is used... 

Other solid-state NMR studies of silica-surface reactions have included studies with aqueous AIC3 [42], and with AICI3 vapor, gaseous phosphorous compounds (e.g., PCI3, POCI3) and ammonia vapor (vide infra). Of course, in such cases there are additional NMR nuclides from which potentially useful data can be obtained, for example, Al and P. An example is given in Figure 34.36, which shows Al MAS NMR spectra reported by Sato and Maciel [5v] of catalyst material... 

Typical processing stabilizers for polypropylene and butylated hydroxy-toluene (BHT) as the primary antioxidant and phosphates and phosphonates as secondary antioxidants. Examples of the latter that are commonly used are tetrakis-(2,4-di-terr-butyl-phenyl)-4-4 -bisphenylylenediphosphonite, distearyl-pentaerythrityl-diphosphonite, tris-(nonylphenyl)-phosphite, tris-(2,4-di-teft-butyl-phenyl)-phosphite and bis(2,4-di-ferr-butyl-phenyl)- pentaerythrityl-diphosphite. In commercial polypropylenes, phosphorous compounds are always used together with a sterically hindered phenol. The compounds are commonly added in concentrations between 0.05 and 0.25%. 

Table 1 shows some examples of our basic research and new businesses. Toray commercialized nylon 6 fiber In 1950. The raw material, -caploractam, was produced by a conventional multi step proress at that time, but it has been today completely replaced by my invention. The business of carbon fiber and advanced composite materials was the outcome of basic research on oi anic synthesis using phosphorous compounds in our Basic Research Laboratories. Investigation in holography provided a researcher with the idea to use a holograph as a memoi, and the world-first Kanji-Printer was introduced in 1974, even though the memory was later replaced by a semiconductor. Our pharmaceutical business was initiated from basic research on interferon and biotechnologies. In 1985 we... 

As listed in Table 3.24, organic phosphorous compounds such as tris(2,4-di-ieri-butyl-phenyl)phosphite [165] and tris(tribromoneopentyl) phosphate [166] have been attempted. A new class of iV-alkoxy hindered amines (NOR HAS) have been pursued by Ciba as fire retardants [167]. An example of these compounds is Flamstab NOR TM 116, the structure of which is shown below. It is a reaction product of A,A -ethane -l,2-diyl6z5(l,3-propanediamine),... 

Georg Wittig, a German chemist, was awarded the 1979 Nobel Prize in Chemistry for his work with phosphorous compounds and his discovery of a reaction with enormous synthetic utility. Below is an example of this reaction, called the Wittig reaction (pronounced Vittig) ... 

Since only the characteristic light wavelengths generated by HP or 81= are permitted to enter the PMT, the detection signal is considered to be an indication that the sample contains sulfur and/or phosphorous compounds. Such direct sampling results do not permit precise substance identification. As discussed previously, detection indicates only that the sample consists of substances that contain sulfur and/or phosphorus, which may or may not be targeted toxic chemicals. The AP2C is an example of this principle of detection. 

In the past, many variations of the sol-gel process have been developed and used to produce powders with different Ca/P ratios, by altering not only the quantity and composition of precursors but also the processing variables. As the synthesis of HA requires a calcium to phosphorus molar ratio of 1.67 1 in the final product, a number of caldum/phosphorus precursor combinations have been used in the preparation of HA powders. For example, calcium nitrate or different calcium alkoxides and 2-ethyl-hexyl phosphate, triethyl phosphate or orthophos-phoric acid, have been used as the calcium and phosphoras precursors, respectively. The major limitation for appUcation of the sol-gel process was shown to be the very poor solubility of the calcium alkoxides in organic solvents, and the poor reactivity of the phosphorous compounds. The effective control of stoichiometry due to the volatility of the phosphorous compounds used also represented a challenge. 

Acid rhodamines are made by the iatroduction of the sulfonic acid group to the aminoxanthene base. The preferred route is the reaction fluorescein (2) with phosphorous pentachloride to give 3,6-dichlorofluoran (fluorescein dichloride) (23), which is then condensed with a primary aromatic amine in the presence of 2inc chloride and quicklime. This product is then sulfonated. For example, if compound (23) (fluorescein dichloride) is condensed with aniline and the product is sulfonated. Acid Violet 30 Cl45186) (24) is produced. 

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