Phosphorus m Compounds

From Azides and Phosphorus(m) Compounds.—The reactions of aminophosphines, and of phosphites, with trimethylsilyl azide are not as simple as might be expected, in view of the formation of significant quantities of by-products, (11) and (12), which have been identified.21... 

Formally the extrusion of sulfur from episulfides by a thiophilic reagent (phosphorus(m) compounds, organometallic compounds) introduces unsaturation, but the formation of the thiiran and the sulfur extrusion are usually coupled [209-211]. 

Bonds to Fluorine.—Phosphorus (m) Compounds. SCF wavefunctions for PF allow estimation of the dissociation enthalpy (4.7 eV), the dipole moment (0.6 D), and the P—F distance (1.58 A), etc.,261 while the emission spectra of the species produced by the action of microwave discharges on HPF2 and PF3 may be analysed in terms of the PF diatomic.262 Experimental data for the e.s.r. parameters of the PF2 radical263 and those calculated by ab initio methods264 are in good agreement. 

Bonds to Nitrogen.—Phosphorus (m) Compounds. From ab initio M.O. calculations on H2NPH2 the barrier to pyramidal inversion at phosphorus can be shown to be higher than that in phosphine.353 This is compatible with... 

An alternative route to the interesting two-co-ordinate phosphorus(m) compound (47) has been devised and follows equation (10).3,9a Contrary to the earlier report, the product appears to be stable at room temperature in daylight for long periods. On reaction with Me3SiN3, compound (47) gives... 

From Azides and Phosphoras(in) Compounds.— Although phosphorus(m) compounds and azides generally undergo a ready reaction, two examples (4) and (5) of the class of azidophosphines have recently been prepared. The bulky di-isopropylamino-groups in (4) confer thermal stability such that the compound can be distilled at reduced pressure." Compound (5) was identified spectroscopically at low temperatures,... 

Interesting products have also been obtained from the reactions of phenyl azide with the birdcage -type phosphorus(m) compounds P4(NMe)g and PgOg. The former substrate gave P4(NMe)6 (=NPh) [ = 1 or 4, e.g. structure (6)], and products with n = 2 or 3 were identified by P n.m.r. The... 

The three-fold co-ordination of phosphorus(v) in compound (47) has been confirmed by a full X-ray structure important parameters are included with the formula, but noteworthy is the shortness of the P—N(imine) bond, in agreement with the presence of (p-p)ir interaction. Compound (47) is known to be the oxidation product of the phosphorus(m) compound (44) with trimethyl-silylazide, but when diazomethane is used the ylide analogue (Me3Si)2-NP(=NSiMe3)(=CH2) cannot be isolated, and the product is the phosphiran (48) formed by a 1,2-cycloaddition.A similar process occurs between diazomethane and (47), when the novel azaphospiridine (49) results. 

From Azides and Phosphorus(m) Compounds.—The reactions of azides with phosphorus(iii) compounds continue to be an important general route to monophosphazenes ... 

Phosphorus. Reactions of three-co-ordinate phosphorus(m) compounds generally involve associative mechanisms, as in exchange at (Me2As)2P(CF3), in the reaction of phosphines with hydroxide, and of trialkyl phosphites with hypochlorite. In the last case, the phosphorus appears to be five-co-ordinate in the transition state. The reaction sequence for trialkyl phosphites plus phosphorus trifluoride includes a Michaelis-Arbuzov rearrangement. The first stereochemical study of reactions of phosphorus(iii) compounds with radicals demonstrates retention of configuration this result is consistent with more than one possible mode of reaction. Further examples of reactions of phosphorus(iii) compounds appear later, when analogous derivatives of phosphorus(m) and phos-phorus(v) are compared. 

This reaction has now been extended to other phosphorus(m) compounds... 

A comprehensive review of the preparation, reactions, and n.m.r. spectra of phosphorus-fluorine compounds has appeared. This year s literature has been notable for the first detailed applications of ab initio SCF-MO calculations to the problems of bonding in halogenophosphines and their derivatives. - Comparison of the results of such theoretical calculations with experimental data obtained from photoelectron spectra shows a good correlation in the case of phosphorus trichloride and phosphoryl chloride, and of phosphorus trifluoride and its borane complex. ... 

Regitz, M., and Maas, G. Short-Lived Phosphorus (V) Compounds Having Coordination Number 3, 97,71-119(1981). 

The configurations at phosphorus in compounds 73-76 were assigned on the basis of II-NMR data assuming that in phosphorus-containing heterocycles, the protons in a 1,3-m-relation to a P=0 group are deshielded. Thus, since H4 and H5 resonate at lower field in compounds 73a-76a than in compounds 73b-76b, the P=0 group must be cis to H4 and H5 in the a series [32]. These assignments were fully supported by the crystal structure studies of 75a, which showed that this... 

Malekin, S.I., V.I. Yakutin, M.A. Sokal skii, Yu.L. Kruglyak, and I.V. Martynov. "Mechanism of the Reaction of a-Chloronitrosoalkanes with Phosphorus (III) Compounds." Zhurnal Obshchei Khimii 42 (1972) 807-811 (In Russian). 

A. Seidel, M. Wagner, J. Endtner, W. Ebenbeck, T. Eckel, and D. Wittmann, Flame-resistant polycarbonate compositions containing phosphorus-silicon compounds, US Patent 7144 935, assigned to Bayer Aktiengesellschaft (Leverkusen, DE), December 5, 2006. 

Nucleic acids - [NUCLEIC ACIDS] (Vol 17) -in cell culture products [CELL CULTURE TECHNOLOGY] (Vol 5) -coordination compounds as probes [COORDINATION COMPOUNDS] (Vol 7) -electrophoresis of [ELECTROSEPARATIONS - ELECTROPHORESIS] (Vol 9) -phosphorus m [MINERALNUTRIENTS] (Vol 16) -role m sterilization [DISINFECTANTS AND ANTISEPTICS] (Vol 8) -ruthenium cmpds as probes [PLATINUM-GROUP METALS, COMPOUNDS] (Vol 19)... 

Se NMR spectra of selenadiphospholes and diselenaphospholes 44, 45, 78, and 47 were reported (Table 25) <2002CEJ2705>. In compounds 44, 45, 78, and 47, the exocyclic selenium atom is at lower frequency relative to those within the heterocycle. A l/(Se,Se) coupling of 271 Hz is characteristic of compound 45. In molecule 47, the ring atom Se-3 has a 2/(P,Se) coupling to the phosphorus(v) center P-1 of 20 Hz. On the other hand, there is no resolved coupling between the exocyclic Se-1 and the internal phosphorus(m) center P-2. 

Beugelmans, R. and Chbani, M. (1995) SRN1 — synthesis of nitrogen, sulfur and phosphorus heterocyclic compounds... 

R. M. Smillie and G. Krotokov (1960). Phosphorus-containing compounds in Euglena gracilis grown under difefrent conditions. Arch. Biochem. Biophys., 89, 83-89. 

The phosphoms azides P(N3)3, P(N3)4+, P(N3)5, and P(N3)6 have long been known (see Phosphorus-Nitrogen Compounds). More recently, the binary arsenic, antimony, and bismuth M(N3)3, the cations As(N3)4+ and Sb(N3)4+, and the arsenic and antimony M(N3)4 and M(N3)e anions have been synthesized. While the cations and binary azides are very sensitive(the bismuth compound has not been isolated), the anions, in combination with sufficiently large cations such as As(Ph)4+, are less sensitive. Attempts to prepare the As(V) and Sb(V) pentaazides resulted in explosions. 

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