- Complexation and Chemisorption of Trimethylphosphine on Ni Zeolites
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After room temperature saturation of dehydrated NiY with trimethylphosphine two complexes are formed in the supercages.They are identified and quantified by reflectance spectroscopy as 0.92+ per unit cell and 6-8l)3-Ni-PMe3>2+ per unit cell (Ol is a lattice oxygen).The former is diamagnetic and trigonal bipyramidal, the latter is paramagnetic and compressed tetrahedral. 2+ is only stable in excess PMe3, while the mono-phosphine complex is stable to ca. 383 K in vacuo.On NiX only the paramagnetic compressed tetrahedral complex is formed.The ligand field parameters of this complex were calculated.Chemisorption on lattice and extralattice oxygens gives strongly held O=PMe3, O=P(OMe)3 and a range of decomposition products such as CO, CO2, H2O, hydrocarbons and oxygenated P on the surface.These products were qualitatively identified by i.r. and mass spectrometry.
- Schoonheydt, Robert A.,Wouwe, Dirk Van,Leeman, Hugo
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- Solvent isotope effects as a probe of general catalysis and solvation in phosphoryl transfer
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Phosphoryl transfer to methanol from PNNN, PMNN, and PMMN exhibits general base catalysis by acetate ion but no detectable catalysis by acetic acid. For PNNN, acetate catalysis produces normal solvent isotope effects that arise from a one-proton catalytic bridge in the transition state. The proton inventory for the least reactive substrate PMMN is suggestive of transition-state stabilization, while the proton inventory for the most reactive substrate PNNN suggests only generalized transition-state solvation. Furthermore, the proton inventory for PMNN suggests an intermediate situation. The data are consistent with a model in which transition states with exterior concentrations of charge favor stabilization of the charge by isotope-fractionating one-proton bridges, while transition states with distributed charge favor stabilization of the charge by many distributed sites.
- Bryan,Schowen,Schowen
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- Catalysis of the oxidation of triphenylphosphine and of trimethyl phosphite by hydrogen peroxide in the presence of Fe(III) compounds
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The oxidation of triphenylphosphine to the corresponding oxide in pyridine is faster in the presence of Fe(III) compounds, especially FeCl3. Even greater effects are seen for the oxidation of trimethyl phosphite.
- Barton, Derek H.R.,Hill, David R.,Hu, Bin
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- Preparation and reactivity of half-sandwich dioxygen complexes of ruthenium
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Dioxygen complexes [Ru(η5-C5Me5)(η2-O2){P(OEt)3}2]BPh4 (1) and [Ru(η5-C5Me5)(η2-O2)(PPh3){P(OR)3}]BPh4 (2, 3) [R = Me (2), Et (3)] were prepared by allowing chloro-complexes RuCl(η5-C5Me5)[P(OEt)3]2 and RuCl(η5-C5Me5)(PPh3)[P(OR)3] to react with air (1 atm) in the presence of NaBPh4. Substitution of the η2-O2 in 1-3 by alkenes [CH2CH2, CHCHCO(O)CO] and terminal alkynes (PhCCH) afforded [Ru(η5-C5Me5)(η2-CH2CH2){P(OEt)3}L]BPh4 (4) [L = P(OEt)3 (a), PPh3 (b)], [Ru(η5-C5Me5){η2-CHCHCO(O)CO}{P(OEt)3}2]BPh4 (5) and [Ru(η5-C5Me5){CC(H)Ph}{P(OEt)3}2]BPh4 (6) derivatives. Protonation of dioxygen complexes 1-3 with triflic acid yielded phosphate complexes [Ru(κ1-OTf)(η5-C5Me5){P(O)(OEt)3}2] (7) and [Ru(κ1-OTf)(η5-C5Me5){P(O)Ph3}{P(O)(OMe)3}] (8). A reaction path for the formation of complexes 7 and 8 is proposed by DFT studies. Besides phosphate complex 7, protonation of 1 under a CH2CH2 atmosphere (1 atm) afforded acetic acid. Treatment of complexes 7 and 8 with tBuNC afforded the tris(isocyanide) derivative [Ru(η5-C5Me5)(tBuNC)3]BPh4 (9). The complexes were characterised spectroscopically (IR and NMR) and by X-ray crystal structure determination of 1, 2 and 3.
- Albertin, Gabriele,Antoniutti, Stefano,Bortoluzzi, Marco,Castro, Jesús,Ferraro, Valentina
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- Photooxidation of Trimethyl Phosphite in Nitrogen, Oxygen, and para-Hydrogen Matrixes at Low Temperatures
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(Chemical Equation Presented) Trimethyl phosphite (TMPhite) was photooxidized to trimethyl phosphate (TMP) in N2, O2, and para-H2 matrixes at low temperatures to correlate the conformational landscape of these two molecules. The photooxidation produced the trans (TGG)-rich conformer with respect to the ground state gauche (GGG) conformer of TMP in N2 and O2 matrixes, which has diverged from the conformational composition of freshly deposited pure TMP in the low-temperature matrixes. The enrichment of the trans conformer in preference to the gauche conformer of TMP during photooxidation is due to the TMPhite precursor, which exists exclusively in the trans conformer. Interestingly, whereas the photooxidized TMP molecule suffers site effects possibly due to the local asymmetry in N2 and O2 matrixes, in the para-H2 matrix owing to the quantum crystal nature the site effects were observed to be self-repaired.
- Ramanathan,Sundararajan,Gopi,Sankaran
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- Photoinduced single electron transfer activation of organophosphines: Nucleophilic trapping of phosphine radical cation
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Photophysical studies show that organophosphines (1-4) form charge transfer stabilized exciplex with excited singlet 1DCN*. One electron oxidation of phosphines to corresponding radical cation via phosphine... 1DCN* electron donor, acceptor pair dissociation is reported. Phosphine radical cations are lound to react readily with moisture to give phosphine oxides.
- Pandey, Ganesh,Pooranchand, Dinah,Bhalerao
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- Rates and Mechanisms of Hydrolysis of Esters of Phosphorous Acid
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Trialkyl phosphites hydrolyze in alkali several hudred times as fast as do the corresponding phosphates; in acid, however, the phosphite hydrolyzes 1E12 times asa fast as the phosphate.Dialkyl phosphites (i.e., dialkyl hydrogen phosphonates) hydrolyze in alkali more than 1E5 times as fast as do the corresponding triesters, presumably by way of metaphosphites as intermediates.The mechanisms of these various processes are discussed.The date are of interest in connection with the phosphite syntheses of DNA.
- Westheimer, F. H.,Huang, Shaw,Covitz, Frank
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- Terminal Titanyl Complexes of Tri- and Tetrametaphosphate: Synthesis, Structures, and Reactivity with Hydrogen Peroxide
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The synthesis and characterization of tri- and tetrametaphosphate titanium(IV) oxo and peroxo complexes is described. Addition of 0.5 equiv of [OTi(acac)2]2 to dihydrogen tetrametaphosphate ([P4O12H2]2-) and monohydrogen trimetaphosphate ([P3O9H]2-) provided a bis(μ2,κ2,κ2) tetrametaphosphate titanyl dimer, [OTiP4O12]24- (1; 70% yield), and a trimetaphosphate titanyl acetylacetonate complex, [OTiP3O9(acac)]2- (2; 59% yield). Both 1 and 2 have been structurally characterized, crystallizing in the triclinic P1? and monoclinic P21 space groups, respectively. These complexes contain TiO units with distances of 1.624(7) and 1.644(2) ?, respectively, and represent rare examples of structurally characterized terminal titanyls within an all-oxygen coordination environment. Complexes 1 and 2 react with hydrogen peroxide to produce the corresponding peroxotitanium(IV) metaphosphate complexes [O2TiP4O12]24-(3; 61% yield) and [O2TiP3O9(acac)]2- (4; 65% yield), respectively. Both 3 and 4 have been characterized by single-crystal X-ray diffraction studies, and their solid-state structures are presented. Complex 3 functions as an oxygen atom transfer (OAT) reagent capable of oxidizing phosphorus(III) compounds (P(OMe)3, PPh3) and SMe2 at ambient temperature to result in the corresponding organic oxide with regeneration of dimer 1.
- Stauber, Julia M.,Cummins, Christopher C.
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- Oxidizing O,O,O-trimethyl phosphorothioate with hydrogen peroxide or ozone
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Oxidization of O,O,O-trimethyl phosphorothioate to the corresponding oxo (P=O) compound is accomplished under mild conditions with hydrogen peroxide or ozone. Urea hydroperoxide was found to be a serviceable solid-state source of hydrogen peroxide; it was a better oxidizing agent than 30% hydrogen peroxide and resulted in better yield. It was also proved that ozone was the most effective oxidizer, with formation of purer products in higher yield (90.1%) than with hydrogen peroxide. Springer Science+Business Media B.V. 2011.
- Chen, Xinzhi,Li, Guihua,Qian, Chao
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- METHOD FOR PRODUCING PHOSPHOESTER COMPOUND
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PROBLEM TO BE SOLVED: To provide a method whereby, a phosphate compound selected from the group consisting of orthophosphoric acid, phosphonic acid, phosphinic acid, and anhydrides of them is used as raw material and, by one stage reaction, a corresponding phosphoester compound is produced. SOLUTION: To an aqueous solution of a phosphate compound, added is an organic silane or siloxane compound having an alkoxy group or an aryloxy group, and the mixture is subjected to a heating reaction, thereby producing a corresponding phosphoester compound without requiring a catalyst. SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT
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Paragraph 0023; 0026-0028
(2021/09/27)
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- Method for compounding organphosphorus by using black phosphorus
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The invention discloses a method for compounding organphosphorus by using black phosphorus. The method takes the black phosphorus as a reaction raw material, safely and efficiently compounds organic phosphate, sulpho-phosphite ester, amino phosphite ester, alkylphosphine, alkylphosphine oxide and other organphosphorus with wide usages, a conventional synthsis route by using phosphorus halide and phosphate to compound the organphosphorus is avoided, the synthesis steps are simple and short, the production technology is operated simply and easily, the reproducibility is good, the reaction is simple and green, the use of a phosphorus halide reagent is avoided, the range of the synthetic organphosphorus is wider, the method satisfies the requirements of green chemical development, and the large-scale production can be achieved.
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Paragraph 0054; 0055; 0056; 0060
(2018/10/19)
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- Thermally induced structural transformations of linear coordination polymers based on aluminum tris(diorganophosphates)
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The thermal transitions of inorganic-organic hybrid polymers composed of linear aluminum tris(diorganophosphate) chains with a general formula of catena-Al[O2P(OR)2]3 (where R = C1-C8 alkyl group or phenyl moiety) have been studied by means of DSC, powder XRD, TGA and TG-QMS, as well as optical spectroscopy. DSC and XRD reveal that most of them undergo reversible structural transformations in the solid state between ?100 and 200 °C caused by the changes in conformation of their organic substituents; however, a translational displacement of the rigid polymeric chains occurs only in the case of the derivative bearing long 2-ethylhexyl groups, which becomes liquid at about 140 °C. The thermal decomposition of the studied polymers begins between 200 and 265 °C depending on the type of organic substituent R decorating their aluminophospate core. TGA combined with mass spectrometry of the evolved gaseous products shows that the pyrolytic decomposition of Al[O2P(OR)2]3 proceeds either through β-elimination of olefin (for compounds with C2-C8 aliphatic ligands), or a homolytic cleavage of the P-OR bond (for methyl and phenyl derivatives); both processes are accompanied by condensation of the newly formed POH groups and liberation of water. Powder XRD, FTIR and SEM analyses of the solid residues indicate that thermolysis of Al[O2P(OR)2]3 accompanied by olefin elimination leads to the formation of condensed aluminum phosphates, mainly aluminum cyclohexaphosphate, exhibiting porous morphology. On the other hand, thermal degradation of methyl or phenyl derivatives results in amorphous aluminophosphate residues, and the latter contains conducting carbonaceous phases.
- D?bowski, Maciej,?okaj, Krzysztof,Ostrowski, Andrzej,Zachara, Janusz,Wiecińska, Paulina,Falkowski, Pawe?,Krztoń-Maziopa, Anna,Florjańczyk, Zbigniew
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supporting information
p. 16480 - 16491
(2018/12/05)
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- Preparation of the HIV Attachment Inhibitor BMS-663068. Part 1. Evolution of Enabling Strategies
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The development of two enabling routes that led to the production of >1000 kg of BMS-663068 (3) is described. The route identified for the initial 100 kg delivery to support development activities and initial clinical trials involved the conversion of 2-amino-4-picoline to the parent active pharmaceutical ingredient (API), followed by pro-drug installation and deprotection. To eliminate the problematic isolation of the parent API and synthesis of di-t-butyl(chloromethyl)phosphate, a second-generation pro-drug installation route was developed which involved the conversion of a late-stage common intermediate to an N(1)-thioether derivative followed by chloromethylation, displacement with di-t-butylpotassium phosphate, and deprotection. This second strategy resulted in the multikilogram scale preparation of the API in 14 linear steps and ～7% overall yield.
- Fox, Richard J.,Tripp, Jonathan C.,Schultz, Mitchell J.,Payack, Joseph F.,Fanfair, Dayne D.,Mudryk, Boguslaw M.,Murugesan, Saravanababu,Chen, Chung-Pin H.,La Cruz, Thomas E.,Ivy, Sabrina E.,Broxer, Sévrine,Cullen, Ryan,Erdemir, Deniz,Geng, Peng,Xu, Zhongmin,Fritz, Alan,Doubleday, Wendel W.,Conlon, David A.
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p. 1095 - 1109
(2017/08/23)
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- Metal-free phosphonation of heteroarene N-oxides with trialkyl phosphite at room temperature
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A new protocol is described for the conversion of heteroarene N-oxides to heteroarylphosphonates through in situ activation with bromotrichloromethane. The N-oxides of isoquinoline, quinoline, quinoxaline and 1,10-phenanthroline were fast transformed into the corresponding heteroarylphosphonates in up to 92% yield under mild conditions in the absence of solvent and metal catalysts. The good functional group tolerance, low cost, feasibility of scale up, and wide availability of reagents make this method a prominent complement to the Hirao coupling.
- Chen, Ming-Tao,You, Xia,Bai, Li-Gang,Luo, Qun-Li
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supporting information
p. 3165 - 3169
(2017/04/21)
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- Method of synthesizing alkyl phosphate
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The invention relates to a method of synthesizing alkyl phosphate. The method includes: in the process of synthesizing alkyl phosphate, using inert substance to mix with reactant alcohol; dropwise adding phosphorus oxychloride at low temperature, allowing reaction at normal temperature for a period of time, and rising temperature for reaction; using alkali for neutralizing, washing with water, and distilling to remove low-boiling-point solvent and reactant; depressurizing and distilling to obtain high-purity alkyl phosphate. Due to existence of the third inert substance, reaction is enabled to be milder, and high yield is realized; a lot of generated hydrogen chloride is removed in a gaseous mode, so that alkali consumption is reduced and production cost is lowered.
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Paragraph 0042; 0043
(2017/01/02)
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- Simple and compelling biomimetic metal-organic framework catalyst for the degradation of nerve agent simulants
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Inspired by biology, in which a bimetallic hydroxide-bridged zinc(II)-containing enzyme is utilized to catalytically hydrolyze phosphate ester bonds, the utility of a zirconium(IV)-cluster-containing metal-organic framework as a catalyst for the methanolysis and hydrolysis of phosphate-based nerve agent simulants was examined. The combination of the strong Lewis-acidic ZrIV and bridging hydroxide anions led to ultrafast half-lives for these solvolysis reactions. This is especially remarkable considering that the actual catalyst loading was a mere 0.045 % as a result of the surface-only catalysis observed. Nervous breakdown: UiO-66, a biomimetic metal-organic framework based on a zirconium oxo cluster, is capable of rapidly catalyzing the breakdown of phosphate-based nerve agent simulants. UiO-66 catalyzes both methanolysis and hydrolysis of the nerve agent simulant methyl paraoxon (shown in the graphic, R=CH3) with high catalytic efficiency.
- Katz, Michael J.,Mondloch, Joseph E.,Totten, Ryan K.,Park, Jin K.,Nguyen, Sonbinh T.,Farha, Omar K.,Hupp, Joseph T.
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p. 497 - 501
(2014/01/23)
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- Catalytic solvolytic and hydrolytic degradation of toxic methyl paraoxon with la(catecholate)-functionalized porous organic polymers
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Two robust catechol-functionalized porous organic polymers (catPOPs) with different Td-directing nodes were synthesized using a cobalt-catalyzed acetylene trimerization (CCAT) strategy. Postsynthesis metallation was readily carried out with La(
- Totten, Ryan K.,Weston, Mitchell H.,Park, Jin Kuen,Farha, Omar K.,Hupp, Joseph T.,Nguyen, Sonbinh T.
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p. 1454 - 1459
(2013/07/26)
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- Investigation of non-Rehm-Weller kinetics in the electron transfer from trivalent phosphorus compounds to singlet excited sensitizers
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Singlet excited states (1S* and 1S +*) of neutral and monocationic sensitizers, S and S +, respectively, were quenched by electron transfer (ET) from a variety of trivalent phosphorus compounds (Z3P). The quenching rate constants kq, which are equal to the rate constants kET of the ET from Z3P to 1S* or 1S+*, were determined by the Stern-Volmer method. The logarithm of kET was plotted against free-energy change ΔG0 of the ET. The plot deviated upward from the line predicted by the Rehm-Weller (RW) theory in the endothermic region, the deviation being larger in the ET to a neutral acceptor 1S* than in the ET to a cationic acceptor 1S+*. Such a kinetic behavior is in sharp contrast to that observed in the ET from amines (R 3N), where the ET to either neutral or cationic acceptor takes place according to the RW prediction. The ET from a donor, Z3P or R 3N, to a neutral acceptor 1S* is a charge-separation type, during which electrostatic attraction between the donor and the acceptor is generated, whereas the ET to a cationic acceptor 1S+* is a charge-shift type, which results in neither electrostatic attraction nor repulsion. Difference in kinetics-energetics relationship by the type of ET, which is not recognized in the ET from R3N donor, becomes "visible" when Z 3P is used as a donor. Copyright 2013 John Wiley & Sons, Ltd. The rate constants kET of electron transfer from trivalent phosphorus compounds to singlet photoexcited sensitizers were determined by the Stern-Volmer method. LogkET-ΔG0 plots were found to deviate upward from the line predicted by the Rehm-Weller theory, with deviation being larger in ET to neutral acceptors than in ET to cationic acceptors. Copyright
- Yasui, Shinro,Tsujimoto, Munekazu
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p. 1090 - 1097
(2014/01/06)
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- Tailoring the specificity and reactivity of a mechanism-based inactivator of glucocerebrosidase for potential therapeutic applications
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Chaperoning an enzyme: Fluorosugar glycosidase inactivators with tunable phosphorus-based leaving groups react quickly with the catalytic nucleophile in β glucocerebrosidase (blue circle; Bn=benzyl). In Western blot analysis, Gaucher patient cells treated with these inactivators show increased intracellular levels of mutant enzyme, presumably because of increased transit from the endoplasmic reticulum (pale blue) to the lysosome (pale pink). Copyright
- Rempel, Brian P.,Tropak, Michael B.,Mahuran, Don J.,Withers, Stephen G.
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supporting information; experimental part
p. 10381 - 10383
(2011/12/04)
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- Biomimetic oxidation reactions of a naked manganese(V)-Oxo porphyrin complex
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The intrinsic reactivity of a manganese(V)-oxo porphyrin complex, a typically fleeting intermediate in catalytic oxidation reactions in solution, has been elucidated in a study focused on its gas-phase ion-chemistry. The naked high-valent MnV-oxo porphyrin intermediate 1 ([(tpfpp)Mn VO]+; tpfpp=meso-tetrakis(pentafluorophenyl)porphinato dianion), has been obtained by controlled treatment of [(tpfpp)Mn III]Cl (2-Cl) with iodosylbenzene in methanol, delivered in the gas phase by electrospray ionization and assayed by FT-ICR mass spectrometry. A direct kinetic study of the reaction with selected substrates, each containing a heteroatom X (X=S, N, P) including amines, sulfides, and phosphites, was thus performed. Ionic products arising from electron transfer (ET), hydride transfer (HT), oxygen-atom transfer (OAT), and formal addition (Add) may be observed, with a predominance of two-electron processes, whereas the product of hydrogen-atom transfer (HAT), [(tpfpp)MnIVOH]+, is never detected. A thermochemical threshold for the formation of the product radical cation allows an evaluation of the electron-transfer ability of a Mn V-oxo complex, yielding a lower limit of 7.85 eV for the ionization energy of gaseous [(tpfpp)MnIVO]. Linear free-energy analyses of the reactions of para-substituted N,N-dimethylanilines and thioanisoles indicate that a considerable amount of positive charge is developed on the heteroatom in the oxidation transition state. Substrates endowed with different heteroatoms, but similar ionization energy display a comparable reaction efficiency, consistent with a mechanism initiated by ET. For the first time, the kinetic acidity of putative hydroxo intermediates playing a role in catalytic oxidations, [(tpfpp)FeIVOH]+ and [(tpfpp)Mn IVOH]+, has been investigated with selected reference bases, revealing a comparatively higher basicity for the ferryl, [(tpfpp)Fe IVO], with respect to the manganyl, [(tpfpp)MnIVO], unit. Finally, the neat association reaction of 2 has been studied with various ligands showing that harder ligands are more strongly bound.
- Lanucara, Francesco,Crestoni, Maria Elisa
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experimental part
p. 12092 - 12100
(2011/11/28)
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- Interaction of α,α-difluoroazides with trivalent phosphorus compounds and triphenylantimony
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α,α-Difluoroazides react with triphenylantimony and various compounds of trivalent phosphorus according to the oxidative fluorination scheme. In the case of trivalent phosphorus compound the primary products are phosphazenes, phosphazides or difluorophosphoranes that may undergo further transformations to the corresponding fluorine derivatives of pentavalent phosphorus. Pleiades Publishing, Ltd., 2010.
- Lermontov,Polivanova,Shkavrov
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experimental part
p. 1646 - 1651
(2011/02/18)
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- The role of structural effects on the reactions of alkoxyl radicals with trialkyl and triaryl phosphites. A time-resolved kinetic study
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(Figure presented) A time-resolved kinetic study on the reactions of alkoxyl radicals with trialkyl and triaryl phosphites ((RO)3P: R = Me, Et, i-Pr, t-Bu; (ArO)3P: Ar = C6H5, 2,4-(t-Bu)2C6H3) has been carried out. In the (RO)3P series, the alkoxyl radicals (cumyloxyl (CumO ·) and benzyloxyl (BnO·)) undergo addition to the phosphorus center with formation of intermediate tetraalkoxyphosphoranyl radicals (R′OP·(OR)3: R = Me, Et, i-Pr, t-Bu; R′ = Bn, Cum). The addition rate constants are influenced by steric effects, decreasing on going from R = Me to R = t-Bu and from BnO · to CumO·. Rate constants for β-scission of the phosphoranyl radicals R′OP·(OR) 3 have also been determined, increasing, for a given alkyl group R, in the order R′ = tert-butyl · reacts with triaryl phosphites (ArO) 3P to give phenoxyl radicals, with rate constants that are influenced to a limited extent by substitution of the aromatic rings. The radical scavenging ability of these substrates is briefly discussed.
- Bietti, Massimo,Calcagni, Alessandra,Salamone, Michela
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scheme or table
p. 4514 - 4520
(2010/10/02)
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- Demonstration of prominent Cu(ll)-promoted leaving group stabilization of the cleavage of a homologous set of phosphate Mono-, Di-, and triesters in methanol
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A series of phosphate mono-, di-, and triesters with a common leaving group (LG) (2′-(2-phenoxy)1, 10-phenanthroline) was prepared, and the kinetics of decomposition of their Cu(II) complexes was studied in methanol at 25°C under sspH-controlled conditions. The Cu(II) complexes of 2-[2′-phenanthrolyl]phenyl phosphate (Cu(ll):6), 2-[2′- phenanthrolyl]phenyl methyl phosphate (Cu(II):7), and 2-[2′-phenanthrolyl] phenyl dimethyl phosphate (Cu(II):8) are tightly bound, having dissociation constants Kd -7 M, with the Cu(II) being in contact with the departing phenoxide. The sspH/rate profile for cleavage of Cu(II): 6 has a low sspH plateau (k0 = 6.3 × 10-3 s-1), followed by a bell-shaped maximum (kcatmax= 14.7 ± 0.4 s -1) dependent on two ionizations with sspK a3 and sspKa 21 = 7.8 ± 0.1 and 11.8 ± 0.2. The sspH/rate profile for cleavage of Cu(ll):7 has a broad plateau from sspH 3 to sspH 10 followed by a descending wing at higher sspH with a gradient of -2. The s spH/rate profile for cleavage of Cu(ll):8 is sigmoidal with two plateaus (Zc1 = (2.0 ± 0.2) × 10-5S-1, k 2 = (1.2 ±0.2) × 10-6S-1), connected by an ionization with a sspKa of 6.03. Activation parameters are given for the reactions in the plateau regions: all three species show similar ΔH# terms of 21.4-21.6 kcal/mol, with major differences in the ΔS- terms, which vary from 18 to 2.3 to -7.4 cal/(mol-K) passing from the mono- to di- to triester. Detailed analyses of the kinetics indicate that the reactions involve spontaneous solvent-mediated cleavage of the Cu(ll)-coordinated phosphate dianion [Cu(ll):6b]° and phosphate diester monoanion [Cu(ll):7b]+ and, for the triester, complexes containing Cu(II) and Cu(II): -OCH 3 designated as [Cu(ll):8a]2+ and [Cu(ll):8b]+. Reactions where methoxide is the active nucleophile are not observed. Comparisons of the rates of the decomposition of these species at their sspH maxima in the neutral sspH region with the estimated rates of the background reactions indicate that leaving group assistance provided by the coordinated Cu(II) accelerates the cleavage of the phosphate mono-, di-, and triesters by 1014 to 1015, 1014, and 105. Detailed Hyperquad 2000 analysis of titration data indicates that phenoxide 9- is bound 23 kcal/mol stronger than the phosphate triester 8. It is the realization of part of this energy in the emerging products resulting from P-O(LG) cleavage that provides the driving force for the catalyzed reactions.
- Tony Liu,Neverov, Alexei A.,Maxwell, Christopher I.,Stan Brown
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supporting information; experimental part
p. 3561 - 3573
(2010/05/01)
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- Reduction of dichlorvos and omethoate residues by O2 plasma treatment
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A practical, inexpensive, and green chemical process is greatly needed for degrading pesticides in food and environmental water. In this work, the impact of O2 plasma treatment on reduction of dichlorvos (DDVP) and omethoate in maize was determ
- Bai, Yanhong,Chen, Jierong,Mu, Hui,Zhang, Chunhong,Li, Baoping
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experimental part
p. 6238 - 6245
(2010/07/06)
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- Leaving group assistance in the La3+-catalyzed cleavage of dimethyl (o-methoxycarbonyl)aryl phosphate triesters in methanol
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The catalytic methanolysis of a series of dimethyl aryl phosphate triesters where the aryl groups contain an o-methoxycarbonyl (o-CO2Me) substituent (4a-i) was studied at 25°C in methanol containing La 3+ at various concentrations and sspH. Determination of the second-order rate constant for La3+ 2-catalyzed cleavage of substrate 4a (dimethyl (o-methoxycarbonyl) phenyl phosphate) as a function of sspH was assessed in terms of a speciation diagram that showed that the process was catalyzed by La3+ 2(-OCH3)x dimers, where x = 1-5, that exhibit only a 5-fold difference in activity between all the species. The second-order catalytic rate constants (k2La) for the catalyzed methanolysis of 4a-i at sspH 8.7 fit a Bronsted relationship of log k2La= (-0.82 ± 0.11)sspKalg + (11.61 ± 1.48), where the gradient is shallower than that determined for a series of dimethyl aryl phosphates that do not contain the o-CO2Me substituent, log k2La = (-1.25 ± 0.06)s spKalg + (16.23 ± 0.75). Two main observations are that (1) the o-CO2Me group preferentially accelerates the cleavage of the phosphate triesters with poor leaving groups relative to those with good leaving groups and (2) it provides an increase in cleavage rate relative to those of comparable substrates that do not have that functional group, e.g., k2La(dimethyl o-(methoxycarbonyl) phenyl phosphate)/k2La(dimethyl phenyl phosphate) = 60. Activation parameters for the La3+2-catalyzed methanolysis of 4a and dimethyl 4-nitrophenyl phosphate show respective ΔH? (ΔS?) values of 3.3 kcal/mol (-47 cal/mol·K) and 0.7 kcal/mol (-46.5 cal/mol·K). The data are analyzed in terms of a concerted reaction where the catalytic complex (La3+2( -OCH3)x-1) binds to the three components of a rather loose transition state composed of a nucleophile CH3O -, a nucleofuge -OAr, and a central (RO)2P 2+-O- in a way that provides leaving group assistance to the departing aryloxy group.
- Edwards, David R.,Liu, C. Tony,Garrett, Graham E.,Neverov, Alexei A.,Brown, R. Stan
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supporting information; experimental part
p. 13738 - 13748
(2010/01/06)
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- Mechanism study on the oligomerization of amino acids into peptides by phosphorus trichloride
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As treated by phosphorus trichloride, amino acids could oligomerize into polypeptides. Based on the results obtained by 31P-NMR and ESI-MS/MS, a possible reaction mechanism was proposed. The mechanism might undergo a penta-coordinated phosphorus intermediat. The activated amino acid was a five-membered cyclic penta-coordinated phosphorus intermediate. The nucleophilic attack of the amino group from an amino acid or peptide on the carbonyl group of intermediate led to the formation of peptide and released one equivalent dichloride phosphoric acid. The repetition of the reaction sequence generated a series of oligopeptides. Copyright Taylor & Francis Group, LLC.
- Zhao, Wenjie,Zhao, Dongxin,Lu, Kui
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body text
p. 691 - 698
(2009/05/07)
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- Catalytic hydrophosphorylation of dialkyl 2-allylmalonates
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The reaction of dialkyl hydrogen phosphites and diphenylphosphine oxide with dialkyl 2-allylmalonates in the presence of [Pd(Ph3P) 4] is studied. The addition of the hydrophosphoryl compounds to the multiple bond is established to proceed by the Markovnikov rule. The reaction is accompanied by the side process of malonate dealkoxycarbonylation whose contribution to the main process depends on the nature of the reagents.
- Reznikov,Skvortsov
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p. 1170 - 1176
(2008/02/12)
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- Electrocatalytic eco-efficient functionalization of white phosphorus
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The novel eco-efficient methods to transform white phosphorus into the esters of phosphoric, phosphorous and phosphonic acids, tertiary phosphines and other organophosphorus compounds under conditions of electrochemical catalysis were elaborated. The mechanism of these processes was investigated using the method of cyclic voltammetry and preparative electrolysis.
- Budnikova, Yulia H.,Yakhvarov, Dmitry G.,Sinyashin, Oleg G.
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p. 2416 - 2425
(2007/10/03)
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- Solvent deuterium kinetic isotope effects for the methanolyses of neutral C=O, P=O and P=S esters catalyzed by a triazacyclododecane : Zn 2+-methoxide complex
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The methanolyses of several organophosphate/phosphonate/phosphorothioate esters (O, O-diethyl O-(4-nitrophenyl) phosphate, paraoxon, 3; O, O-diethyl S-(3,5-dichlorophenyl) phosphorothioate, 4; O-ethyl O-(2-nitro-4-chlorophenyl) methylphosphonate, 5; O, O-dimethyl O-(3-methyl-4-nitrophenyl) phosphorothioate, fenitrothion, 6; O-ethyl S-(3,5-dichlorophenyl) methylphosphonothioate 7) and a carboxylate ester (p-nitrophenyl acetate, 2) catalyzed by methoxide and the Zn2+(-OCH3) complex of 1,5,9- triazacyclododecane (1 : Zn2+(-OCH3)) were studied in methanol and d1-methanol at 25°C. In the case of the methoxide reactions inverse skie's were observed for the series with values ranging from 2 to 1.1, except for 7 where the kD/kH = 0.90 ± 0.02. The inverse kD/kH values are consistent with a direct nucleophilic methoxide attack involving desolvation of the nucleophile with varying extents of resolvation of the TS. With the 1 : Zn 2+(-OCH3) complex all the skie values are kD/kH = 1.0 ± 0.1 except for 7 where the value is 0.79 ± 0.06. Arguments are presented that the fractionation factors associated with complex 1 : Zn2+(-OCH3) are indistinguishable from unity. The skie's for all the complex-catalyzed methanolyses are interpreted as being consistent with an intramolecular nucleophilic attack of the Zn2+-coordinated methoxide within a pre-equilibrium metal : substrate complex. The Royal Society of Chemistry 2005.
- Maxwell, Chris,Neverov, Alexei A.,Brown, R. Stan
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p. 4329 - 4336
(2007/10/03)
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- Rate and product studies with dimethyl phosphorochloridate and phosphorochloridothionate under solvolytic conditions
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The specific rates of solvolysis of dimethyl phosphorochloridate and of dimethyl phosphorochloridothionate are very well correlated using the extended Grunwald-Winstein equation, with incorporation of the NT solvent nucleophilicity scale and the YCl, solvent ionizing power scale. The sensitivity parameters (l and m) are similar to each other and also similar to previously recorded values for solvolyses of arenesulfonyl chlorides, which were proposed to follow a concerted displacement mechanism. For solvolyses in aqueous ethanol or aqueous methanol the product selectivities (S) are close to unity. For solvolyses in aqueous 2,2,2-trifluoroethanol, the values are too small to accurately measure, showing a very large preference for product formation involving nucleophilic attack by the water component. It is concluded that the chloride and chloridothionate solvolyses, in common with the solvolyses of arenesulfonyl chlorides, follow a concerted displacement mechanism.
- Kevill, Dennis N.,Carver, Jeffrey S.
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p. 2040 - 2043
(2007/10/03)
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- Trimethyl phosphite as a trap for alkoxy radicals formed from the ring opening of oxiranylcarbinyl radicals. Conversion to alkenes. Mechanistic applications to the study of C-C versus C-O ring cleavage
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Trimethyl phosphite, (MeO)3P, is introduced as an efficient and selective trap in oxiranylcarbinyl radical (2) systems, formed from haloepoxides 8-13 under thermal AIBN/n-Bu3SnH conditions at about 80 °C. Initially, the transformations of 8-13, in the absence of phosphite, to allyl alcohol 7 and/or vinyl ether 5 were measured quantitatively (Table 1). Structural variations in the intermediate oxiranylcarbinyl (2), allyloxy (3), and vinyloxycarbinyl (4) radicals involve influences of the thermodynamics and kinetics of the C-O (2 → 3, k1) and C-C (2 → 4, k2) radical scission processes and readily account for the changes in the amounts of product vinyl ether (5) and allyl alcohol (7) formed. Added (MeO)3P is inert to vinyloxycarbinyl radical 4 and selectively and rapidly traps allyloxy radical 3, diverting it to trimethyl phosphate and allyl radical 6. Allyl radicals (6) dimerize or are trapped by n-Bu3SnH to give alkenes, formed from haloepoxides 8, 9, and 13 in 69-95% yields. Intermediate vinyloxycarbinyl radicals (4), in the presence or absence of (MeO)3P, are trapped by n-Bu3SnH to give vinyl ethers (5). The concentrations of (MeO)3P and n-Bu3SnH were varied independently, and the amounts of phosphate, vinyl ether (5), and/or alkene from haloepoxides 10, 11, and 13 were carefully monitored. The results reflect readily understood influences of changes in the structures of radicals 2-4, particularly as they influence the C-O (k1) and C-C (k2) cleavages of intermediate oxiranylcarbinyl radical 2 and their reverse (k-1, k-2). Diversion by (MeO)3P of allyloxy radicals (3) from haloepoxides 11 and 12 fulfills a prior prediction that under conditions closer to kinetic control, products of C-O scission, not just those of C-C scission, may result. Thus, for oxiranylcarbinyl radicals from haloepoxides 11, 12, and 13, C-O scission (k1, 2 → 3) competes readily with C-C cleavage (k2, 2 → 4), even though C-C scission is favored thermodynamically.
- Ding, Bangwei,Bentrude, Wesley G.
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p. 3248 - 3259
(2007/10/03)
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- Reactions of trialkyl phosphites with mono- and diacylals of halo-substituted acetic acids
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Trialkyl phosphites react with diacylals of di- and trichloroacetic acids by the pathway of the Perkow reaction; with monoacylals of bromo- and iodoacetic acids, by the pathway of the classical Arbuzov reaction; and with monoacylals of di- and trichloroacetic acids, by the pathway of the nonclassical Arbuzov reaction.
- Gazizov,Gaisin,Khairullin,Safina,Karimova,Petrova
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p. 1738 - 1741
(2007/10/03)
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- Irreversibility of single electron transfer occurring from trivalent phosphorus compounds to iron(III) complexes in the presence of ethanol
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Various types of trivalent phosphorus compounds (1; Ph(3-n)P(OR)n) underwent single electron transfer (SET) to unsubstituted (2H) and 5-chloro-substituted tris(1, 10-phenanthroline)iron(III) complexes (2Cl) in the presence of ethanol in acetonitrile, resulting in the reduction of 2 to the corresponding iron(II) complexes. The rate constants (kp) for the overall SET process were determined spectrophotometrically to show that within each series of 1 with an identical alkoxy group OR, log kp correlates linearly with the difference in the half-wave potentials (ΔE1/2) between 1 and 2. The slope of each correlation line gave an α-value for each series of 1. The α-values were significantly smaller than unity, indicating that the SET step is irreversible, even though this step is endothermic. The trivalent phosphorus radical cation 1.+ generated in the SET step undergoes a rapid ionic reaction with ethanol, which is certainly the origin of the irreversibility. Upon examining the α-values more closely, it was found that the transition state of the SET step becomes earlier with increasing bulkiness of the substituent OR. It is concluded that 1 and 2 form a tight encounter complex to undergo SET from the former to the latter.
- Yasui, Shinro,Itoh, Kenji,Tsujimoto, Munekazu,Ohno, Atsuyoshi
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p. 1311 - 1318
(2007/10/03)
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- Microwave catalyzed reactions of H-dimethylphosphonate with oxiranes
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Microwave catalyzed reactions of H-dimethylphosphonate with 1,2-epoxydecane, 5,6-epoxy-1-hexene, 1,2-epoxybutane and cyclohexene oxide have been found to cause oxirane ring opening, deoxygenation and hydrophosphorylation. 1,2-Epoxydecane gave three pairs
- Munavalli,Rohrbaugh,Berg,Longo,Durst
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p. 215 - 230
(2007/10/03)
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- Oxidizing alkoxylation of phosphine in alcoholic solutions of iodine
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Oxidizing alkoxylation of PH3 to trialkyl phosphates was performed in pyridine-alcoholic solutions of iodine. The optimal conditions of the reaction were found.
- Polimbetova,Borangazieva
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p. 2079 - 2082
(2007/10/03)
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- Method and apparatus for improving the uniformity of distribution of a phosphorus-containing agent throughout a maleic anhydride catalytic reactor
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Improved methods and apparatus for the preparation of maleic anhydride by reacting a hydrocarbon having at least four carbon atoms in a straight chain with molecular oxygen in a catalytic reactor, the reactor comprising a fixed catalyst bed having active sites comprising a vanadium-phosphorus-oxygen catalyst for the catalytic oxidation of the hydrocarbon to maleic anhydride, said process further comprising the continuous or intermittent introduction of a phosphorus-containing agent to the reactor. The introduction of the phosphorus-containing agent into the maleic anhydride production system is controlled so to provide for a more uniform distribution of the phosphorus-containing agent throughout the reactor. The methods of the invention are effective to reduce deposits of the phosphorus-containing agent or decomposition products of the phosphorus-containing agent on reactor surfaces other than the catalytic bed thereby decreasing reactor maintenance and increasing reactor lifetime.
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- Diisocyanates containing hydantoin groups and polyurethanes in which they are present
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Diisocyanates of the formula (I) where R1is a C1-C10-hydrocarbon radical and R3is a C1-Cl2-hydrocarbon group and n is an integer from 1 to 10, are described.
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- Fluorinated phosphorus compounds: Part 3. the synthesis of symmetrical and unsymmetrical fluoroalkyl phosphates
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Treatment of phosphorus pentachloride with four molar equivalents of fluoroalcohol gave symmetrical phosphates (RFO)3P=O in isolated yields between 10-92% [RF=CF3CH2, C2F5CH2, HCF2CF2CH2, C3F7CH2, (FCH2)2CH, (CF3)2CH, C2F5(CH3)CH]. The reaction proceeded best for fluoroalcohols having many fluorine atoms. 2,2-Difluoroethanol HCF2CH2OH and 1,3-difluoroisopropanol (FCH2)2CHOH did not react cleanly and gave product mixtures. Hexafluoroisopropanol produced a 3:7 mixture of symmetrical phosphate [(CF3)2CHO]3P=O and chlorophosphorane [(CF3)2CHO]4PCl. The latter reacted readily with water and alcohols. Heating the chloridates CF3CH2OP(O)Cl2, (CF3CH2O)2P(O)Cl and (C2F5CH2O)2P(O)Cl with various fluoroalcohols in the presence of calcium chloride catalyst gave unsymmetrical phosphates in isolated yields between 46-83%. The mixed phosphate (CF3CH2O)2P(O)OCH2C 2F5 did not react with butanol or propylamine in dichloromethane at room temperature.
- Timperley, Christopher M.,Holden, Ian,Morton, Ian J.,Waters, Matthew J.
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p. 153 - 161
(2007/10/03)
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- Quenching of a photosensitized dye through single-electron transfer from trivalent phosphorus compounds
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Various types of trivalent phosphorus compounds 1 undergo single-electron transfer (SET) to the photoexcited state of rhodamine 6G (Rho+(*)) in aqueous acetonitrile to quench the fluorescence from Rho+(*). The rate constants k(p) for the overall SET process were determined by the Stern-Volmer method. The rate is nearly constant at a diffusion-controlled limit in the region of E( 1/2 )(1) +), whereas log k(p) depends linearly on E( 1/2 )(1) in the region of E( 1/2 )(1) > 1.3 V, the slope of the correlation line being -αF/RT with α = 0.2. The potential at which the change in dependence of log k(p) on E( 1/2 )(1) occurs (1.3 V) is in accordance with the value of E( 1/2 )(Rho+(*)) (1.22 V) that has been obtained experimentally. Thus, the SET step is exothermic when E( 1/2 )(1) 1.3 V. The α-value (0.2) obtained in the endothermic region shows that the SET step from 1 to Rho+(*)is irreversible in this region. Trivalent phosphorus radical cation 1(·+) generated in the SET step undergoes an ionic reaction with water in the solvent rapidly enough to make the SET step irreversible. In contrast, the SET from amines 2 and alkoxybenzenes 3 to Rho+(*) is reversible when the SET step is endothermic, meaning that the radical cations 2(·+) and 3(·+) generated in the SET step undergo rapid 'back SET' in the ground state to regenerate 2 and 3.
- Yasui, Shinro,Tsujimoto, Munekazu,Itoh, Kenji,Ohno, Atsuyoshi
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p. 4715 - 4720
(2007/10/03)
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- Oxidation in organophosphorus chemistry: Potassium peroxymonosulphate
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Potassium peroxymonosulphate (Oxone) is used as an efficient, chemoselective and stereoselective oxidizing agent for a wide variety of phosphorous, phosphothio- and phosphoseleno-compounds.
- Wozniak, Lucyna A.,Stec, Wojciech J.
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p. 2637 - 2640
(2007/10/03)
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- Absolute viscosity and density of trisubstituted phosphoric esters
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This paper presents measurements on the absolute viscosity (η) and density (ρ) of trisubstituted phosphoric esters which are useful in understanding their flow mechanism necessary for accessing their role as plasticizers. The effect of chain length and branching has been examined on the η and ρ trends. From η data, by using the Vogel-Tammann-Fulchur (VTF) equation, the VTF temperature (To) has been obtained which also represents the ideal glass transition temperature. To is related to the flexibility of the molecules. It is observed that To initially decreases with molecular weight, reaches a minimum, and increases thereafter. The initial decrease in To has been attributed to the enhanced flexibility of the phosphate esters. Reversal of flexibility with relative molar mass beyond 400 is due to the gentle collision of the arms of the trisubstituted phosphoric esters. This has been further corroborated from the molar mass exponent as exhibited in the η-molar mass plot. The isomeric effect on η has also been investigated in tricresyl phosphates, hitherto for the first time. The ortho isomer has highest η among the isomers. The para isomer was found to have lowest To and hence highest flexibility compared to the ortho and meta isomers.
- Kannan,Kishore
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p. 649 - 655
(2007/10/03)
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- 11,12-cyclic phosphite or phosphate derivatives of erythromycin and related macrolides
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Disclosed are the antibacterial compounds having the formulas: STR1 or pharmaceutically acceptable salts and esters thereof. Also disclosed are the processes for preparing compounds of formulas (I), and II) of the invention, pharmaceutical compositions comprising a therapeutically effective amount of a compound of the invention in combination with a pharmaceutically acceptable carrier, as well as a method for treating bacterial infections by administering to a mammal a pharmaceutical composition containing a therapeutically-effective amount of a compound of the invention.
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- Synthesis of Trialkyl Phosphates from White Phosphorus
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A new method was proposed for preparing trialkyl phosphates directly from white phosphorus by its electrolysis in a mixture of acetonitrile, alcohol, and water with tetraethylammonium iodide as supporting electrolyte. To increase the amount of the product synthesized in the unit volume of the electrolyte solution and the productivity of the process, phosphorus and water are added to the electrolyte in portions, which allows synthesis of up to 1 mol of trialkyl phosphate in 1 1 of the electrolyte solution.
- Romakhin,Nikitin
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p. 1023 - 1026
(2007/10/03)
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- Reaction of trivalent phosphorus compounds with an Fe(III) complex in the presence of alcohol. Single electron transfer accompanied by a P-O bond formation
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Reactions of various types of trivalent phosphorus compounds with iron(III) complex in the presence of ethanol have been examined kinetically, showing that the single electron transfer from the former compounds to the latter is followed by rapid reaction of the resulting trivalent phosphorus radical cations with ethanol.
- Yasui, Shinro,Itoh, Kenji,Tsujimoto, Munekazu,Ohno, Atsuyoshi
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p. 1019 - 1020
(2007/10/03)
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- Kinetics of Reaction of Diphenylphosphinic Dihydrazide with Electrophilic Reagents in the Presence of Organic Bases
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Kinetics of the reactions of diphenylphosphinic dihydrazide with mesityl isothiocyanate, phenyl isothiocyanate, and picryl chloride in the presence of nitrogen-, oxyden-, and sulfur-containing organic bases in benzene at 25°C are studied. Accelerating effect of nitrogen- and oxygen-containing bases in the reactions of diphenylphosphinic hydrazide with all the studied electrophilic reagents correlates with the ability of these catalysts to form hydrogen bonds (pKHB). Sulfur-containing compounds practically do not exhibit catalytic properties in the studied systems. With increasing substrate reactivity, the catalytic effect of organic catalysts decreases.
- Yanchuk
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p. 220 - 223
(2007/10/03)
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- Dichotomy in the reactivity of trivalent phosphorus compounds Z3P (Z = Ph, nBu, OR) observed in the photoreaction with a ruthenium complex
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Solutions of tris(2,2′-bipyridyl)ruthenium(II) dichloride (Ru2+) and various types of trivalent phosphorus compounds Z3P (Z = Ph, nBu, OR; 1) in methanol have been photolyzed with visible light at 20 °C under an argon atmosphere, resulting in the oxidation of I to the corresponding pentavalent oxo compounds Z3P=O and ligand exchange of Ru2+ with 1. The former process takes place via single-electron transfer (SET) from 1 to Ru2+ in the photoexcited state, Ru2+*, which gene-rates the radical cation intermediate Z3P*+ from 1. The latter results from nucleophilic attack of 1 upon Ru2+*. The results show that 1 can act either as an electron donor or as a nucleo-phile toward Ru2+*. The rate constants for both processes are estimated. An excellent linear correlation is found between the logarithm of the SET rate and the oxidation potential for both the aromatic and aliphatic trivalent phosphorus compounds examined here; the slope of the plot is much less negative than expected on the basis of Rehm-Weller theory. Such behavior in the SET rates is interpreted by comparison with SET quenching by amines. On the other hand, a dualparameter correlation analysis shows that the ligand exchange is regulated by both steric and electronic factors in 1. WILEY-VCH Verlag GmbH, 1997.
- Yasui, Shinro,Tsujimoto, Munekazu,Shioji, Kosei,Ohno, Atsuyoshi
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p. 1699 - 1707
(2007/10/03)
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- Oxidative P-O and P-C Coupling of Butanol with Phosphine in the Presence of Oxidizers and Platinum(IV) and Platinum(II)
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A butanol solution of Na2PtCl6 at 60-80°C in the presence of p-benzoquinone or NaBrO3 is found to rapidly consume even traces of PH3 until complete reduction of benzoquinone to hydroquinone or NaBrO3 to NaBr, respectively. The nature of products depends on the valence state of platinum and the nature of the oxidizer. Without an oxidizer, platinum(IV) is reduced to platinum(II) with formation of tributyl phosphate, the product of P-O coupling of PH3 with BuOH, while platinum(II) is reduced to platinum(0) with formation of butylbis(α-hydroxybutyl)phosphine oxide Bu(α-PrCHOH)2PO, the product of P-C coupling of PH3 with BuOH. In the presence of benzoquinone, which oxidizes Pt(0) to Pt(II), a P-C bond is formed, while in the presence of sodium bromate, which regenerates Pt(II) to Pt(IV), P-O coupling of PH3 with BuOH occurs. The products and principal steps of this new reaction were studied by the methods kinetics, red-ox potentiometry, chemical modeling, inhibition of free-radical reactions, 31P NMR, IR and X-ray photoelectron spectroscopy, X-ray spectral microanalysis, and gas-liquid chromatography. We showed that the P-C coupling of PH3 with BuOH is promoted by platinum(II) complex, while P-O coupling is promoted by platinum(IV) complex. In the key steps the Pt(II) butoxyphosphide complex PtCl3(OBu)(PH2)- arises from reaction of the Pt(II) phosphide complex with platinum(IV). The red-ox decomposition of intermediate complexes leads to formation of phosphinite (BuO)2PH2 and Pt(II), or (α-hydroxybutyl)phosphine and Pt(0). The catalytic cycles are completed by fast steps of oxidative butoxylation of (BuO)PH2 to (BuO)3PO or by α-hydroxybutylation of (PrCHOH)PH2 to Bu(PrCHOH)2PO, and oxidation of Pt(II) to Pt(IV) with bromate or Pt(0) to Pt(II) with benzoquinone, respectively.
- Dorfman,Polimbetova,Aibasov
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p. 231 - 247
(2007/10/03)
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- Synthesis of dialkyl phosphites and trialkyl phosphates by oxidation of sodium hypophosphite by copper(II) chloride
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Sodium hypophosphite oxidazies in alcoholic solution of CuCl2 at 50-80 deg C to give dialkyl phosphite and trialkyl phosphate.The yield of trialkyl phosphate increases with decreasing molecular weight of the alcohol and reaches ca. 100percent for MeOH and EtOH.The optimal conditions were found, and the mechanism of oxidation of NaPH2O2 to (RO)2PHO and (RO)3PO by copper(II) chloride was studied.The reaction proceeds via the formation of alkyl hypophosphite and copper(II) complexes with alkyl hypophosphite and dialkyl phosphite, which undergo inner-sphere two-electron redox decomposition with the liberation of dialkyl phosphite and trialkyl phosphate, respectively.
- Dorfman, Ya. A.,Aleshkova. M. M.
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p. 515 - 520
(2007/10/03)
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- Electrosynthesis of aliphatic esters of phosphorus acids from white phosphorus in alcohol solutions, involving radical cations of phenothiazine and triarylamine
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Aliphatic esters of phosphorus acids can be prepared from white phosphorus by electrolysis of emulsified white phosphorus in alcohol solutions of phenothiazine or triarylamine.
- Budnikova, Yu. G.,Kargin, Yu. M.
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p. 504 - 507
(2007/10/03)
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- Reaction of a cation radical generated from trivalent phosphorus compound through single-electron transfer to arenediazonium salt
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A cation radical generated from a trivalent phosphorus compound through single-electron transfer to an arenediazonium salt undergoes both ionic and radical reactions. Relative ease of these reactions depends mainly on the number of phenyl ligands on the phosphorus atom.
- Yasui, Shinro,Shioji, Kosei,Ohno, Atsuyoshi
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p. 2695 - 2698
(2007/10/02)
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- OXIDATIVE ALKOXYLATION OF TETRAPHOSPHORUS
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A new quick and selective reaction of the oxidative alkoxylation of tetraphosphorus to trialkyl phosphates in the presence of CuCl2 is examined.Quantitative data are given on the effect of all the components and products of the reaction on the yield of trialkyl phosphates and on the key stages of the process: the reduction of CuCl2 by tetraphosphorus and the oxidation of CuCl by oxygen.The mechanism of the reaction is discussed.
- Dorfman, Ya. A.,Abdreimova, R. R.
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p. 206 - 214
(2007/10/02)
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