- Photochemical Radical C–H Halogenation of Benzyl N-Methyliminodiacetyl (MIDA) Boronates: Synthesis of α-Functionalized Alkyl Boronates
-
α-Haloboronates are useful organic synthons that can be converted to a diverse array of α-substituted alkyl borons. Methods to α-haloboronates are limiting and often suffer from harsh reaction conditions. Reported herein is a photochemical radical C-H halogenation of benzyl N-methyliminodiacetyl (MIDA) boronates. Fluorination, chlorination, and bromination reactions were effective by using this protocol. Upon reaction with different nucleophiles, the C?Br bond in the brominated product could be readily transformed to a series of C?C, C?O, C?N, C?S, C?P, and C?I bonds, some of which are difficult to forge with α-halo sp2-B boronate esters. An activation effect of B(MIDA) moiety was found.
- Yang, Ling,Tan, Dong-Hang,Fan, Wen-Xin,Liu, Xu-Ge,Wu, Jia-Qiang,Huang, Zhi-Shu,Li, Qingjiang,Wang, Honggen
-
supporting information
p. 3454 - 3458
(2020/12/17)
-
- Ene-Yne Metathesis of Allylphosphonates and Allylphosphates: Synthesis of Phosphorus-Containing 1,3-Dienes
-
A variety of ene-yne cross metathesis reactions were performed using unsaturated phosphonate and phosphate reagents, affording the corresponding phosphorylated 1,3-diene products in good to excellent yields. These difficult ene-yne metatheses employed a Grubbs catalyst bearing a cyclic amino alkyl carbene ligand. A variety of terminal alkynes of varying substitution underwent the reaction, and different phosphorus-containing alkenes were found to give the conjugated diene products in high yields. The resulting dienes were further transformed by Horner-type Wittig reactions and a Diels-Alder cycloaddition.
- Rohde, Laurence N.,Wild, Thérèse H.,Diver, Steven T.
-
p. 1371 - 1384
(2021/02/05)
-
- Preparation method of phosphate ester compound
-
The invention discloses a preparation method of a phosphate ester compound, belonging to the field of phosphate ester compounds. The preparation method of the phosphate ester compound comprises the following steps: putting sodium diethyl phosphate into a reactor as a raw material, then putting a catalyst, a reaction solvent and an alkylating reagent into the reactor, conducting stirring, heating and reacting for a period of time, and finally, carrying out post-treatment on reaction liquid to obtain triethyl phosphate. According to the method, sodium diethyl phosphate is taken as the raw material, so the waste is treated by the waste, resources are recycled, and pollution is reduced; chloroethane is taken as the alkylating reagent; and thus, a novel, efficient, environment-friendly and economical method for synthesizing a triethyl phosphate compound is provided.
- -
-
Paragraph 0042-0055
(2021/08/25)
-
- METHOD FOR PRODUCING PHOSPHOESTER COMPOUND
-
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
- -
-
Paragraph 0023-0028
(2021/09/27)
-
- Some Transformations of Mono-and Dichloro(diethoxyphosphoryl)acetaldehydes
-
Addition of ethanol and diethyl phosphonate to the carbonyl group of 2,2-dichloro-2-(diethoxyphosphoryl)-acetaldehyde has been studied, and the corresponding α-chloro ether, acetal, and phosphorylated metrifonate have been obtained. α,α-Dichloro-α-phospho
- Allakhverdieva, G. E.,Ismailov, V. M.,Mamedov, I. A.,Sadykhova, N. D.,Yusubov, N. N.
-
-
- LiI/TBHP Mediated Oxidative Cross-Coupling of P(O)–H Compounds with Phenols and Various Nucleophiles: Direct Access to the Synthesis of Organophosphates
-
An efficient and mild method for the direct phosphorylation of phenols, alcohols, and amines with P(O)–H has been reported by LiI/TBHP mediated oxidative cross-coupling reaction. Moreover, this protocol extended to β-keto esters for the synthesis of enol phosphates using H-phosphonates. Notably, this developed method applied for the synthesis of organopesticides such as paraoxon, cyanophos, and methyl parathion. The key features of this protocol are mild conditions, short reaction time, good functional group tolerance, and broad substrate scope.
- Anitha, Thippani,Ashalu, Kashamalla Chinna,Sandeep, Mummadi,Mohd, Aabid,Wencel-Delord, Joanna,Colobert, Francoise,Reddy, Kallu Rajender
-
p. 7463 - 7474
(2019/12/03)
-
- Cross-linked poly(4-vinylpyridine-N-oxide) as a polymer-supported oxygen atom transfer reagent
-
Oxygen atom transfer (OAT) reagents are common in biological and industrial oxidation reactions. While many heterogeneous catalysts have been utilized in OAT reactions, heterogeneous OAT reagents have not been explored. Here, cross-linked poly(4-vinylpyridine-N-oxide), called x-PVP-N-oxide, was tested as a heterogeneous OAT reagent and its oxidation chemistry compared to its molecular counterpart, pyridine-N-oxide. The insoluble oxidant x-PVP-N-oxide demonstrated comparable reactivity to pyridine-N-oxide in direct oxidation reactions of phosphines and phosphites in acetonitrile, but x-PVP-N-oxide did not react in other solvents. The polymer backbone of x-PVP-N-oxide, however, allowed for easy filtering and recycling in sequential oxidation reactions. In addition, x-PVP-N-oxide was tested as the stoichiometric oxidant in a copper-catalyzed OAT reaction to α-diazo-benzeneacetic acid methyl ester. The heterogeneous oxidant was much less reactive than pyridine-N-oxide, indicating that interaction with the metal catalyst was challenging. These results demonstrated a proof-of-concept that recyclable, polymer-supported OAT reagents could be a viable OAT reagents in direct oxidation reactions without metal catalysts.
- Bauer, Anna M.,Ramey, Erin E.,Oberle, Kjersti G.,Fata, Gretchen A.,Hutchison, Chloe D.,Turlington, Christopher R.
-
supporting information
(2019/10/02)
-
- Method for compounding organphosphorus by using black phosphorus
-
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.
- -
-
Paragraph 0045; 0046; 0047; 0050; 0053
(2018/10/19)
-
- Preparation and reactivity of half-sandwich dioxygen complexes of ruthenium
-
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
-
p. 9173 - 9184
(2018/07/25)
-
- Visible light-mediated oxidative C(sp3)-H phosphonylation for α-aminophosphonates under oxidant-free conditions
-
An external oxidant-free synthesis of α-aminophosphonates by synergistically combining photocatalysis and proton-reduction catalysis is developed herein. The gram-scale experiment demonstrates the potential utility of this protocol. This study may have im
- Niu, Linbin,Wang, Shengchun,Liu, Jiamei,Yi, Hong,Liang, Xing-An,Liu, Tianyi,Lei, Aiwen
-
supporting information
p. 1659 - 1662
(2018/02/14)
-
- Reinvestigation of the iodine-mediated phosphoramidation reaction of amines and P(OR)3 and its synthetic applications
-
A systematic study on the iodine-mediated phosphoramidation reaction of amines and trialkyl phosphites was conducted, which not only disclosed the factors affecting the reaction but also revealed that it could proceed smoothly in CH2Cl2 at room temperature in open air. Using this method, various phosphoramidates with different aliphatic amines and aromatic amines were synthesized in good to excellent yields. Our present investigation shows that this underused method is actually a mild, practical and general way to synthesize phosphoramidates and will have wide applications.
- Chen, Xunwei,Xiao, Zecai,Chu, Hanyu,Wang, Bo,Peng, Ai-Yun
-
p. 6783 - 6790
(2018/09/29)
-
- K2CO3-promoted aerobic oxidative cross-coupling of trialkyl phosphites with thiophenols
-
Convenient, practical and economical phosphorylation of thiols has been achieved via halogen- and metal-free K2CO3-promoted aerobic oxidative cross-coupling of trialkyl phosphites, dimethyl phenylphosphonite, or methyl diphenylphosphinite with thiophenols using air as the oxidant at room temperature. This transformation provides a straightforward route to the construction of phosphorus-sulfur bonds with wide functional group compatibility, which affords phosphorothioates in up to 94% yield.
- Wen, Chunxiao,Chen, Qian,Huang, Yulin,Wang, Xiaofeng,Yan, Xinxing,Zeng, Jiekun,Huo, Yanping,Zhang, Kun
-
p. 45416 - 45419
(2017/10/06)
-
- Eco-Friendly and Industrially Scalable Synthesis of the Sex Pheromone of Lobesia botrana. Important Progress for the Eco-Protection of Vineyard
-
A one-pot synthesis of the pheromone of Lobesia botrana is described. The procedure allows an efficient and economical access to this product which is used for the protection of vineyards.
- Cahiez, Gérard,Guerret, Olivier,Moyeux, Alban,Dufour, Samuel,Lefevre, Nicolas
-
supporting information
p. 1542 - 1546
(2017/10/25)
-
- Hydrophosphonylation of Alkynes with Trialkyl Phosphites Catalyzed by Nickel
-
The use of simple and inexpensive NiCl2?6 H2O as a catalyst precursor for C?P bond formation in the presence of commercially available trialkyl phosphites (P(OR)3, R=Et, iPr, Bu, SiMe3) along with several alkynes is presented. Control experiments showed the in situ formation of (RO)2P(O)H as the species that undergo the addition into the C≡C bond at the alkynes to yield the product of P?H addition. The hydrophosphonylation of diphenylacetylene with P(OEt)3, P(OiPr)3, and P(OSiMe3)3 proceeds in high yields (>92 %) without the need of a specific solvent or ligand. This method is useful for the preparation of organophosphonates for both phenylacetylene as a terminal alkyne model and internal alkynes in yields that range from good to modest.
- Islas, Rosa E.,García, Juventino J.
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p. 4125 - 4131
(2017/10/09)
-
- Method of synthesizing alkyl phosphate
-
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.
- -
-
Paragraph 0044; 0045
(2017/01/02)
-
- An optimized and scalable synthesis of propylphosphonic anhydride for general use
-
Abstract Propylphosphonic anhydride (T3P) is an effective coupling and dehydrating agent, which has been used for a large number of chemical transformations. An efficient and versatile synthetic method is described to synthesize propylphosphonic anhydride (T3P) in pure form, in an overall yield of 51% in four steps from commercially available diethyl phosphonate.
- Pizova, Hana,Bobal, Pavel
-
p. 2014 - 2017
(2015/03/30)
-
- Direct conversion of phosphonates to phosphine oxides: An improved synthetic route to phosphines including the first synthesis of methyl JohnPhos
-
The synthesis of tertiary phosphine oxides from phosphonates was achieved reliably and in good to excellent yields using stoichiometric amounts of alkyl or aryl Grignard reagents and sodium trifluoromethanesulfonate (NaOTf). In the absence of the NaOTf additive, covalent coordination oligomers of magnesium and phosphorus species dominate the reaction, producing very low yields of phosphine oxide, but high conversions of the phosphonate starting material. Mechanistic studies revealed that a five-coordinate phosphorus species - not a phosphinate - is the reaction intermediate. A diverse array of phosphonates was converted to phosphine oxides using a variety of Grignard reagents for direct carbon-phosphorus functionalization. This new methodology especially simplifies the synthesis of dimethylphosphino (RPMe2)-type phosphines by using air-, water-, and silica-stable intermediates. To highlight this reaction, a new Buchwald-type ligand ([1,1′-biphenyl]-2-yldimethylphosphine, or methyl JohnPhos) and a classic bidentate phosphine, bis(diphenylphosphino)propane (dppp), were synthesized in excellent yields.
- Kendall, Alexander J.,Salazar, Chase A.,Martino, Patrick F.,Tyler, David R.
-
supporting information
p. 6171 - 6178
(2015/02/19)
-
- Cross-hetero-dehydrogenative coupling reaction of phosphites: A catalytic metal-free phosphorylation of amines and alcohols
-
Phosphorylation of amines, alcohols, and sulfoximines are accomplished using molecular iodine as a catalyst and H2O2 as the sole oxidant under mild reaction conditions. This method provides an easy route for synthesizing a variety of phosphoramidates, phosphorus triesters and sulfoximine-derived phosphoramidates which are of biological importance.
- Dhineshkumar, Jayaraman,Prabhu, Kandikere Ramaiah
-
supporting information
p. 6062 - 6065
(2014/01/06)
-
- Investigation of non-Rehm-Weller kinetics in the electron transfer from trivalent phosphorus compounds to singlet excited sensitizers
-
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
-
p. 1090 - 1097
(2014/01/06)
-
- A novel approach to isoindolo[2,1-a]indol-6-ones
-
A convenient route to isoindolo[2,1-a]indol-6-ones has been developed starting from the appropriate 2-(N-phthaloyl)benzoic acids. Formation of the acid chlorides with thionyl chloride followed by heating with triethyl phosphite in a suitable solvent resulted in a multistep reaction giving tetracyclic β-ketophosphonates that on reduction with sodium borohydride gave the required indolones in good overall yields. Analogous β-ketophosphonates were also prepared starting with N,N-(1,8-naphthaloyl)-2-aminobenzoic acid and 2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)benzoic acids although of these only the naphthaloyl product could be reduced with sodium borohydride without cleaving the amide bond in the ring system.
- Duncanson, Philip,Cheong, Yuen-Ki,Motevalli, Majid,Griffiths, D. Vaughan
-
experimental part
p. 4266 - 4279
(2012/07/13)
-
- A new route to α-alkyl-α-fluoromethylenebisphosphonates
-
A new route to α-alkyl-α-fluoromethylenebisphosphonates, 2 has been developed starting from commercially available tetraethyl fluoromethylenebisphosphonate (1), and alkyl halides using either caesium carbonate in DMF or sodium dimsyl. De-esterification of 2 provided biologically important α-alkyl-α-fluoromethylenebisphosphonic acid, 3, while alkoxide-induced carbon-phosphorus bond cleavage of 2 gave α- fluorophosphonates, 4, which are useful synthons in organic synthesis.
- Beier, Petr,Opekar, Stanislav,Zibinsky, Mikhail,Bychinskaya, Inessa,Prakash, G. K. Surya
-
supporting information; experimental part
p. 4035 - 4038
(2011/06/28)
-
- Synthetic and mechanistic aspects of halo-F-methylphosphonates
-
The synthesis of a variety of new halo-F-methylphosphonates has been achieved by a Michaelis-Arbuzov type reaction between a halo-F-methane and a trialkyl phosphite. This synthesis has proved to be of wide scope and utility for the high yield preparation of a number of heretofore unknown compounds. The 1H, 19F, 13C and 31P NMR spectroscopic properties are reported in detail. The mechanism for the formation of bromodifluoromethylphosphonates has been shown to proceed through the intermediacy of difluorocarbene:CF2. The phosphonate products have been shown to react with a wide variety of reagents. Fluoride and alkoxide ions react by attack at phosphorus with cleavage of the carbon-phosphorus bond and formation of [:CF2] from the bromodifluoromethylphosphonates and the CFBr2- anion from the dibromofluoromethylphosphonates. Iodide ion and tertiary phosphines react by attack at the ester carbon to give stable phosphonate salts. Hydrolysis of the phosphonate esters with 50% aqueous HCl gives the expected phosphonic acids. Trimethylsilyl bromide attacks phosphoryl oxygen to afford the bis(trimethylsilyl) esters.
- Flynn, Richard M.,Burton, Donald J.
-
experimental part
p. 815 - 828
(2011/10/08)
-
- Protonation and alkylation of organophosphorus compounds with trifluoromethanesulfonic acid derivatives
-
Protonation (alkylation) of triphenylphosphine, triethylphosphite, triphenylphosphine oxide, triethylphosphate, hexamethylphosporamide, and dimethylphosphite with trifluoromethanesulfonic acid, its bisimide, and methyl ester was studied and the corresponding 1H, 13C, 19F, 31P NMR spectra were analyzed.
- Tolstikova,Bel'Skikh,Shainyan
-
scheme or table
p. 474 - 480
(2011/06/23)
-
- The role of structural effects on the reactions of alkoxyl radicals with trialkyl and triaryl phosphites. A time-resolved kinetic study
-
(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
-
scheme or table
p. 4514 - 4520
(2010/10/02)
-
- Hydrogen bonding between solutes in solvents octan-1-ol and water
-
The 1:1 equilibrium constants, K, for the association of hydrogen bond bases and hydrogen bond acids have been determined by using octan-1-ol solvent at 298 K for 30 acid-base combinations. The values of K are much smaller than those found for aprotic, rather nonpolar solvents. It is shown that the log K values can satisfactorily be correlated against αH 2?βH2, where αH 2 and βH2 are the 1:1 hydrogen bond acidities and basicities of solutes. The slope of the plot, 2.938, is much smaller than those for log K values in the nonpolar organic solvents previously studied. An analysis of literature data on 1:1 hydrogen bonding in water yields a negative slope for a plot of log K against αH 2?βH2, thus showing how the use of very strong hydrogen bond acids and bases does not lead to larger values of log K for 1:1 hydrogen bonding in water. It is suggested that for simple 1:1 association between monofunctional solutes in water, log K cannot be larger than about -0.1 log units. Descriptors have been obtained for the complex between 2,2,2-trifluoroethanol and propanone, and used to analyze solvent effects on the two reactants, the complex, and the complexation constant.
- Abraham, Michael H.,Gola, Joelle M. R.,Cometto-Muniz, J. Enrique,Acree, William E.
-
experimental part
p. 7651 - 7658
(2011/02/25)
-
- Synthesis of dichloromethylphosphonates
-
Efficient synthesis of O,O-dialkyl, O-alkyl-N,N-dialkylamido and N,N,N',N'-tetraalkyldiamido dichloromethylphosphonates via treatment of O,O-dialkyl, O-alkyl-N,N-dialkylamido, and N,N,N',N'-tetraalkyldiamido trichloromethylphosphonates with diethyl phosph
- Majewski, Piotr,Koszuk, Jacek F.
-
experimental part
p. 956 - 962
(2009/12/03)
-
- Alkali metal ion catalysis and inhibition in nucleophilic displacement reactions at phosphorus centers: Ethyl and methyl paraoxon and ethyl and methyl parathion
-
(Chemical Equation Presented) We report on the ethanolysis of the P=O and P=S compounds ethyl and methyl paraoxon (1a and 1b) and ethyl and methyl parathion (2a and 2b). Plots of spectrophotometrically measured rate constants, kobsd versus [MOEt], the alkali ethoxide concentration, show distinct upward and downward curvatures, pointing to the importance of ion-pairing phenomena and a differential reactivity of free ions and ion pairs. Three types of reactivity and selectivity patterns have been discerned: (1) For the P=O compounds 1a and 1b, LiOEt > NaOEt > KOEt > EtO-; (2) for the P=S compound 2a, KOEt > EtO- > NaOEt > LiOEt; (3) for P=S, 2b, 18C6-crown-complexed KOEt > KOEt = EtO- > NaOEt > LiOEt. These selectivity patterns are characteristic of both catalysis and inhibition by alkali-metal cations depending on the nature of the electrophilic center, P=O vs P=S, and the metal cation. Ground-state (GS) vs transition-state (TS) stabilization energies shed light on the catalytic and inhibitory tendencies. The unprecedented catalytic behavior of crowned-K+ for the reaction of 2b is noteworthy. Modeling reveals an extreme steric interaction for the reaction of 2a with crowned-K+, which is responsible for the absence of catalysis in this system. Overall, P=O exhibits greater reactivity than P=S, increasing from 50- to 60-fold with free EtO- and up to 2000-fold with LiOEt, reflecting an intrinsic P=O vs P=S reactivity difference (thio effect). The origin of reactivity and selectivity differences in these systems is discussed on the basis of competing electrostatic effects and solvational requirements as function of anionic electric field strength and cation size (Eisenman's theory).
- Um, Ik-Hwan,Shin, Young-Hee,Lee, Seung-Eun,Yang, Kiyull,Buncel, Erwin
-
p. 923 - 930
(2008/09/18)
-
- Efficient aerobic oxidation of phosphines, phosphites, and sulfides by using trialkylborane
-
Treatment of phosphines, phosphites, or sulfides with trialkylborane under air afforded the corresponding oxides in good yields.
- Motoshima, Kosuke,Sato, Akinori,Yorimitsu, Hideki,Oshima, Koichiro
-
experimental part
p. 2229 - 2231
(2009/08/08)
-
- Electrocatalytic eco-efficient functionalization of white phosphorus
-
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.
-
p. 2416 - 2425
(2007/10/03)
-
- Method for the preparation of aryl ethers
-
The invention comprises an enantioselective method of preparing a compound of formula (IV): wherein n, m, R and R1 are as defined herein. Use of the compounds of formula (IV) in a method of preparing compounds of formula (IX) and novel intermediates useful in the method are also described.
- -
-
Page/Page column 9
(2008/06/13)
-
- Rapid and high yield oxidation of phosphine, phosphite and phosphinite compounds to phosphine oxides, phosphates and phosphinates using hypofluorous acid-acetonitrile complex
-
The hypofluorous acid acetonitrile complex was used as a mild, rapid, and effective agent to oxidize a wide variety of phosphines, phosphites and phosphinites to the corresponding phosphine oxide, phosphate and phosphinate compounds.
- Peng, Weimin,Shreeve, Jean'Ne M.
-
p. 1054 - 1056
(2007/10/03)
-
- PROCESS FOR PRODUCING CYCLIC COMPOUND
-
The present invention provides a method for preparing a β-lactam compound of the following Formula (3), which comprises the step of reacting a compound of the following Formula (1) with a trialkyl phosphite represented by the formula (R5O)3P (wherein R5 represents an ethyl group, etc.) in an amount of 2 to 5 moles per mole of the compound and the step of heating the resulting reaction mixture in a diluent, wherein said method is characterized by having the step of completely removing unreacted trialkyl phosphite from the reaction mixture prior to the step of heating. (wherein X represents S, etc., Y represents N, etc., n represents 0 or 1, R1 represents an optionally substituted alkyl group containing 1 to 10 carbon atoms, etc., R2 and R3 each represent an optionally substituted alkyl or heterocyclic group, etc., and R4 represents an alkenyloxy group containing 1 to 6 carbon atoms, etc., provided that R1 and R2 may together form a β-lactam ring, etc.)
- -
-
-
- Synthesis of mixed alkylphosphites and alkylphosphates
-
Some mixed phosphites having two different alkyl chain were obtained as forerunners for mixed phosphates Mixed dialkyl phosphates were obtained in good yields (40-80%) by phase transfer catalysis in liquid-liquid sistem, starting from different dialkyl phosphites and aliphatic alcohols. The reaction conditions were optimized in order to obtain good yields in phosphites and phosphates respectively. Compounds were analyzed by IR, P31-NMR.
- Ilia, Gheorghe,Popa, Adriana,Iliescu, Smaranda,Bora, Alina,Dehelean, Gheorghe,Pascariu, Aurelia
-
p. 1513 - 1519
(2007/10/03)
-
- Electrochemical synthesis of phosphorus esters from white phosphorus in the presence of copper complexes and ethanol
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In the presence of white phosphorus the redox potentials of the copper ions change and the potential of the reduction wave of CuI/Cu 0 shifts noticeably toward more positive values. The Cu I-P4 complex is characterized by a lower value of the electrochemical gap, that is, higher polarizability and reactivity compared to those of the free CuI cation. Phosphorus esters can be synthesized from P4 and ethanol. The latter is in the composition of the copper(II) complexes, which act as a catalyst-charge mediator.
- Budnikom,Kafiyatullina,Sinyashin,Abdreimova
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p. 929 - 938
(2007/10/03)
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- FLUORINATED PHOSPHONIC ACIDS
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Fluorinated phosphonic acid compounds, useful as treatments for substrate surfaces, have the formula (I) : wherein: R?1? is a straight chain alkylene group having from 3 to 21 carbon atoms, an oxa-substituted straight chain alkylene group having from 2 to 20 carbon atoms, or a thia-substituted straight chain alkylene group having from 2 to 20 carbon atoms; R?2? is a perfluoroalkyl group having from 4 to 10 carbon atoms; R?3? is hydrogen, an alkali metal cation, or an alkyl group having from 1 to 6 carbon atoms; and M is hydrogen or an alkali metal cation, with the proviso that if R?1? is an unsubstituted straight chain alkylene group, then the sum of carbon atoms in R?1? and R?2? combined is at least 10.
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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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- Significant and differential acceleration of dephosphorylation of the insecticides, paraoxon and parathion, caused by alkali metal ethoxides.
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In the reaction of paraoxon with alkali metal ethoxides, ion-paired EtO-M+ species are more reactive than the dissociated EtO- with the reactivity order EtO-Li+ EtO-Na+ > EtO-K+ > EtO-, while in the reaction of parathion, the reactivity follows the order
- Um, Ik-Hwan,Jeon, Sang-Eun,Baek, Mi-Hwa,Park, Hye-Ran
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p. 3016 - 3017
(2007/10/03)
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- The reactions of dialkyl phosphites and phosphine oxides with iodosylbenzene
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The reaction of iodosylbenzene with > P(O)H type of acids (dialkyl phosphites, secondary phosphine oxides) was studied. The acids of >P(O)H type add to iodosylbenzene to yield intermediate 6 which in the aprotic solvents yields oxidation products, it means >P(O)OH acids and/or anhydride of >P(O)OP(O) P(O)OR ester is the major product.
- Makowiec, Slawomir,Rachon, Janusz
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p. 941 - 955
(2007/10/03)
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- Oxidative alkoxylation of zinc phosphide in alcoholic solutions of copper(II) chloride
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Oxidative alkoxylation of Zn3P2 with the formation of valuable phosphoric and phosphorous acid esters occurred at a high rate and with a high selectivity in alcoholic solutions of CuCl2 under the action of oxygen at 30-60°C. Depending on the nature of the alcohol, two products were formed, namely, trialkyl phosphates (RO)3PO and dialkyl phosphites (RO)2HPO. Water favored the formation of dialkyl phosphates (RO)2(HO)PO. The kinetics and mechanism of the new catalytic reaction were studied, and the optimal conditions for conducting this reaction were found. The reaction proceeded in a topochemical mode by a separate redox mechanism.
- Dorfman,Ibraimova,Polimbetova
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- Cu-catalyzed oxidative phosphorylation of alkanols with white phosphorus and H2O2
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Oxidative phosphorylation of alkanols with white phosphorus in the presence of catalytic amounts of CuCl2 has been effected. The reaction proceeds in the aqueous H2O2-HCl system exothermically to form dialkylphosphites and trialkylphosphates in a total yield of up to 35%. Conditions for selective synthesis of dialkylphosphites in moderate yield have been found.
- Trofimov, Boris,Timokhin, Boris,Gusarova, Nina,Kazantseva, Marina,Golubin, Alexander
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p. 2385 - 2390
(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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- Iodosobenzene and iodoxybenzene as reagents for oxygen transfer in organophosphorus chemistry
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The application of iodosobenzene (1) and iodoxybenzene (2) for the oxidation reaction of phosphorous, phosphorothiono and phosphoroseleno compounds into the corresponding ≡P(O) analogs is demonstrated. Retention of configuration at the phosphorus atom and full stereoselectivity of these reactions in model diastereoisomeric cis- and trans-2-phenylamino-2-thiono-4-methyl-1.3.2-dioxaphosphorinans (30) as well cis- and trans-2-phenylamino-2-seleno-4-methyl-1.3.2-dioxaphosphorinans (31) systems, are demonstrated.
- Mielniczak,Lopusiński
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p. 505 - 508
(2007/10/03)
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- Kinetic study on denomination of vic-dibromides with trivalent phosphorus compounds
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Various types of trivalent phosphorus compounds (I) brought about reductive debromination of vic-dibromides (2) to afford olefins. The reaction was accelerated by either electron-releasing substituents on the phosphorus of 1 or electron-with-drawing substituants on the α-carbon of 2. The substituent effects, along with the stereochemistry of the reaction, are consistent with an E1CB-like mechanism for the elimination of the two bromine atoms. That is, 1 initially undergoes nucleophilic attack upon a bromine of 2. At the transition state, a fractional positive charge is developed on the phosphorus of 1 and a fractional negative charge on the carbon of 2. This mechanism suggests the importance of an electronic character of the vic-dibromide in determining the relative ease of bromophilicity, carbophilicity, and basicity of the phosphorus of a trivalent phosphorus compound in a reaction with the dibromide. α 2001 John Wiley & Sons, Inc.
- Yasui, Shinro
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p. 217 - 222
(2007/10/03)
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- Hetero trinuclear oxo-bridged complexes of ruthenium porphyrin and iron phthalocyanine
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New diamagnetic hetero bi- and trinuclear oxo-bridged metal complexes of formula (L)(Pc)Fe-O-Ru(TPP′)(O) and (L)(Pc)Fe-O-Ru(TPP′)-O-Fe(Pc)(L) have been prepared from Ru(TPP′)(O)2 and Fe(Pc)(L)2 (TPP′ = tetrakis(4-methoxyphenyl)porphyrinate, Pc = phthalocyanate ion, L = monodentate ligand). The trinuclear complex binds a variety of ligands (4,4′-bipy, 4-MePy, P(OEt)3, pip, NH3, 1-MeIm, P(Me)2Ph) trans to the oxo-bridge. 1H NMR spectra are characterized by large ring current shifts (rcs) due to the TPP′ and Pc ions. The complexes show an unusually weak Pc Q band in their visible spectra at 700 nm and two CT bands in the near-IR region from 1000 to 1500 nm, which are sensitive to the trans ligand. The trinuclear complex can be reversibly oxidized to the +1 and +2 ions, formally Fe(IV)-O-Ru(IV)-O-Fe(III) and Fe(IV)-O-Ru(IV)-O-Fe(IV) at 0.4 and 0.76 V. The +1 ion is chemically obtained by reaction of the neutral species with (Cp)2Fe+ for L = 4-MePy and this reaction is reversed upon addition of L′ = P(Me)2Ph. Reductive cleavage by hydroquinone, phosphines and phosphites are the slowest of all RuTPP[O(FeN4)]2 systems studied to date (t1/2 = 8 h at 40°C).
- Zobi,Stynes
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p. 795 - 801
(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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- 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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- Hydrolysis of phosphotriesters: Determination of transition states in parallel reactions by heavy-atom isotope effects
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The remote label method was used to measure primary and secondary 18O isotope effects in the alkaline hydrolysis of O,O-diethylphosphorylcholine iodide (DEPC) and the primary 18O effect in the alkaline hydrolysis of O,O-diethyl-m-nitrobenzyl phosphate (DEmNBP). Both the leaving group of interest (choline or m-nitrobenzyl alcohol) and ethanol can be ejected during hydrolysis due to the similarity of their pK values. The heavy-atom isotope effects were measured by isotope ratio mass spectrometry. Parallel reaction and incomplete labeling corrections were made for both systems. DEPC has a primary 18O isotope effect of 1.041 ± 0.003 and a secondary 18O isotope effect of 1.033 ± 0.002. The primary 18O isotope effect for DEmNBP was 1.052 ± 0.003. These large effects suggest a highly associative transition state in which the nucleophile approaches very close to the phosphorus atom to eject the leaving group. The large values are also indicative of a large compression, or general movement, on the reaction coordinate.
- Anderson,Shim,Raushel,Cleland
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p. 9246 - 9253
(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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- Reaction of three-coordinate phosphorus compounds with organophosphorus pseudohalogens. Part 4. The mechanism of interaction between bis(phosphinoyl) diselenides [R1R2P(O)Se]2 with three-coordinate phosphorus compounds
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The reaction of bis(phosphinoyl) diselenides R1R2P(O)Se-SeP(O)R1R2 1 with P(III) compounds has been investigated and its mechanistic features have been elucidated by variable temperature 31P NMR spectroscopy. These studies show that in most cases phosphonium intermediates [>P(O)-Se-P+-O-P(Se)P(Se)-O-P+-O-P(Se)a phosphorane intermediate is observed. In the isomerization 7→10 and 13→16 the pathway of decomposition (deselenization, deoxygenation or dealkylation) to give stable end products is influenced by electronic and steric factors.
- Krawczyk, Ewa,Skowronnska, Aleksandra,Michalski, Jan
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p. 1135 - 1140
(2007/10/03)
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