- New Triazole-Containing Branched Bis(dipeptidomimetic) - Switching from Self-Dimerization to Anion-Binding Properties
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A triazole-containing branched bis(dipeptidomimetic) 2 using l -lysine as a flexible branching unit was synthesized and characterized. The compound was found to form weak dimers (K dim = 19 M -1) in chloroform as shown by vapor pressure osmometry (VPO) and concentration-dependent 1 H NMR studies. On the other hand, the compound was capable of binding chloride and monobasic diethyl phosphate (DEP) in chloroform. Job plot analysis, MALDI-TOF mass spectrometry, and NMR titration studies revealed a 1:1 binding stoichiometry with good binding affinities (K a ≈ 640-780 M -1). Structural studies using ROESY NMR spectroscopy and molecular modelling on the 2 -DEP complex indicated the adoption of a helix-like conformation by the host with the guest situated near the branching juncture.
- Chui, Tin-Ki,Chow, Hak-Fun
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- The Preparation and the Use of 2-Chloro-2,4-dioxo-3-methyl-1,3,2-thiazaphospholidine, a Highly Reactive Reagent for the Synthesis of S-(N-Methylcarbamoylmethyl) Dialkyl Thiophosphates and Dialkyl Sodium Phosphates
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The synthesis of 2-chloro-2,4-dioxo-3-methyl-1,3,2-thiazaphospholidine (4), a versatile and highly reactive reagent for the synthesis of unsymmetrical S-(N-methylcarbamoylmethyl) dialkyl thiophosphates and dialkyl sodium phosphates, and several reactions with alcohols are reported.
- Richter, Wolfgang,Ugi, Ivar
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- Cetyltrimethylammonium hydroperoxide: An efficient reagent for promoting phosphate ester hydrolysis
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Cetyltrimethylammonium hydroperoxide solutions are easily prepared by mixing cetyltrimethylammonium hydroxide and hydrogen peroxide and are very efficient in promoting paraoxon (diethyl p-nitrophenyl phosphate) hydrolysis.
- Toullec, Jean,Moukawim, Mohamed
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- 1-Oxo-2-oxa-1-phosphabicyclo[2.2.2]octane: A new mechanistic probe for the basic hydrolysis of phosphate esters
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Synthesis of the title compound 2 was accomplished in a multistep sequence starting from hypophosphorous acid. In strong base, the bicyclic phosphinate 2 hydrolyzes 2 orders of magnitude faster than the bicyclic phosphate OP(OCH2)3CCH3 (1a) and the acceleration is entirely enthalpic. This rate enhancement is attributed to the greater ease with which 2 achieves the five-coordinate transition state. The molecular structure of 2, determined by X-ray means, compared with that of 1a reveals no evidence of strain within either bicyclic framework. The observed acceleration does not support the contribution of a stereoelectronic effect in the hydrolysis of six-membered ring phosphates.
- Wróblewski, Andrzej E.,Verkade, John G.
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- Predicting the hydrolytic breakdown rates of organophosphorus chemical warfare agent simulants using association constants derived from hydrogen bonded complex formation events
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Organophosphorus (OP) chemical warfare agents (CWAs) represent an ongoing global threat, through either purposeful environmental release or the need to dispose of historic stockpiles. This presents a need for the development of novel decontamination technologies. Due to the toxic nature and legal limitations placed on OP CWAs, the use of appropriate OP simulants that mimic the reactivity but not the toxicity of the agents themselves is vital to decontamination studies. Herein, we show that association constants derived from non-specific hydrogen bonded complexation events may be used as parameters within models to predict simulant reactivity. We also discuss the limitations that should be placed on such data.
- Chu, Dominique F.,Clark, Ewan R.,Ellaby, Rebecca J.,Hiscock, Jennifer,Pépés, Antigoni
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- Synthesis and reactivity of substituted α-carbonylphosphonites and their derivatives
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Convenient methods for the synthesis of functionalized organophosphorus compounds containing carbonyl groups as well as di- or trialkoxymethyl fragments attached to phosphorus, and their derivatives, starting from the available derivatives of trivalent phosphorus acids, are proposed, and some properties of the new functionalized organophosphorus compounds are presented. So, the alkylation and acylation reaction of (dialkoxymethyl) phosphonites and their analogs have been studied. It is found that the Arbuzov rearrangement of these compounds was accompanied by the phosphorus-carbon bond cleavage with unique retention of the three-coordinate phosphorus.
- Prishchenko, Andrey A.,Livantsov, Mikhail V.,Novikova, Olga P.,Livantsova, Ludmila I.,Petrosyan, Valery S.
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experimental part
p. 352 - 372
(2012/08/28)
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- Destruction of toxic organophosphorus and organosulfur pollutants by perpropionic acid: The first stable, industrial liquid water-miscible peroxyacid in decontamination
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Use of commercial perpropionic acid (PPA), the first stable, industrial and water-miscible peroxyacid, allows the destruction of toxic organophosphorus and organosulfur compounds under micellar conditions. The destruction of paraoxon (O,O-diethyl O-p-nitrophenylphosphate), di-n-butyl sulfide and 2-chloro-2′-phenyldiethyl sulfide has been studied.
- Lion, Claude,Da Conceicao, Louis,Hecquet, Gerard,Pralus, Christian,Requieme, Benoit,Schirmann, Jean-Pierre
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p. 1515 - 1518
(2007/10/03)
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- New ω-phthalimidoperoxyalkanoic acids in decontamination. Destruction of some toxic organophosphorus and organosulfur pollutants
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Chemical decontamination of toxic compounds (chemical warfare agents and/or insecticides) is of increasing importance. In this study, we report the use of ω-phthalimidoperoxyalkanoic acids 2 in the destruction of paraoxon (O,O-diethyl-O-para-nitrophenylphosphate), a well-known insecticide, and 2-chloro-2′-phenyldiethyl sulfide (a half mustard). We show that while all the peroxyacids used in this series allow the destruction of toxic compounds, the length n of the alkanoic side chain is important to the choice of the optimal industrial compound, which is 2d (n = 5).
- Lion,Da Conceicao,Delmas,Magnaud
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p. 1182 - 1184
(2007/10/03)
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New initiators 1-7, analogues of tetra-acetylethylenediamine, have been prepared and their use in the in situ generation of peroxyacids by reaction with sodium peroxycarbonate described. The kinetics of perhydrolysis of these initiators in aqueous solutio
- Lion, Claude,Da Conceicao, Louis,Hedayatullah, Mir
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- Free-Radical Phosphorylation of Olefins Initiated by Anodic Oxidation
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Electrochemical oxidation of lithium and sodium dialkyl phosphites generates dialkyl phosphonyl radicals, which initiate chain free-radical addition of dialkyl phosphites across the alkene multiple bond to form alkyl(cycloalkyl)phosphonates. Alkyl(cycloalkyl)phosphonates are formed simultaneously owing to anodic oxidation of adsorbed primary radical adducts of phosphonyl radical and alkene molecule to give the carbenium cation, followed by deprotonation of the latter.
- Romakhin,Kosachev,Zagumennov,Nikitin
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p. 227 - 234
(2007/10/03)
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- α-HALOGENO SULPHOXIDES AS AMBIDENT ELECTROPHILES TOWARDS DIALKYL PHOSPHITE ANIONS
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α-Halogenomethyl alkyl(aryl) sulphoxides have been found to undergo nucleophilic attack by dialkyl phosphite anions at the α-carbon atom and/or at halogen.
- Mikolajczyk, Marian,Zatorski, Andrzej
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p. 323 - 324
(2007/10/02)
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- NOUVEAUX DECONTAMINANTS. DESTRUCTION DE TOXIQUES ORGANOPHOSPHORES OU SOUFRES PAR DES PERACIDES MONO-, BI- ET TRICYCLIQUES SATURES
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New peroxycarboxylic and peroxyacetic acids have been tested for the destruction of some organophosphorus compounds and mustards.The peroxyacids used have monocyclic, bicyclic or tricyclic structures.These are very reactive against paraoxon or HD and the addition of certain surfactants enhances the reaction rate.Very short half-live times are obtained with these compounds.
- Lion, C.,Hedayatullah, M.,Bauer, P.,Boukou-Poba, J. P.,Charvy, C.,et al.
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p. 249 - 256
(2007/10/02)
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- Anomalous Michaelis-Becker Reaction: 1-Phenylethan-1,2,2-triphosphonic Acid and their Esters
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Sodium dialkylphosphite reacts with trichlorovinylbenzene to yield in an one-batch procedure 1-phenyl-1,2,2-ethanetriphosphonic acid hexaalkyl esters.A carbanionic intermediate of an "anomalous Michaelis-Becker reaction" is deduced.Acidolysis of esters leads to the parent triphosphonic acids.NMR parameters of this acid are strongly influenced by protolytic equilibrium. - Key words: One-batch synthesis, Oligophosphonic Acid, NMR Spectra
- Fischer, Ulrich,Haegele, Gerhard
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p. 1152 - 1156
(2007/10/02)
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- New Olefin and Oxiran Syntheses from Carbonyl Compounds, and Diethyl Sodiophosphonate Anions and 1-Aminophosphonate Amino-anions
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Reaction of aromatic aldehydes, and phthalic and thiophthalic anhydrides, with diethyl sodiophosphonate (1) gives the trans-stilbenes (3), 3,3'-biphthalidylidene (30), and 3,3'-bis-(2-thiophthalidylidene) (33).Similar treatment of fluorenone (8) and xanthone (17) with (1) leads to 9,9'-bis(fluororenylidene) (9) and 9,10-dihydro-9-oxophenanthrene-10-spiro-9'-fluorene (10), and to 9,9'-bixanthenylidene (18) and 9,9'-bixanthenyl (19), respectively, but the reaction using anthrone (11) as a carbonyl reagent yields only anthraquinone (12) and anthracene (13).Similar treatment using N-methylisatoic anhydride (34) and N-methylisatin (36) produces NN'-dimethylisoindigo (35).Reaction of benzaldehyde and p-chlorobenzaldehyde with diethyl 1--cyclohexylphosphonate (40) gives mainly corresponding mixtures of trans- (41a,b) and cis-stilbene epoxides (42a,b), while similar treatment of p-nitrobenzaldehyde with (40) produces 4,4'-dinitrostilbene (3e).Reaction of (8) with (40), as well as with (1), gives (9) and (10).The mechanism of formation of these products is discussed.
- Minami, Toru,Matsuzaki, Narihide,Ohshiro, Yoshiki,Agawa, Toshio
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p. 1731 - 1738
(2007/10/02)
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