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1.
S. Bakkas A. Mouzdahir L. Khamliche M. Julliard E. Péralez M. Chanon 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):211-224
Abstract The reaction of triethylphosphite 1 with diethyltrichloromethylphosphonate 2b in the absence of solvents and catalysts yields mainly diethyl(1,1-dichloropropyl)phosphonate 4 and diethyldichloromethylphosphonate 7. These main products are accompanied by a variety of by-products which differ considerably from those obtained in the reaction between triethyl phosphite and CCl4. Both reactions would begin by a halophilic substitution of triethylphosphite on the positive halogen. For diethyltrichloromethylphosphonate 2b the formed carbanion would then attack preferentially the carbon β to P+ and the hydrogen γ to P+ on heterophosphonium cation. In contrast, the less sterically hindered trichloromethyl carbanion formed by the halophilic attack of triethylphosphite on carbon tetrachloride would rather attack mainly the positive P+ of this cation. The tetraethyl(dichloromethylene)bisphosphonate 8 previously reported by Kukhar and Sagina to be the main product formed in the thermal reaction between triethylphosphite and diethyltrichloromethylphosphonate was not found under our conditions. We observed its formation only under photochemical irradiation. 相似文献
2.
Claude Lion Louis da Conceição Gerard Hecquet Christian Pralus Jean-Pierre Schirmann Benoît Requieme 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1131-1152
L'action de l'acide perpropionique CH3CH2CO3H (1) a été étudiée en milieu alcalin micellaire (pH ~ 11; chlorure de cétyl triméthyl ammonium, CTACl) sur le thioanisole (4) et sur ses dérivés p-substitués, le p-méthoxy (2), le p-méthyl (3), le p-bromo (5) et le p-nitro (6). L'oxydation conduit exclusivement aux dérivés sulfoxydes (2a–6a). Les effets du pH, de la substitution et de la température ont permis de mieux comprendre la réaction d'oxydation de ces sulfures en sulfoxydes par l'acide perpropionique. Des calculs ab initio ont montré la cohérence de nos hypothèses. Enfin l'influence du milieu sur la cinétique de la réaction a été évalué en phase aqueuse (pH ~ 11) en présence de CTACl. The reaction of perpropionic acid CH3CH2CO3H (1) with thioanisole (4) and p-substituted thioanisoles [p-methoxy (2), p-methyl (3), p-bromo (5), and p-nitro (6)] in stoechiometric proportion has been carried out in micellar medium (cetyl trimethyl ammonium chloride, CTACl). Studies of the influence of the pH, the temperature and the substitution of the thioanisole, provide a better understanding of the sulfoxides (2a–6a) formation. Ab initio calculations have been achieved and the oxidation reaction has been studied in detail in aqueous medium (pH = 11). 相似文献
3.
Ahmed Djellal et Abdelhafid Djerourou 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1123-1129
The protection of the hydroxy group of p-cresol 1 by o-silylation gives derivatives 2 and 3 , the methyl group of which can be brominated by NBS. The phase transfer catalysis applied to 4 and 5 is a good way which permits the mild introduction of the allylthio group ( 6 and 7 ). Hydroboration applied to silylated compounds 8 and 9 , followed by methanolysis and hydrolysis leads to target acids 10 and 11 in a good yield. La protection du groupement hydroxy du p-crésol 1 par o-silylation donne les dérivés 2 et 3 ce qui permet de bromer le substituant méthyle par le N-bromosuccinimide (NBS). La catalyse par transfert de phase (CTP) appliquée aux produits 4 et 5 est une bonne méthode pour introduire un groupement allylthio (composés 6 , 7 ). L'hydroboration des composés silylés 8 et 9 , suivie d'une méthanolyse et d'une hydrolyse permet d'accéder aux acides cibles 10 et 11 avec de bons rendements. 相似文献
4.
Elie Elia Aboujaoude Noöl Collignon Philippe Savignac 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):231-243
Abstract On rélise la synthése d'hétérocycles α-phosphoniques par condensation de bis-nucléophiles-1,2, -1,3 et -1,4 avec des énamines β-phosphoniques 2 portant un groupe fonctionnel [C(O)R, C(O)OC2H5, CN]. Avec la guanidine. l'acétamidine, la S-méthyl-isothiourée et l'acéomalonimide on prépare les diétho[xacute]yphosphinyl-4 pyrimidines 5 et 8 avec des redements supérieurs á 50%. Les hydrazines substitutées conduisent aux diéthoxyphosphinyl-4 pyrazoles 11 α plus de 90%. Avec l'hydroxylamine, on obtient par déshydratation spontanée de l'intermédiaire réactionnel l'énol du β-cétophosphonate α-nitrile 18. Dans le cas de l'orthophényléne diamine la réaction ne donne pas la diazépine 23 mais évolue vers la régénération du β-cétophosphonate de départ par élimination de benzimidazole. Synthesis of α-phosphonic heterocycles is described by condensation of 1,2- 1,3- or 1,4-bis-nucleophiles with β-phosphonic enamines 2 bearing a functional group. From guanidine and analogs 4-diethoxyphosphinyl pyrimidines 5 and 8 are obtained with yields up to 50%. Substituted hydrazines give 4-dietho-xyphosphinyl pyrazoles 11 with very good yields. With hydroxylamine a spontaneous dehydration gives the enolic form 18 of a β-ketophosphonate α-nitrile. Orthophenylene diamine is a special example in fact the departure β-ketophosphonate is recovered with benzimidazole elimination. 相似文献
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Henri-Jean Cristau Denis Bottaro Françoise Plénat Francine Pietrasanta Et Henri Christol 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):63-71
Abstract Vinylene-1,2 bisphosphoniums salts react, in the presence of a base, with compounds ZH having a mobile hydrogen, to give a way of synthesis of β-substituted vinylphosphoniums salts 2 or β-disubstituted alkylphosphoniums salts 3. We have studied the limits of these synthesis depending on the experimental conditions and the nature of compounds ZH (alcohols, phenols, thiols, phosphines, amines). Les sels de vinylène-1,2 bisphosphoniums réagissent, en présence d'une base, avec les composés à hydrogène mobile ZH pour fournir ainsi une méthode d'obtention de sels de vinylphosphoniums β-substitués 2 ou de sels d'alkylphosphoniums β-disubstitués 3. Nous avons étudié les limites de ces synthèses en faisant varier les conditions opératoires et la nature des composés ZH (alcools, phénols, thiols, phosphines, amines). 相似文献
13.
Frederic Dujols Michel Mulliez 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):165-191
Abstract Derivatives of β aminoacids in form of esters 1 or nitrile 4 (table I) undergo in an alcohol-ate/alcohol medium a rearrangement (Fig. 2), with formation of a β peptide link, resulting in the formation of esters 6 (table II). According to the experimental conditions the six membered ring heterocycles 5 are detected or isolated. They are also synthetized by cyclisation of acids 2 or hydrazide 3 (Fig. 5). While phosphorus easily reacts with alcohols and water, leading respectively to esters 6 and acids 9 (Fig. 7), it remains unaffected by amines. These results are discussed in term of mechanisms of the phosphorylation. The applications for β peptide synthesis and the participation of the p amide group in phosphorylation are limited. 相似文献
14.
《Comptes Rendus de l'Academie des Sciences Series IIC Chemistry #》1999,327(7):701-708
A testing system has been developed at the Institut d'astrophysique spatiale with the Orsay synchrotron facility, in order to perform a full calibration of the EPIC spectro-imaging instrument, which is due to be launched on board the XMM satellite the 21st of January 2000. Dealing with one of the most advanced devices among X-rays detectors using CCD technology, the challenge has been to find the more accurate techniques (cryogenics, high energy optics…) and real-time operating systems (multitask computer environment) to achieve our calibration purposes. 相似文献
15.
Jean-Paul Silvestre Nguyen Quy Dao et Pascale Salvini 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):771-779
The organic complex salt [H 3 N--CH 2 --CH 2 --NH 3 ][C(CH 3 )(OH)(PO 3 H 2 )(PO 3 H)] 2 is obtained by reaction between the hydroxyethylidenebisphosphonic acid (HEBP) and the ethylenediamine (EDA) in aqueous medium. This compound, the first where the cation is an organic base, crystallizes with the monoclinic space group P2 1 / c (n°;14) and a = 6.867(1) Å, b = 11.665(2) Å, c = 10.977(2) Å, g = 101.85(4)°;, V = 861.2(2) Å 3 , Z = 2. The cohesion of the crystal structure is assumed exclusively by a dense network of hydrogen bonds between two HEDP m and between one HEDP m and one EDA 2+ . 相似文献
16.
N. H. Ahabchane E. M. Essassi J. Bellan L. Lopez L. Lamandé 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):175-192
Abstract De nouveaux macrocycles de structures variées, renfermant une ou deux unités pyrazolylbenzimidazoles au sein d'une cha[icaron]ne polyéthylèneglyco1 ont été préparés par condensation, en catalyse par transfert de phase solide-liquide, de la 1-[3(5)-phénylpyrazol-5(3)-yl] benzimidazole-2-thione 1 avec le dichlorotétraéthylèneglycol 4 d'une part, et du 1,8(1,11)bis-[1-[3(5)-phtnylpyrazol-5(3)-yl] benzimidazol-2-yl]mercapto tri (tétra) glycol 9(10) avec les dichloropolyéthylèneglycols 3 et 4, d'autre part. 相似文献
17.
Abstract Cadmium trimetaphosphate tetradecahydrate powder has been studied by 1H nuclear magnetic resonance between ?191 and 60°C. The spectra includes one contribution from molecular water and one contribution from H atoms belonging to “OH” groups. The formula which agrees with these results is Cd3(OH) n (P3O9)2H n · (14- n )H2O; it seems that n increases with increasing values of temperature. L'étude par résonance magnétique du proton du trimétaphosphate de cadmium tetradécahydraté en poudre a été faite entre ?191 et +60°C. Le spectre comporte une contribution d'eau moléculaire et une contribution d'atomes H appartenant à des groupes OH. La formule en accord avec ces résultats est Cd3(OH) n (P3O9)2H n · (14- n )H2O, o[ugrave] n croit vraisemblablement avec la température. 相似文献
18.
Soufiane Touil Mohamed Taieb Ben Dhia Hedi Zantour Belgacem Baccar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):295-302
Abstract The Lawesson reagent (L.R) reacts with phenylhydrazones of ketones γ-disubstituted phosphonates and phosphine oxide 1 to give 1,2,3-diazaphospholine derivatives 2 and 2′. Two diastereomers were obtained in some cases. The structure of the products 2 and 2′ is confirmed by NMR and IR spectroscopy. 相似文献
19.
The intensity-potential curves pertaining to the oxidation of iodides, bromides and chlorides at a polished platinum electrode, undergo deformations when the following factors are varied: initial concentration of halogen, pH, addition of ions that complex or reduce the halogen formed. Analysis of these deformations has led us to assume that the electrochemical behaviour of the three halides can be represented by a reaction of the type: 2 x3--2e ? 3 x2 and not of the type: 2 x-- 2e ? x2 As far as bromides and chlorides are concerned the coulometric study agrees with this hypothesis 相似文献