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Xanthates were easily prepared by adsorption of alcohol on KF-Al2O3 followed by treatment of carbon disulfide and iodomethane at room temperature. Pyrolysis of benzyl xanthate affords to a complex mixture of products. A radical process was proposed to explain the nature of products obtained. 相似文献
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Abdelhamid Elias M. Amine Didi Didier Villemin T. Semaoune S. Ouattas 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2599-2607
The reactions of phosphorus pentoxide with two alcohols and one phenol were performed in different conditions under microwave irradiation. The products (alkylphosphates and dialkylphosphates) were identical to those formed by classic heating and were obtained with better yields. The speed of the reaction was increased by a factor from 100 to 4000. 相似文献
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1,4-Diacetylpiperazine-2,5-dione (1) was condensated with aldehydes (2) with KF on alumina without solvent under microwaves or in at room temperature in the presence of DMF. The reaction was stereoselective and some natural products (4a-c) like albonursin(4c) were synthesized. 相似文献
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Cyclohexanone and morpholine in the presence of KSF under azeotropic distillation gave 1-morpholinocyclohexene which is alkylated or acylated in situ without isolation of the enamine. The overall yield of these Stork's reactions are better or equivalent to those obtained by isolation of the enamine. 相似文献
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Tabbi Hanane Amel Bendjeddou Didier Villemin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):697-704
AbstractThe synthesis of the title compounds has been carried out by condensation via a Wittig-type reaction of a pyridinium hexafluorophosphate with a phosphonate ester to give the desired (4-nitrophenyl)tetrathiafulvalene the nitro group of which was reduced to an amino group. Reaction of the amine with chlorosulfonyl isocyanate and subsequently with tert-butyl alcohol gave the corresponding open-chain sulfamide. Cyclization under basic conditions and de-protection led to 2-[4-(4′,5′-dipropyltetrathiafulvalen-4-yl)]phenyl-1,2,6-thiadiazinane 1,1-dioxide. Finally, N-alkylated and N-acylated cyclic sulfamides linked to tetrathiafulvalene were obtained. Their electron donor ability was measured by cyclic voltammetry. A detailed DFT study based on B3LYP/6–31G (d,p) of electronic properties is also presented. The calculated molecular electrostatic potential shows that, the negative charge covers the nitro and sulfamide function, while positive charge is located at the hydrogen atoms of the amine and sulfamide rings. The calculated HOMO and LUMO energy reveals that charge transfer occurs within the molecule. The chemical reactivity parameters reveal that tetrathiafulvalene 1 is highly reactive, which facilitates the desired formation of the cyclic sulfamide. The first hyperpolarizability βtot shows that compounds 1 and 5 are good candidates as a NLO material. 相似文献
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Fatiha Zaoui Mohamed Amine Didi Didier Villemin 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(1):419-424
A new 8-hydroxyquinoline derivative extractant was synthesized via the Mannich reaction from a secondary amine. Various analytical techniques (1H, 13C NMR, FTIR, mass spectroscopy) were used to characterize our product. The use of this new extractant for the uptake and removal of uranyl ions in aqueous solution was investigated. Conditions for an effective sorption were optimized with respect to different experimental parameters in batch process. The results showed that the extraction rate increases for solutions with a pH in the range [0.65–1.13]. The total sorption capacity was 105 (mg g?1) under optimum experimental conditions. The extraction of UO2 2+ was found to be quantitative (100 %) at initial uranyl concentration less than or equal to 41.59 mg/L. Thermodynamic parameters showed the adsorption of an endothermic process and a spontaneous nature, respectively. 相似文献
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With a view to elucidating the mode of action of tungsten containing catalyst of the olefin metathesis, the thermal decomposition of various alkyltungsten derivatives was examined. It was shown that n-alkyltungsten derivatives (i.e. n-alkylmagnesium halides + WCl6) are decomposed to lighter alkenes and alkanes (i.e. propyl to ethylene, ethane and methane). With methyl or neopentyl derivatives of tungsten, alkenes are observed, which derive from alkylation and fission of the metathesis substrate (i.e. Me3CCH2MgBr + WCl6 + 2-pentene give inter alia 2,2-dimethyl-4 hexene). Metathesis of tetramethylethylene was also observed, as evidenced by the formation of 2-methyl-2-pentene in the presence of 3-hexene.All these facts agree with the intermediacy of a tungsten hydride as the key step in the formation of a metathesis catalyst, intermediacy which is linked with the formation of tungstacarbene (alkylidene tungsten). 相似文献
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