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In reaction with benzothiophene, t-butyl hypochlorite acts as an oxidizing reagent and a chlorination reagent. A mixture of 3-ehlorobenzothiophene, three 2,3-dichloro-2,3-dihydrobenzothio-phene 1-oxide isomers (trans-anti: trans-syn; cis-anti) and 2-chlorobenzothiophene 1-oxide was obtained. With a large exces of t-butyl hypochlorite, the reaction leads to 2,3-dichlorobenzothio-phene, 2,3-dichlorobenzothiophene 1-oxide. 2,2,3-trichloro-2,3-(lihydrobenzothiophene 1-oxide and 2,3-dichloro-3-oxobenzothio-phene 1-oxide. In any case, oxidation stops at the level of the sulfoxide. 相似文献
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Ta Chi Chiang Ch. Graillat J. Guillot Q. T. Pham A. Guyot 《Journal of polymer science. Part A, Polymer chemistry》1977,15(12):2961-2970
Two sets of methylmethacrylate-vinylidene chloride copolymers were prepared via radical copolymerization in dimethylformamide. The first set is carried out in batches. Gas-chromatographic analysis of samples allows a kinetic study from which the reactivity ratios rM - 2.73 and rC - 0.24 are derived. For the second set a new apparatus, briefly described, has been used. It permits to keep constant the composition of the monomer mixture, through addition of methyl methacrylate, monitored by a chromatographic analysis. The two sets of copolymers are analyzed using nuclear magnetic resonance (60 MHz) leading to the triad distribution, from which the reactivity ratios are derived. Owing to the composition drift, the method cannot be applied to the first set of copolymers; but in that case, it is possible to calculate the triad distribution, the knowledge of the reactivity ratios, and the calculation fits quite well the experimental results. 相似文献
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Rausa Arshinova Raymond Kraemer Jean-Pierre Majoral Jacques Navech 《Magnetic resonance in chemistry : MRC》1975,7(7):309-312
Two phosphorus heterocycles are studied by means of 1H NMR and IR spectroscopy. The ring conformation is discussed and the torsional angle of the C-5—C-6 fragment is calculated for one of them. 相似文献
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A. Merbach 《Helvetica chimica acta》1967,50(5):1431-1435
In a solution containing an excess of two metal ions in regard to a ligand (e.g. NTA) a competitive equilibrium is established. The measure, by proton NMR. spectroscopy, of the individual concentrations of both chelates, and eventually of the free ligand, allows to determine the ratio of the stability constants of the two complexes. As an illustration the ratios of the stability constant of the 1:1 nitrilotriacetate chelates of Pb and Zn, respectively Mo and W, were determined. 相似文献
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The reactions between phenylmagnesium bromide or benzylmagnesium chloride and titanium tetrachloride have been studied. The influence of the introduction order of the reagents is mentioned. Decomposition of the (non-isolated) compounds RnTiX4-n is shown to be essentially intermolecular, and rarely intramolecular. 相似文献
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Saturnin Claude Raffaele Tabacchi Laurent Due Rudolf Fuchs Karl-Josef Boosen 《Helvetica chimica acta》1980,63(3):682-692
Study of Electron-Impact Fragmentation of Benzothiazole Derivatives The mass spectra of eighteen substituted benzothiazoles are reported and discussed. All these compounds are thermodynamically stable and give an intense molecular ion, which undergoes different types of fragmentation depending on the nature of the substituent which is rarely eliminated directly. β-Cleavage with respect to the heterocyclic double bond is often observed. Specific 2H-, 13C-, 15N- and 34S-labelling have been used in order to confirm the fragmentation patterns. 相似文献
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Samir Qourzal Malika Tamimi Ali Assabbane Yhya Ait-Ichou 《Comptes Rendus Chimie》2007,10(12):1187-1194
TiO2 photocatalytic mineralization of β-naphthol: influence of some inorganic ions, ethanol, and hydrogen peroxide. In this work, the photocatalytic oxidation of β-naphthol in aqueous suspensions of TiO2 was investigated at room temperature, by following the formation of CO2. The disappearance of β-naphthol fits a Langmuir-Hinshelwood kinetic model. The activation energy for the degradation reaction of β-naphthol is estimated at 10.2 kJ/mol. The effects of some additives such as ethanol, H2O2, and inorganic ions (Cl−, SO42−, HCO3−, NO3−, Fe3+, Cu2+, and Cr3+) on the photomineralization of β-naphthol were examined. The inhibition of the anions for this reaction was in the order : NO3− < HCO3− < SO42− < Cl−. This can be due to a partial blockage of catalyst active sites by these ions or their reaction with an oxidizing radical such as OH. The most photoactive systems for β-naphthol degradation were found in the presence of ferric ions, while the addition of Cr3+ strongly inhibited the photocatalytic decomposition of β-naphthol. 相似文献