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141.
Convenient selective methods of synthesis of the title compounds, based on oxidation of di(propen-1-yl)sulfide with 30% H2O2, have been developed.Institute of Organic Chemistry, Siberian Branch, Russian Academy of Sciences, 664033 Irkutsk. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 675–679, March, 1992. 相似文献
142.
Heinz Falk Karl Grubmayr Martha Marko 《Monatshefte für Chemie / Chemical Monthly》1989,120(8-9):771-779
Summary A violinoid and a 2,3-dihydrobilindione chromophore is attachedvia an appendix anchored at rings A of the pigments by means of reacting them with the polyacryl-N-acryloxysuccinimid copolymer to yield water-soluble chromopolymers. They are characterized by a molecular mass of about 4000 to 6000 and a relation of one chromophoric unit per 6 to 22 monomers. Their absorption spectra and circular dichroism recorded in water and dimethylsulfoxide as solvents are discussed with respect to structural aspects, and in comparison with monomeric chromophore derivatives.
Herrn Prof. Dr. K. Schlögl mit den besten Wünschen zum 65. Geburtstag gewidmet 相似文献
143.
V. A. Shlyapochnikov L. S. Khaikin O. E. Grikina N. O. Cherskaya L. E. Maksimova N. F. Pyatakov 《Russian Chemical Bulletin》1998,47(11):2173-2176
Vibrational spectra of several nitramines in the long-wave region (50–450 cm−1) were studied. The frequencies of intra- and intermolecular vibrations were separated and a tentative assignment of the frequencies
of self-associative complexes was performed.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2241–2244, November, 1998. 相似文献
144.
The electron impact mass spectra of eleven N-arylglycines and seven substituted aniline-N,N-diacetic acids were obtained under 70 eV and 14 eV ionization energies. The fragmentation patterns are similar to those of α-amino acids except for the degree of cleavage. The dehydration process of the diacetic acids may be considered as the characterestic process for this group of compounds. 相似文献
145.
N. N. Zemlyanskii I. V. Borisova A. K. Shestakova Yu. A. Ustynyuk E. A. Chernyshev 《Russian Chemical Bulletin》1998,47(3):469-474
The first stable dibenzosilafulvene, 9-{[8-(dimethylaminomethyl)-1-naphthyl]phenylsil-1-ylium}fluoren-9-ide (7a), was obtained in one step from 9-fluorenyllithium and chloro[8-(dimethylaminomethyl)-1-naphthyl]phenylsilane as a stable
solvate with THF. The structure of the zwitterionic compound7a was established by1H,13C, and29Si NMR in solution and in the solid state. The reactions of compound7a with crotonaldehyde, ethanol, and triethylethylidenephosphorane are described. The data on the synthesis of alkoxy- and alkylthiochloro-9-fluorenylsilanes
and their phosphonium salts are given.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 486–491, March, 1998. 相似文献
146.
AnExplanationontheElectronIonizationMassSpectraofCrownEthersbyMNDOComputationalMethodYUANHu-shan,TANGMing-shengandWUYang-jie(... 相似文献
147.
微波辐照增强原煤磁分离脱硫机理探讨 总被引:5,自引:0,他引:5
采用~(57)Fe穆斯堡尔谱学方法,研究微波-磁分离法脱硫机理及微波辐照深度对脱硫率的影响。结果表明,微波选择性介质加热,可以激励煤中顺磁性黄铁矿FeS_2热解,使其转化为非化学计量的磁黄铁矿Fe_(1-x)S(0相似文献
148.
149.
Summary Procedures were developed for the preparation of the 2-, 3-, 4-, and 6-monosubstituted chloro and bromo 8-quinolinols which afforded greater yields and/or reduced the number of steps in the preparation. 100 MHz1H-NMR spectra for the 12 possible monochloro and monobromo analogues are given.
Verbesserte Synthese von Monochlor- und Monobrom-8-chinolinolen
Zusammenfassung Es wurden Verfahren entwickelt, um 2-, 3-, 4- und 6-Chlor bzw. -Brom-8-chinolinole in besseren Ausbeuten und/oder bei reduzierter Anzahl von Synthesestufen herzustellen. Die1H-NMR-Spektren der 12 möglichen Monochlor- und Monobromverbindungen werden angegeben.相似文献
150.
JIANG Qi-Jun 《结构化学》2005,24(10):1140-1144
1 INTRODUCTION The electron-transfer reaction of C60 derivatives, especially light-induced electron-transfer reaction, has been an active research field for a long time. Many researches are focused on the long-live charge- separated state caused by electron-transfer[1]. And several electron-transfers between electron donor and C60 or intramolecular electron-transfer have been confirmed. As an example, TTF-C60 is proved to be a short-live charge-separated compound[2].Due to the excelle… 相似文献