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11.
The composition and structure of an oligomer has been studied, formed in the reaction of elemental phosphorus (P4) with propylene oxide, phenol, and triethylamine in the ratio 150.81. It has been found by using mass spectrometry, IR and31P NMR spectrometry, chromatography and ebulliometry that the oligomer represents a chain consisting of fragments of isopropylphosphonous acid. Products of side reactions have been identified.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2244–2247, October, 1989.  相似文献   
12.
The reactions of 1,3-bis(-bromobutyl- or -pentyl)-6-methyluracil with 1,3-bis(-ethylaminobutyl- or -pentyl)-6-methyluracil afforded pyrimidinophanes containing N atoms in bridging polymethylene chains. Individual geometric isomers of pyrimidinophanes were isolated. The structure of one of these isomers was established by X-ray diffraction analysis. Quaternization of the bridging N atoms with o-nitrobenzyl bromide gave rise to water-soluble pyrimidinophanes.  相似文献   
13.
Catalytic electroreduction of several substituted gem-dihalocyclopropanes was studied in the presence of metal salen-complexes by polarography, cyclic voltammetry, and preparative electrolysis. Monohalocyclopropanes (54—59%) and the corresponding allene (5—9%) were the main reduction products. The reaction rate constants were determined. The inner-sphere electron transfer was shown to occur under these conditions.  相似文献   
14.
Phosphorylacetic acid esters containing the menthoxy fragment at the phosphorus atom or at the carbonyl group were synthesized. The configurations of the enantiomerically pure compounds, viz., methyl (ethoxy)(menthyloxy)phosphorylacetate and menthyl [(2-chloro-ethoxy)(4-dimethylaminophenyl)phosphoryl]acetate, were established by X-ray diffraction and NMR spectroscopy. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 281–288, February, 2007.  相似文献   
15.
The reaction of 1,2-ethanedithiol with diethyl vinylphosphonate in the presence of EtONa occurs as the addition of the sulfhydryl group to the β-carbon atom of the substrate to give 1 : 1 and 1 : 2 adducts. The nucleophilic addition of 2-mercaptoethanol at the β position of the multiple bond of diethyl vinyl-, diethyl allenyl-, and diethyl prop-1-ynylphosphonates involves only the sulfhydryl group.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2156–2159, October, 2004.  相似文献   
16.
Abstract

The synthesis and structure of thiacalix[4]monocrowns in 1,3-alternate configuration substituted by terpyridyl fragments on the lower rim are being discussed. It has been shown that the number of oxyethylene units in oligoethylene glycol chain affects the distribution of the yields of the cross-linking products leading to either thiacalix[4]monocrowns or bisthiacalix[4]arenes. Their complexation ability towards alkali metal and lanthanide ions has been studied using liquid extraction and MALDI TOF MS, in addition to luminescent properties of ligands and their lanthanide complexes. The NMR titration data discovered the participation of both crown ether and terpyridyl fragment in the coordination of lanthanide cations. The fluorescent titration showed the nonlinear emission response to the amount of lanthanide ions.  相似文献   
17.
New chromatographically pure monoand hexamethanofullerenes C60 and C70 containing active allylic groups were synthesized by Bingel—Hirsch reaction. These compounds are promising for the studies of biological activity, as well as for obtaining on their basis new fullerenecontaining materials. The purity and composition of the synthesized compounds were confirmed by MALDI-TOF mass spectrometry and HPLC, their structure was established by 1H and 13C NMR spectroscopy and X-ray diffraction.  相似文献   
18.
Some compounds containing mono- and polynitroxide radicals have been investigated and characterized by electron ionization (EI), chemical ionization (CI), and matrix-assisted laser desorption-ionization (MALDI) mass spectrometry. Some characteristics of the mass spectra of these radicals are demonstrated. It was found that, under CI and MALDI conditions, ions [M+nH]+ are formed along with monoprotonated molecules [M+H]+, depending on the type of the radical n = 2–5.  相似文献   
19.
The “click-chemistry” methods were used for the first time to synthesize new 1,2,3-triazole derivatives of fullerene, promising for the study of their biological activity, as well as for the preparation of new fullerene-containing materials on their basis. The purity and composition of the compounds synthesized were confirmed by MALDI-TOF mass spectrometry and HPLC, their structures were confirmed by a combination of 2D NMR homo- and heteronuclear correlation.  相似文献   
20.
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