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91.
Andrey A. Prishchenko Mikhail V. Livantsov Olga P. Novikova Ludmila I. Livantsova Valery S. Petrosyan 《Heteroatom Chemistry》2010,21(2):71-77
Convenient procedures for the synthesis of new organophosphorus‐substituted mono‐ and bis(trimethylsilyl)amines with PCH2N moiety are proposed, starting from trimethylsilyl esters of organophosphorus acids, as well as 1,3,5‐trialkylhexahydro‐1,3,5‐triazines and N‐alkoxymethyl bis(trimethylsilyl)amines as aminomethylating reagents. Certain properties of the resulting compounds are presented. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:71–77, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20580 相似文献
92.
Andrey A. Prishchenko Mikhail V. Livantsov Olga P. Novikova Ludmila I. Livantsova Valery S. Petrosyan 《Heteroatom Chemistry》2010,21(6):430-440
The aminomethylation of the derivatives of trivalent organophosphorus acids, containing PH and POSiMe3 fragments with various bis‐ and tris(alkoxymethyl)amines and bis(alkoxymethyl)amino acids, is proposed as a convenient method for the synthesis of new bis‐ and trisphosphorylated amines and amino acids as well as their derivatives with four and five coordinated phosphorus. Also the three‐components systems of phosphorous acid, paraformaldehyde, and amines are thoroughly investigated via the treatment of reaction mixtures with bis(trimethylsilyl)amine. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:430–440, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20616 相似文献
93.
An efficient and selective multicomponent oxidative coupling of two different aliphatic primary amines into thioamides by elemental sulfur under solvent-free conditions has been developed. 相似文献
94.
Alexander S. Lyakhov Ludmila S. Ivashkevich Vladimir L. Survilo Tatjana V. Trukhachova 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(1):o33-o36
Crystals of bis(2‐ethyl‐3‐hydroxy‐6‐methylpyridinium) succinate–succinic acid (1/1), C8H12NO+·0.5C4H4O42−·0.5C4H6O4, (I), and 2‐ethyl‐3‐hydroxy‐6‐methylpyridinium hydrogen succinate, C8H12NO+·C4H5O4−, (II), were obtained by reaction of 2‐ethyl‐6‐methylpyridin‐3‐ol with succinic acid. The succinate anion and succinic acid molecule in (I) are located about centres of inversion. Intermolecular O—H...O, N—H...O and C—H...O hydrogen bonds are responsible for the formation of a three‐dimensional network in the crystal structure of (I) and a two‐dimensional network in the crystal structure of (II). Both structures are additionally stabilized by π–π interactions between symmetry‐related pyridine rings, forming a rod‐like cationic arrangement for (I) and cationic dimers for (II). 相似文献
95.
Vladimir Zakharov Mikhail Matsko Ludmila Echevskaya Tatiana Mikenas 《Macromolecular Symposia》2007,260(1):184-188
New experimental approach was used for analysis of molecular weight distribution (MWD) of polymers produced over titanium-magnesium catalysts (TMC). Polymers were fractionated on to fractions with narrow MWD (polydispersity (PD) values Mw/Mn ≤ 2). Then some of these fractions were combined to get the minimal quantity of fractions with PD values close to 2 (Flory components). It was found that three fractions corresponding to three groups of active centers are sufficient for proper fitting experimental MWD curve for PE obtained over TMC with different Ti content and with different hydrogen concentration in polymerization. 相似文献
96.
Alexander S. Lyakhov Pavel N. Gaponik Sergei V. Voitekhovich Ludmila S. Ivashkevich Alexander A. Kulak 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(10):1204-1206
There are two symmetry-independent molecules in the unit cell of the title compound, C7H5N5O3. The tetrazole and phenyl rings are essentially planar and are not coplanar in either molecule [dihedral angles 30.2 (1) and 7.0 (1)°]. In the structure, four molecules are connected by O—H⃛N bridges, forming four-membered molecular aggregates which are linked together by a complex three-dimensional hydrogen-bond network. 相似文献
97.
Alexander D. Vasiliev Alexander M. Astachov Yuri V. Kekin Ludmila A. Kruglyakova Rudolf S. Stepanov 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(10):1192-1193
The molecule of title compound, C2H7N3O2, has a zwitterionic structure. All non-H atoms, apart from the terminal N atom of the NH3 group, lie in the same plane, with a maximum deviation of 0.056 (1) Å for the amine N atom of the nitramine group, whereas the deviation of the terminal N atom of the NH3 group from the same plane is 1.222 (2) Å. Intermolecular hydrogen bonds within the crystal form a three-dimensional network. 相似文献
98.
Dr. Ludmila Krejčová Dr. Terza Leonhardt Dr. Filip Novotný Dr. Vilém Bartůněk Dr. Vlastimil Mazánek Prof. David Sedmidubský Prof. Zdeněk Sofer Prof. Martin Pumera 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(15):3828-3834
Nature and its highly sophisticated biomaterials are an endless source of inspiration for engineers and scientists across a wide range of disciplines. During the last decade, concepts of bioinspired synthesis of hierarchically structured nano- and micromaterials have been attracting increasing attention. In this article, we have utilized the natural ability of fungi to absorb metal ions for a bioinspired synthesis of carbonaceous material doped by selected transition metals. As an all-around metal accumulator, Hebeloma mesophaeum was selected, and it was cultivated in the presence of three transition-metal ions: NiII, FeII, and MnII. The metal-doped carbonized biomaterial possessed enhanced catalytic activity toward hydrazine oxidation, oxygen reduction, and cumene hydroperoxide reduction. Thus, we have shown possible transformation of a waste product (fungi grown on a contaminated soil) into a value-added carbonaceous material with tailored catalytic properties. This bioinspired synthesis can outline an attractive route for the fabrication of catalysts for important industrial applications on a large scale. 相似文献
99.
Anatoly N. Trukhin Janis L. JansonsTatyana I. Dyuzheva Ludmila M. LityaginaNikolai A. Bendeliani 《Solid State Communications》2003,127(6):415-418
Luminescence of very small samples of single crystals of coesite and stishovite has been studied. The spectra were detected under ionizing radiation (X-ray and electron beam) and the decay kinetics of cathodoluminescence in the range of time from 10 ns to 3 ms was measured. The coesite luminescence possesses a broad band at 3 eV with exponential decay about 680 μs at 80 K. The nature of this luminescence was explained as a self-trapped exciton creation in tetrahedron framework. The stishovite luminescence possesses two bands—blue (2.8 eV) and UV (4.7 eV). The UV band intensity grows more than 20 times with irradiation dose from initial level. This shows that the corresponding luminescence centers could be induced by the radiation. The decay of the UV band possesses a fast and a slow component. The determination of the fast decay parameters is beyond the capabilities of our apparatus (less than 10 ns), whereas the slow decay of the UV is non-exponential and takes place in the range of hundreds of microsecond. The blue band decay kinetics can be well approximated by power law ∼t−2, which may correspond to recombination of defects created by radiation. The stishovite single crystal luminescence is very similar to that of germanium dioxide single crystal of rutile structure. The nature of the stishovite luminescence is explained as recombination of defects created by irradiation in octahedron-structured lattice. 相似文献
100.
A two-dimensional non-isothermal stationary mathematical model of the catalytic membrane reactor for the process of methanol dehydrogenation is described. Copper supported on the carbonaceous support was considered as a catalyst. The reaction of methanol dehydrogenation was thermodynamically conjugated with a reaction of hydrogen oxidation taking place in a shell side of the membrane reactor. The effects of various parameters on the methanol conversion and the methyl formate yield have been calculated with the developed model and discussed. Two different types of heating the gas flow were considered and compared. In the case of conjugated dehydrogenation process, the methyl formate yield reaches 77%, when the reactor outer wall was heated up to 150 °C. When the inlet gas flows in the tube and shell sides were heated up to 100 and 83 °C, correspondingly, the yield was 72%. 相似文献