排序方式: 共有15条查询结果,搜索用时 31 毫秒
1.
Shahkel'dyan I. V. Melekhina E. K. Atroshchenko Yu. M. Efremov Yu. A. Alifanova E. N. Kopyshev M. V. Troitskii N. A. Subbotin V. A. Nikishina M. B. 《Russian Journal of Organic Chemistry》2003,39(4):589-595
A series of 7-carboxy-3-R-1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes was synthesized by reduction of 3,5-dinitrobenzoic acid with sodium borohydride followed by Mannich reaction with formaldehyde and primary amines. The mechanism of decomposition under electron impact of the 3-azabicyclo[3.3.1]nonane was established. Enthalpies of formation of compounds synthesized were calculated by semiempirical PM3 method. 相似文献
2.
A versatile synthesis of novel oligothiophene-nucleoside conjugates based on Cu(I)-catalyzed alkyne-azide cycloaddition ("click-reaction") has been developed. Complementary thymidine- and adenosine-functionalized quaterthiophenes form recognition-driven superstructures via hydrogen bonding and other competing intermolecular forces. Self-aggregated fibers up to 30 microm in length were characterized with atomic force microscopy. 相似文献
3.
Santer S Kopyshev A Donges J Rühe J Jiang X Zhao B Müller M 《Langmuir : the ACS journal of surfaces and colloids》2007,23(1):279-285
The correlation between the morphology of mixed polymer brushes and fluctuations of the grafting points is investigated by single-chain-in-mean-field simulations and experiments. The local topography of two types of mixed polystyrene-polymethylmethacrylate (PS-PMMA) brushes that differ in their modes of attachment has been studied during repeated microphase separation into laterally structured and homogeneous morphologies upon changing solvents. In the first type of brush (conventional), each of the surface-attached initiator groups starts the growth of either a PS or a PMMA chain in a random fashion. In the second case (Y-shaped mixed brushes), two chains of different types are attached to the same anchor group on the substrate. Whereas in the first case statistical fluctuations of the chemical composition occur on a local scale, such composition fluctuations are strongly suppressed in the latter case. The microphase-separated morphology is similar in both cases, but Y-shaped brushes exhibit a significantly weaker domain memory than do conventional PS-PMMA mixed brushes. The results of the experiment are compared with simulations, and a simple phenomenological argument and qualitative agreement are found. The observations demonstrate that small fluctuations in the grafting points are amplified by the microphase separation and nucleate the location of the domains in the mixed brush. 相似文献
4.
Emmanuelle Schué Alexey Kopyshev Jean-François Lutz Hans G. Börner 《Journal of polymer science. Part A, Polymer chemistry》2020,58(1):154-162
A synthesis route to controlled and dynamic single polymer chain folding is reported. Sequence-controlled macromolecules containing precisely located selenol moieties within a polymer chain are synthesized. Oxidation of selenol functionalities lead to diselenide bridges and induces controlled intramolecular crosslinking to generate single chain collapse. The cyclization process is successfully characterized by SEC as well as by 1H NMR and 2D HSQC NMR spectroscopies. In order to gain insight on the molecular level to reveal the degree of structural control, the folded polymers are transformed into folded molecular brushes that are known to be visualizable as single molecule structures by AFM. The “grafting onto” approach is performed by using triazolinedione−diene reaction to graft the side chain polymers. A series of folded molecular brushes as well as the corresponding linear controls are synthesized. AFM visualization is proving the cyclization of the folded backbone by showing globular objects, where non-folded brushes show typical worm-like structures. © 2019 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 154–162 相似文献
5.
I. E. Yakunina A. N. Shchukin M. V. Kopyshev I. V. Shakhkel’dyan A. N. Shumskii A. A. Yakovenko K. A. Lysenko Yu. M. Atroshchenko 《Russian Journal of Organic Chemistry》2011,47(6):877-880
Reduction of 6-substituted 1,5-dinitro-3-azabicyclo[3.3.1]non-6-enes gives either saturated 1,5-diamino-3-azabicyclo[3.3.1]nonane
or unsaturated 1,5-diamino-3-azabicyclo[3.3.1]non-6-enes, depending on the conditions and nature of substituent in the substrate. 相似文献
6.
Shakhkeldyan I. V. Melekhina N. K. Atroshenko Yu. M. Kopyshev M. V. Borbulevich O. Ya. Suponitskii K. Yu. Antipin M. Yu. Alifanova E. N. Nikisina M. B. Subbotin V. A. 《Russian Journal of Organic Chemistry》2004,40(2):247-254
N-Alkylation of 6(7)-R-1,5-dinitro-3-methyl-3-azabicyclo[3.3.1]non-6-enes with methyl iodide afforded a series of quaternary ammonium salts whose yield depended on the solvent polarity and character of substituents located in positions 6 or 7 of substrate. The presence of electron-withdrawing groups reduced the yield of the target products compared to unsubstituted compound, whereas the electron-donor substituents increased the yield. As shown by the X-ray diffractionstudy the congormation of the substances was not changed in the course of quaternization. The DTA-TG analysis revealed that in the first stage of thermolysis the 6(7)-R-3,3-dimethyl-1,5-dinitro-3-azoniabicyclo[3.3.1]non-6-ene iodides suffer dealkylation. Two fragmentation paths of compounds synthesized under electron impact were observed: elimination either of methyl iodide or aziridinium cation. 相似文献
7.
Kopyshev M. V. Shakhkeldyan I. V. Kozlova L. M. Litvin E. F. Sharf V. Z. Troitskii N. A. Atroshchenko Yu. M. Alifanova E. N. Nikishina M. B. Vorontsov I. N. Gurylev D. V. 《Russian Journal of Organic Chemistry》2004,40(2):255-260
During catalytic reduction with hydrogen on nickel of a series of 3-substituted 1,5-dinitro-3-azabicyclo-[3.3.1]non-6-enes alongside nitro groups reduction occurred also hydrogenation of the double bond. New diamines of the 3-azabicyclo[3.3.1]nonane series were synthesized, and their structure was established by means of IR, 1H and 13C NMR spectroscopy and X-ray diffraction study. 相似文献
8.
9.
V. P. Kopyshev 《Journal of Applied Mechanics and Technical Physics》1971,12(1):103-107
In this paper we derive an approximate equation of state of a dense fluid in which the thermal pressure is completely determined by the pressure dependence of the volume at 0 ° K. We also consider some generalizations (which take into account the attractive forces of the atoms and the presence of mixtures).Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 1, pp. 119–122, January–February, 1971. 相似文献
10.
Santer S Kopyshev A Donges J Yang HK Rühe J 《Langmuir : the ACS journal of surfaces and colloids》2006,22(10):4660-4667
The nano-phase-separation in mixed polymer brushes consisting of polystyrene and poly(methyl methacrylate) (PS-PMMA) chains attached to a silicon surface is studied. The topographies of the mixed brushes are examined after they have been exposed to solvents which induce or erase nano-phase-separation. It is discussed whether the brush locally forms the same pattern every time the transition from the smooth and featureless to the nanopatterned state occurs ("domain memory") or if the local assembly of the domains emerges in a different arrangement after each cycle of topography switching. A memory measure parameter is introduced, which characterizes quantitatively the domain memory effect in the nanopattern. It is shown that at constant grafting density but with increasing molecular weight of the brush chains the memory measure parameter decreases. In contrast to this, brushes with constant molecular weight, but differing in grafting density, all have a similar domain memory. We discuss a possible origin of the domain memory effect in the mixed brush systems studied and point out its impact on the motion of nanoparticles adsorbed on top of such systems. 相似文献