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131.
Oleg G. Sinyashin Irina P. Romanova Gulshat G. Yusupova Valery I. Kovalenko Yuri Y. Efremov Irina I. Vandyukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract Data on the structure of cycloadducts of organophosphorus dipolar reagents and fullerenes arc absent, to our knowledge. We died the reactions and the shucturc of cycloadducts of phosphorylated azidcs and nitrile oxide with [60]fullcrcnc. The cycloaddition of diphcnylphosphinic llzide to fullcrme has bcm determined to lead to the 1 -[(N-diphenylphosphoryl)amino]-2-hydroxy[6O]hllcrme (l), the mixhuc of phosphorylated aziridinofullcrcne (2) and derivative of fullerne (3) with one aziridine fragment and one aminohydmxy-fragment, or to product (4), depending on the conditions of don . 相似文献
132.
Lidiya I. Kursheva Olga N. Kataeva Dmitrii B. Krivolapov Elvira S. Batyeva Oleg G. Sinyashin 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1425-1426
Abstract The synthesis and coordination chemistry of ligands bearing PS donor groups in complexes with copper(I) halides, in particular thiophosphites, thiophosphonites, and thiophosphinites, are described. 相似文献
133.
Nimmy R. Mammoottil James F. Reuther Dumindika A. Siriwardane Oleg V. Kulikov Bruce M. Novak 《Journal of polymer science. Part A, Polymer chemistry》2017,55(18):2915-2934
Described herein is a comprehensive survey on the most recent advancements in polycarbodiimide synthetic methodologies, structure determination, property design, and self-assembly. In particular, the 15N-isotopic enrichment of polycarbodiimides is detailed along with the use of 15N NMR to identify the regioregularity and mechanism of chiroptical switching in polycarbodiimides. Furthermore, the new Ni(II) mediated “living” polymerization is explained along with its utilization in the incorporation of polycarbodiimides into block copolymers, graft copolymers, and star polymers. Finally, we review the recent discoveries focusing on the highly tunable self-assembly behaviors of polycarbodiimide homopolymers and copolymers. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2915–2934 相似文献
134.
Oleg V. Yazyev 《Solid State Communications》2012,152(15):1431-1436
Recent experimental investigations show that large-area samples of graphene tend to be polycrystalline. Physical properties of such samples are strongly affected by the presence of intrinsic topological defects of polycrystalline materials—dislocations and grain boundaries. This article reviews recent progress in understanding dislocations and grain boundaries in graphene. First, a systematic approach towards constructing topological defects in graphene is introduced. Then, the review discusses the formation energies of these defects, stressing the dramatic stabilization of dislocations and small-angle grain boundaries in graphene due to the two-dimensional nature of this material. Finally, the electronic transport properties of polycrystalline graphene are considered, showing that topological defects may present novel opportunities towards engineering electronic devices based on graphene. 相似文献
135.
Oleg M. Demchuk I. Justyniak B. Miroslaw R. Jasinski 《Journal of Physical Organic Chemistry》2014,27(1):66-73
Because of their unique visual optic and electronic properties, substituted quinones are commonly used as dyes and pigments; nevertheless, a theoretic background of relationship between the structures and optical properties of such compounds seems to be still undeveloped. Two crystalline forms of 2‐methoxynaphth‐1‐yl‐naphthoquinone (MNQ) have been synthesized and characterized by means X‐ray, NMR, UV–VIS, as well as, MS spectroscopy. The interpretation of intriguing optical properties of two crystalline forms of MNQ, based on detailed spectral and structural characterization, as well as, DFT and MP2 computations clearly connects the conformation of the molecules with their optical and electronic properties. Thus, flatter conformation, stabilized by crystal net force, favours the intense electron density transition from auxochrome to chromophore moiety (which corresponds excitation from HOMO to LUMO), as well as, favours the π‐stacking interaction, that eventually results in colour enhancement. At the same time, small molecules of solvents included into the crystal net allow molecules of arylnaphthoquinones to adopt less rigid conformation what has a dramatic optical outcome. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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138.
Yana I. Sakhno Svetlana V. Shishkina Oleg V. Shishkin Vladimir I. Musatov Elena V. Vashchenko Sergey M. Desenko Valentin A. Chebanov 《Molecular diversity》2010,14(3):523-531
Heterocyclization reactions of pyruvic acids, aromatic aldehydes and 5-amino-N-aryl-1H-pyrazole-4-carboxamides yielding four different types of final compounds are described. The reactions involving arylidenpyruvic
acids lead with high degree of selectivity to either 4,7-dihydropyrazolo[1,5-a]pyrimidine-5-carboxylic acids or 5-[(2-oxo-2,5-dihydrofuran-3-yl)amino]-1H-pyrazoles, depending on the catalyst type or temperature regime. The interactions based on arylpyruvic acids can take place
under kinetic or thermodynamic control producing 7-hydroxy-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidine-7-carboxylic acids or 3-hydroxy-1-(1H-pyrazol-5-yl)-1,5-dihydro-2H-pyrrol-2-ones, respectively. 相似文献
139.
140.
Evgenyi V. Gryshkun Natalia V. Andrushko Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1027-1046
Racemic chlorophosphines react stereoselectively with chiral l-phenylethylamines or amino acid esters to give diastereomerically enriched aminophosphines 3, which were isolated as diastereomerically pure crystalline borane complexes. Oxidation, thionation, the reaction with methyl iodide provide optically active derivatives of aminophosphines. (R,S)- and (S,S)-stereomers of phosphinic acid amides were separated by crystallization and a flash-chromatography. The stereochemical properties of phosphorus acid amides were investigated. The mechanism of asymmetric induction at the trivalent phosphorus atom was rationalized. 相似文献