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1.
2.
The interaction of the clathrate Pt6Cl12 · 0.1 EtCl · 5.7H2O with RCN nitriles results in cis-[Pt(PhCH2CN)2Cl2] and in [Pt(RCN)2Cl2] (R = CH2CO2Et, Ph) complexes as a mixture of cis- and trans-isomers which separated and characterized. Cis-[Pt(MeCN)2Cl2] has been synthesized using a well known technique of K2[PtCl4] interaction with acetonitrile in water. Heating cis-[Pt(RCN)2Cl2] (R = Me, CH2Ph, CH2CO2Et) in the solid phase leads to cis-trans isomerization. In case of cis-[Pt(PhCN)2Cl2] thermal conversion results in trans-[Pt(PhCN)2Cl2] but the process of geometrical isomerizations accompained by a considerable decomposition of starting material and/or final products. Boiling of cis-[Pt(PhCH2CN2)Cl2] in mixture of EtNO2? PhCH2CN or cis-[Pt(EtCO2CH2CN)2Cl2] in MeNO2 or EtNO2 solutions results in complete cis-trans conversion. Similarily heating of cis-[Pt(RCN)2Cl2] (R = Me, Ph) in solution produces an equilibrium mixture of cis- and transisomers. 相似文献
3.
A. V. Turov S. P. Bondarenko A. A. Tkachuk V. P. Khilya 《Russian Journal of Organic Chemistry》2005,41(1):47-53
Various lanthanide shift reagents Ln(fod)3 were found to affect the conformational composition of 2-methoxychalcones. Coordination of Yb(fod)3 occurs mainly at the carbonyl oxygen atom of the substrate, while Eu(fod)3 and shift reagents derived from other lanthanides coordinate substituted chalcones as bidentate ligands, giving rise to a secondary tetrachelate with the corresponding change of conformation of the substrate molecule. The possibility for chelation is determined by steric hindrances in the vicinity of the substrate coordination centers and concurrent coordination of other electron-donor groups present in the substrate molecule.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 51–56.Original Russian Text Copyright © 2005 by Turov, Bondarenko, Tkachuk, Khilya. 相似文献
4.
The rare-earth intermetallic compounds (RE)12Co5Bi (RE = Y, Gd, Tb, Dy, Ho, Er, Tm) were prepared by arc-melting and annealing at 600 degrees C. These compounds extend the previously known (RE)6M2+xX1-x (M = Co, Ni; X = Ga, In, Sn, Pb) series with the Ho6Co2Ga-type structure to X = Bi. The crystal structure of Ho12Co5Bi was refined by the Rietveld method from powder X-ray diffraction data obtained using synchrotron radiation (Pearson symbol oI36, orthorhombic, space group Immm, Z = 2, a = 9.37598(14) A, b = 9.37871(14) A, c = 9.85465(13) A). Unlike other Ho6Co2Ga-type compounds, the 2a site in Ho12Co5Bi is exclusively occupied by Co atoms. Four-probe electrical resistivity measurements on sintered polycrystalline samples of (RE)12Co5Bi indicated metallic behavior. Magnetic measurements revealed behavior ranging from frequency-dependent maxima in the ac susceptibility for Y12Co5Bi to possible ferrimagnetic ordering for Gd12Co5Bi to antiferromagnetic ordering with metamagnetic transitions for the remaining compounds. As confirmed by band structure calculations using Y12Co5Bi as a model compound, Y-Y and Y-Co interactions are the most important bonding components, but matrix effects are likely responsible for anomalously short Co-Co contacts in the structure. 相似文献
5.
N. V. Gorbulenko T. M. Tkachuk T. V. Shokol V. V. Semeniuchenko A. V. Turov V. P. Khilya 《Chemistry of Heterocyclic Compounds》2007,43(5):569-575
The interaction has been studied of a series of substituted 3-hetaryl-7-hydroxychromones with amino acids and formaldehyde
(reactants ratio 1: 1: 2 respectively). In the case of glycine and Het = 3-isoxazolyl the product of aminomethylation at position
8 of the chromone was obtained, and with other Het (including Het = 4-phenyl-1,2,4-triazol-3-yl) 2-[6-alkyl-3-hetaryl-4-oxo-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]-oxazin-9-yl]acetic
acids were formed. With β-alanine and Het = 4-phenyl-1,2,4-triazol-3-yl the corresponding β-substituted propionic acid was
synthesized, but proline did not participate in the reaction, leading to bis(6-ethyl-3-hetaryl-7-hydroxychromon-8-yl)methane.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 683–689, May, 2007. 相似文献
6.
Andriy V. Tkachuk 《Journal of solid state chemistry》2004,177(11):3939-3943
The isostructural ternary transition-metal silicides Zr3Mn4Si6 and Hf3Mn4Si6 can be prepared by direct reaction of the elemental components or by arc-melting. The single-crystal structure of Zr3Mn4Si6 was determined by X-ray diffraction (Pearson symbol tP104, tetragonal, space group P42/mbc, Z=8, , ). Zr3Mn4Si6 is isostructural to Nb3Fe3CrSi6 and contains an essentially ordered arrangement of the transition-metal atoms. Square antiprismatic clusters with Zr and Mn atoms at the corners and Si atoms at the center share opposite faces to form one-dimensional columns extending along the c direction. These columns occupy channels that are outlined by a framework of edge- and face-sharing MnSi6 octahedra. The extensive metal-metal interactions in the structure are complemented by Si-Si bonding in the form of dumbbells, linear chains, and zigzag chains. 相似文献
7.
V. I. Minkin A. V. Tkachuk M. E. Kletskii D. V. Steglenko V. A. Voronina S. V. Kurbatov 《Russian Chemical Bulletin》2013,62(2):464-470
Neutral aromatic electrophiles, such as trinitrobenzene and dinitrobenzofuroxane, covalently bound to the furotroponimine moiety form intramolecular through-space charge-transfer π-complexes both in solution and in the crystalline state. The kinetic and activation parameters of stereodynamic processes were determined by dynamic NMR spectroscopy. These parameters provide quantitative estimates of the kinetic stability of the p-complexes. The electronic and geometric characteristics of the π-complexes were calculated by the B3LYP/6-31G** method. 相似文献
8.
L. L. Gur’eva A. I. Tkachuk L. I. Kuzub G. A. Estrina E. I. Knerel’man I. I. Khodos B. A. Rozenberg 《Polymer Science Series B》2013,55(3-4):139-146
Silver nanoparticles stabilized by polystyrylmonocaboxylate ligands with varied chain lengths are synthesized via the low-temperature reduction of silver polystyrylmonocaboxylate with triethylamine. Silver nanoparticles have small dimensions, narrow size distributions, high stability, and ability to redisperse in nonpolar solvents. The kinetic features of the reaction are studied via high-performance liquid chromatography; UV, visible and IR spectroscopy; and transmission electron microscopy. It is shown that the reduction of silver occurs in the cores of reverse micelle species organized by diphilic macromolecules of silver polystyrylmonocarboxylates. 相似文献
9.
N. N. Panina T. A. Grebeneva Ya. M. Gurevich A. I. Tkachuk M. A. Kim 《Polymer Science Series D》2014,7(2):105-111
The influence of epoxy imide cycloaliphatic epoxy resin EPOX-01 on the rheological properties of the epoxy amine system was investigated. The effect of the amount of amine hardener for solidification process of modified system is evaluated. It is shown that the use of epoxy imide cycloaliphatic resin allows one to obtain materials with improved technological characteristics of film technology (RFI). 相似文献
10.
G. B. Tkachuk 《Journal of Applied Spectroscopy》1965,3(1):14-18
The diffusion of resonance radiation in a gas-filled volume has been studied by the luminescent probe method. The resulting data are compared with theory.In conclusion, I express my sincere appreciation to V. A. Fabrikant, who supervised the present study, and to L. M. Biberman and F. A. Butaeva for assisting in its execution. 相似文献