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1.
2.
V. B. Sokolov A. N. Chekhlov T. A. Epishina I. V. Martynov 《Russian Chemical Bulletin》1992,41(2):236-240
The O-(arylcarbamoyl)butyrhydroximoyl chlorides were synthesized, and the x-ray structural analysis (XSA) of one of them — O-(o-tolylcarbamoyl)butyrhydroximoyl chloride — was performed. It was established from the data of the XSA and the PMR spectra that all synthesized compounds are the Z isomers.Institute of Physiologically Active Substances, Russian Academy of Sciences, 142432 Chernogolovka. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 315–319, February, 1992. 相似文献
3.
A. V. Vypirailenko I. B. Dzvinchuk M. O. Lozinskii 《Chemistry of Heterocyclic Compounds》2003,39(1):123-125
2-Phenacylbenzothiazole reacts with hydrazines and o-hydroxybenzaldehydes to give hydrazones and chalcones. These compounds tend to isomerize to benzothiazole-2-spiro-3'-pyrazoles and benzo[b]pyran-2-spiro-2'-benzothiazoles, respectively. 相似文献
4.
M. G. Ezernitskaya B. V. Lokshin T. Yu. Orlova V. N. Setkina V. I. Shilnikov S. Nunziante Cesaro 《Russian Chemical Bulletin》1994,43(11):1841-1845
FTIR spectra have been studied for staircase cyclopentadienyl complexes containing two or three metal carbonyl fragments bound by the metal-carbon bond Cp(CO)2Fe-CpmMn(CO)3 (1), Cp(CO)2Fe-CpmFe(CO)2CH2Ph (2), Cp(CO)2Fe-Cpm(CO)2Fe-CpmMn(CO)3 (3), Cp(CO)2Mo-Cpm(CO)2Fe-CpmMn(CO)3 (4), Cp(CO)3W-Cpm(CO)2Fe-CpmMn(CO)3 (5), Cp(CO)2Fe-Cpm(CO)2Fe-BmCr(CO)3 (6), Cr(CO)3Bm-CpmFe(CO)2CH2Ph (7), where Cp = 5-C5H5, Cpm = 15-C5H4, Bm = 16-C6H5. Temperature-dependent FTIR spectra were measured inn-pentane solutions over a wide temperature range and in the low-temperature solid matrices of argon and nitrogen. Rotamers, formed due to rotation about the metal-carbon -bond, were found in solutions and matrices. A molecular mechanics calculation of1 proved the possibility of such rotation.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1952–1956, November, 1994.The authors are grateful to the Russian Foundation for Basic Research (project code No 93-03-18592) and to the International Science Foundation (project code No MEQ000). 相似文献
5.
Omar Deeb Prof. Monika Leibscher Dr. Jörn Manz Prof. Wulf von Muellern Tamar Seideman Prof. 《Chemphyschem》2007,8(2):322-328
We propose an approach for separating nuclear spin isomers with coherent light and illustrate it by numerical calculations using fulvene as a model system. The scheme employs the equivalence of torsion and interchange of equivalent H-atoms in a class of molecules of which fulvene is a simple example. The exchange symmetry couples with the rotational symmetry to produce a spatial distinction between the two photo-excited nuclear spin isomers, and wavepacket interferometry is applied to separate the species. 相似文献
6.
用 CNDO/2方法在 586微机上计算了 C57X3C56X4(X=B、N、P)的 234个位置异构体的电子结构。在C57X3(X=B、N、P)位置异构体中,C57X3(1,2,9)(X=B、N、P)分别是最稳定的。对于C56X4(X=B、N、P)位置异构体,C56B4(1,2,9,8),C56N4(1,2,9,12)和C56P4(1,2,9,12)分别是最稳定的,但稳定性都比C60差。其氧化或还原性都比 C60好,将它们和 C60比较,与 X相距一个或两个键的 C原子电荷密度增加或减少较多,其余电或亲核反应性增加;X与 X,X与 C原子之间 Wiberg Order都减少较多,其键的强度削弱;邻近杂原子的 C与 C原子之间 Wiberg Order减少或增加很少,其键的强度稍有削弱或增强。 相似文献
7.
A new compound (5R, 10R)-3,8-dihydroxy-5,10-diethoxy-5,10-dihydrochromeno[5,4,3-cde]chromene monohydrate was obtained from 3,4-dihydroxybenzaldehyde in aerobic basic aqueous ethanol solution in the presence
of manganese chloride and triethylamine and crystallized in orthorhombic P212121 space group (denoted as 1). When 1 was recrystallized from aqueous methanol, it was transformed to another crystal (2) with the same composition but in P21/n space group. The drastic difference in the extensive hydrogen bond network makes 1 a 3D and 2 a 2D infinite supramolecular structure, respectively. 相似文献
8.
A. V. Virovets S. N. Konchenko P. S. Yuferov D. Fenske 《Journal of Structural Chemistry》2004,45(3):496-501
The crystal structures of three cluster compounds: [(µ-H)Fe2Mo(µ3-Te)(CO)8Cp*], [FeMo2(µ3-Te)(CO)7x Cp*2], and [FeMoW(µ3-Te)(CO)7CpCp*], where Cp = 5-C5H5, Cp* = 5-C5 (CH3)5, have been investigated. In the cluster with a tetrahedral {FeMo2Te} core, one can observe positional isomerism of the carbonyl and cyclopentadienyl ligands with respect to the plane through the Fe and Te atoms and the center of the Mo2bond, resulting in two mirror isomers in the racemic crystal. In the cluster with the {FeMoWTe} core, additional chirality causes the formation of four diastereoisomers. Earlier, the structure of the [FeMoW(µ3-Se)(CO)7Cp] cluster with Mo and W atoms coordinated to identical Cp-ligands has been structurally defined. In this crystal, statistical disordering of Mo and W over the metal positions is observed. In the [FeMo(Cp*)W(Cp)(µ3-Te)(CO)7] cluster studied here, the Mo and W atoms are coordinated to different cyclopentadienyl ligands. Due to this, two of four diastereoisomers were isolated as ordered racemic crystals; the other two are nonexistent for steric reasons.Original Russian Text Copyright © 2004 by A. V. Virovets, S. N. Konchenko, P. S. Yuferov, and D. FenskeTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 522–527, May–June 2004. 相似文献
9.
S. V. Fedorov A. Yu. Rulev N. N. Chipanina A. M. Shulunova V. G. Nenajdenko E. S. Balenkova D. A. Tyurin V. K. Turchaninov 《Russian Chemical Bulletin》2005,54(1):103-107
The molecular structures of β-amino-α-bromovinyl trifluoromethyl ketones was studied by UV, IR, 1H, 13C, and 15N NMR spectroscopy and using the density functional (B3LYP/6-31G(d,p) and PBE/QZ3P) and ab initio riMP2/cc-pVTZm quantum-chemical calculations. Factors affecting stabilization of the EZE-conformation of the molecules, which is atypical of analogous unsubstituted amino enones, are considered.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 102–106, January, 2005. 相似文献
10.
Hiroshi Kojima Kosaku Sakeda Teijiro Ichimura Masao Takayanagi 《Journal of Molecular Structure》2003,655(1):185-190
Laser-induced fluorescence (LIF) excitation spectra of m-methylanisole in a supersonic jet were measured. Two series of progressions were observed in the spectrum, originating at 36048 and 36115 cm−1, which were successfully assigned to the transitions to the methyl internal rotational vibronic levels of the two isomers, i.e. cis and trans isomers, with the aid of hole-burning spectrum measurements and quantum-chemical calculations. The progression for the trans isomer was observed up to the 6a1 band, while only the 3a1 band in addition to the 0a1 and 1e bands was observed for the cis isomer. This finding can be explained by the conformational change upon the electronic excitation; the 60° rotation of the methyl torsional angle takes place for the trans isomer but not for the cis isomer. 相似文献