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31.
32.
Three novel supramolecular arrays of zigzag polyaromatic salts are reported. Both the conformation and disposition of the dications are subjected to various noncovalent interactions. Thus, the presence or absence of the π‐π interacting enclathrated molecules, the efficient packing and the involved hydrogen bonding interactions of anions, as well as the increased hydrophobic property of the dications themselves exert influence. 相似文献
33.
Sevim Akyüz Tanil Akyüz J. Eric D. Davies 《Journal of inclusion phenomena and macrocyclic chemistry》1993,15(2):105-119
The adsorption of 4,4-bipyridyl by natural sepiolite and smectite group clay minerals (bentonite, hectorite and saponite) from Anatolia (Turkey) has been studied using vibrational spectroscopy. Investigation of Fourier-transform infrared and Fourier-transform Raman spectra of adsorbed 4,4-bipyridyl indicate the presence of chemisorbed species. However, any evidence for the generation of anionic species on the surface of the phyllosilicates has not been detected. It is proposed that the adsorbed bipyridyl molecules on sepiolite are centrosymmetric and H-bonded to the surface hydroxyls through both the nitrogen lone pairs as bidentate ligands. The adsorbed bipyridyl molecules on the smectite group clays are coordinated to exchangeable cations both directly and also indirectly through water as monodentate ligands. XRD patterns of the clays studied are also recorded. 相似文献
34.
I. I. Ponomarev Yu. Yu. Rybkin E. I. Goryunov P. V. Petrovskii K. A. Lyssenko 《Russian Chemical Bulletin》2004,53(12):2881-2883
The reaction of 4,4-dimethyldiphenyl ether with phosphorus trichloride in the presence of anhydrous aluminum chloride was studied. This reaction affords 2,8-dimethyl-10H-105-phenoxaphosphine 10-oxide as virtually the only product. In air, the latter in an alkaline solution is quantitatively transformed into 10-hydroxy-2,8-dimethyl-10H-105-phenoxaphosphine 10-oxide.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2762–2765, December, 2004. 相似文献
35.
Yu. G. Budnikova A. G. Kafiyatullina Yu. M. Kargin O. G. Sinyashin 《Russian Chemical Bulletin》2003,52(7):1504-1511
Electrochemical reduction of cobalt(ii) complexes containing -acceptor ligands (L = bpy, Ph2Ppy) proceeds through three consecutive reversible steps: one-electron transfer to form a more stable CoIL complex, transfer of two electrons at more negative potentials to form an anionic [NiL]– complex, and reduction of the ligand to the radical anion. The stability of the cobalt complexes with different ligands decreases in the series Ph2Ppy > Ph3P > bpy. 相似文献
36.
B. S. Fedorov N. I. Golovina L. S. Barinova V. V. Arakcheeva G. V. Lagodzinskaya M. V. Loginova R. F. Trofimova V. Z. Laishev V. F. Lazarev S. P. Smirnov I. Sh. Abdrakhmanov A. I. Firkin L. O. Atovmyan 《Russian Chemical Bulletin》1992,41(12):2185-2188
1,1,4,4-Tetranitrobutane-2,3-diol reacts with formaldehyde, forming 2,2-dinitropropane-1,3-diol or a cyclic ether — 4,4-dinitro-2,3-dihydroxytetrahydrofuran — as a function of the reaction conditions.Institute of Chemical Physics, Chernogolovka, Russian Academy of Sciences, 142432 Chernogolovka. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2755–2759, December, 1992. 相似文献
37.
All the investigated reactions of 5-cyano-1,4,6,9-trioxathia-5-phosphaspiro[4,4]nonanes with compounds containing a labile hydrogen atom proceed with the loss of HCN, predominant opening of the oxathiophospholane ring, and formation of 2-oxo-1,3,2-dioxaphospholane derivatives.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, p. 2670–2673, November, 1992. 相似文献
38.
Ji‐Jiang Wang Meng‐Lin Yang Huai‐Ming Hu Prof. Dr. Gang‐Lin Xue Dong‐Sheng Li Qi‐Zhen Shi 《无机化学与普通化学杂志》2007,633(2):341-345
To determine the influence of the size of the aromatic chelate ligands on the frameworks of metal tretracarboxylate polymers, two new coordination polymers [Cd(btc)0.5 (2,2′‐bpy)] ( 1 ) and [Cd(btc)0.5(phen)]·H2O ( 2 ) (H4btc = biphenyl‐3,3′,4,4′‐tetracarboxylic acid, 2,2′‐bpy = 2,2′‐bipyridine, phen = 1,10‐phenanthroline) have been synthesized under similar hydrothermal conditions. In complex 1 , the dimeric Cd2 units are linked by bridging btc4? ligand to form a 2D layered network, whereas complex 2 possesses a 3D metal‐organic framework consisting of the dimeric Cd2 units. The differences of two metal‐organic frameworks demonstrate that the size of the rigid aromatic chelate ligands have an important effect on the structures of their complexes. Additionally, the two complexes show strong fluorescence in the solid state at room temperature. 相似文献
39.
4,4-Difluoro-5-trifluoromethyl-2-(2,2,2-trifluoro-1-trifluoromethylethyl)-4H-1,3-dioxine andcis/trans-3-dimethylamino-2-trifluoromethacryloyl fluoride were obtained by reaction ofN-(3,3,3-trifluoro-2-trifluoromethylprop-1-enyl)dimethylamine with MgSO4·7H2O.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1069–1071, May, 1997. 相似文献
40.
Zheng-Zhong Lin Rui-hu Wang Lei Han Rong Cao 《Journal of solid state chemistry》2004,177(7):2494-2498
The indium(III)-organic compound [In(HBtc)2(4,4′-bpy)](4,4′-Hbpy)(H2O)0.5 (Btc=1,3,5-benzenetricarboxylate, 4,4′-bpy=4,4′-bipyridine) has been synthesized under hydrothermal condition and characterized by IR, fluorescent spectroscopy, TGA and single-crystal X-ray diffraction analyses. The compound crystallizes in monoclinic, space group P2(1)/c, a=17.0884(2) Å, b=12.28390(10) Å, c=17.9456(4) Å, β=104.1920(10)°, V=3652.03(10) Å3, Z=4, R1=0.0572 and wR2=0.1116 [I>2σ(I)]. All the indium atoms in the compound are hepta-coordinated and link 1,3,5-benzenetricarboxylate forming a 2-D layer structure with rhombus grids. 相似文献