共查询到20条相似文献,搜索用时 469 毫秒
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Yurij A. Simonov Alexander A. Dvorkin Marina S. Fonar Edward V. Ganin Sergei A. Kotlyar 《Journal of inclusion phenomena and macrocyclic chemistry》1991,11(1):1-14
The title compounds were prepared by treating a methanol solution of the corresponding crown ether with an aqueous solution of aminosulfuric acid.Crystals of [benzo-18-crown-6·H2NSO2OH] suitable for X-ray crystallography were obtained by recrystallization from methanol. The crystals are orthorhombic, space groupP212121,a = 14.310(7),b = 12.516(4),c = 10.890(4) Å. Refinement led to a final conventionalR value of 0.051 for 909 reflections.Crystals of [18-crown-6·H2NSO2OH] suitable for X-ray crystallography were obtained by recrystallization from acetone. They are orthorhombic, space groupP212121,a = 17.027(6),b = 14.866(5),c = 8.345(4) Å. The structure was solved by a heavy atom method and refined to an agreement value of 0.067. 相似文献
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E. V. Guseva T. E. Busygina R. A. Khasanshin V. K. Polovnyak E. G. Yarkova R. A. Yusupov 《Russian Journal of General Chemistry》2004,74(10):1478-1484
Compounds of the compositions [2(18-crown-6)6(H2O)2(C2H4Cl2){Pt2+(C2H4)}(Pt2Cl10)2–], [4(18-crown-6)2(OH3)+2(OH2)2(NH3)(Pt2Cl10)2–], [(dibenzo-18-crown-6)6(H2O){Pt2+(C2H4)}(Pt2Cl10)2–], and [4(dibenzo-18-crown-6)2(OH3)+2(OH2)2(NH3)Pt2Cl10)2–] were prepared by reactions of H2PtCl6 with 18-crown-6 and dibenzo-18-crown-6.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1593–1599.Original Russian Text Copyright © 2004 by Guseva, Busygina, Khasanshin, Polovnyak, Yarkova, Yusupov.This revised version was published online in April 2005 with a corrected cover date. 相似文献
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S. V. Demin V. I. Zhilov A. Yu. Tsivadze V. V. Yakshin O. N. Vilkova N. A. Tsarenko 《Russian Journal of Inorganic Chemistry》2006,51(10):1678-1681
The extraction of rare-earth elements (REE) by alkylated crown ethers (dibenzo-and dicyclohexano-18-crown 6; DB18C6 and DCH18C6) from acid solutions in the chloroform-water system is studied. The extraction of the REE with DCH18C6 and its alkylated derivatives in the presence of trichloroacetic acid (TCA) is far more efficient than the extraction with DB18C6 and its alkylated derivatives or when nitric or acetic acid is used instead of TCA. The distribution coefficients for the cerium metals are far higher than for the yttrium metals. The metal: crown ether ratio in the extracted complex in all cases is 1:1. 相似文献
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A. N. Chekhlov 《Russian Journal of Inorganic Chemistry》2009,54(3):467-471
A new compound, dibenzo-18-crown-6 diaqua(dibenzo-18-crown-6)potassium triiodide [K(Db18C6)(H2O)2)+ · I3− · Db18C6 (I), is synthesized and studied by X-ray crystallography. The crystals of compound I are orthorhombic: a = 22.065 ?, b = 22.140 ?, c = 9.433 ?, Z = 4, space group Pccn. Structure I is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation
to R = 0.098 for all 5974 unique reflections. Structure I contains the following asymmetric units: a half of the I3− centrosymmetric anion and two halves of the mixed equally average [K(Db18C6)(H2O)2]+ host—guest complex cation (a) and a free Db18C6 molecule, each stacked on the axes 2 of the perpendicularly averaged plane
of the eighteen-membered macroheterocycle. In complex I, both Db18C6 molecules (a and b) have a “butterfly” conformation with
approximate symmetry C
2v
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Original Russian Text ? A.N. Chekhlov, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 3, pp. 516–520. 相似文献
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I. Ya. Postovskii I. V. Podgornaya V. A. Popova M. I. Ermakova O. V. Fedorova 《Chemistry of Heterocyclic Compounds》1981,17(11):1076-1080
New derivatives of the macrocyclic polyether dibenzo-18-crown-6 that contain formazyl groupings in the aromatic rings were synthesized. The complexing ability of the polyether ring and the formazyl groupings was studied. Complexes of two types, viz., those that contain a transition metal and those that simultaneously contain a transition metal and an alkali or alkaline earth metal, were isolated in crystalline form.DeceasedTranslated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1479–1483, November, 1981. 相似文献
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H. İBRAHİM UĞRAŞ ÜMİT ÇAKIR AKIN AZİZOĞLU TURGUT KILIÇ ÇAKIL ERK 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(1-2):159-165
Hexadecanoyl, dihexadecanoyl, dioctadecaneoyl, di-10-undecenoyl, and dicis-9-octadecenoyl derivatives of benzo[18]crown-6, dibenzo[18]crown-6 and dibenzo[24]-8 were synthesized by the condensation of carboxylic acids (palmitic, stearic, oleic and undecenoic acid) with benzo and dibenzo crown ethers in the presence of zinc chloride. The extraction equilibrium constants of such macrocyclic ethers with long side chains were estimated using chloroform/water and dichloromethane/water membranes transfer of Na-PAR (4-(2-pyridylazo)-resorcinol mono sodium monohydrate) with UV–Vis spectroscopy. It was found that they were in the range of 10.88–11.71 in dichloromethane and 8.04–11.77 in chloroform. These results actually show that the Na+ binding effect of macrocyclic ethers depends on the type and the length of side chains. The geometrical properties of the molecules were studied employing semi-empirical calculations by simulated annealing technique. The frontier molecular orbital energies and dipole moments were also examined. The biological activity results showed that the synthesized crown ethers have no activity against the studied microorganisms. 相似文献
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Jeffrey C. Bryan Nancy L. Engle Richard A. Sachleben Benjamin P. Hay 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(11):1359-1360
Tribenzo-18-crown-6 binds two acetonitrile ligands, i.e. C24H24O6·2C2H3N, one to each face of the crown ring. The crown conformation is relatively low in energy, but does not appear optimized for cation binding. Few significant intermolecular interactions are observed. 相似文献
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Emanuel Makrlík Petr Vaňura Jan Budka 《Monatshefte für Chemie / Chemical Monthly》2009,287(1):583-585
Abstract
The stability constant of the dibenzo-18-crown-6·H3O+ cationic complex species dissolved in nitrobenzene saturated with water has been determined from extraction experiments in the two-phase water–nitrobenzene system and from γ-activity measurements. Various structures of protonated dibenzo-18-crown-6 are discussed. 相似文献14.
Bis-crown ethers with benzo-15-crown-5 and benzo-18-crown-6 moieties bridged by different length of polyethylene ethers have been successfully synthesized. 相似文献
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The nature of the reaction of a reagent with tetranitrodibenzo-18-crown-6 was found to depend on its basicity. This behavior was interpreted in the framework of the theory of hard and soft acids and bases.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 605–608, May, 1992. 相似文献
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A. N. Chekhlov 《Russian Journal of Coordination Chemistry》2006,32(7):474-480
A complex [Ca(18C6)(H2O)3]2+(ClO 4 ? · 18C6 · H2O is synthesized and studied by X-ray diffraction analysis. The structure (space group P21/n, a = 11.570 Å, b = 16.024 Å, c = 22.225 Å, β = 98.89°, Z = 4) is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.075 for 5305 independent reflections (CAD4 automated diffractometer, λMoK α radiation). In the complex cation of the host-guest type, the Ca2+ cation lies in the cavity of the 18-crown-6 ligand and is coordinated by all the six O atoms and three O atoms of three water molecules. In a crystal, the alternating complex anions, 18C6 molecules, and water molecules are joined by hydrogen bonds into broad infinite chains along the y axis. The disordered ClO 4 ? anions are bonded to these chains on the side through hydrogen bonds. 相似文献
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The coextraction of water with benzo-15-crown-5 (B1SC5), benzo-18-crown-6 (B18C6) and the B18C6-K+ complex into seven low-polar solvents, i.e., carbon tetrachloride (CTC), chloroform (CF), dichloromethane (DCM), 1,2-dichloroethane (1,2-DCE), benzene (BZ), chlorobenzene (CB) and o-dichlorobenzene (o-DCB), has been investigated. The mean hydration number, nH2O, of these solutes in the water-saturated organic solvents was determined. There is a trend that the nH2O values for any solutes increase with increasing the water concentration in the solvents. Those of B18C6 and B15C5 converge at almost 0.8 for B18C6 and 0.4 - 0.5 for B15C5 in the solvents with the relatively high water concentration, i.e., CF, 1,2-DCE, DCM, and nitorobenzene (NB). The nH2O value of B15C5 is about one-half of that of B18C6 for a given organic solvent. The dominant species of the B18C6-K+ complex in these solvents is non-hydrated. From these results, the hydration equilibrium constants, KH2O, in the organic solvents were estimated. 相似文献
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Alexander Y. Nazarenko Oleg I. Kronikovski Marina S. Fonari Victor C. Kravtsov Yury A. Simonov Tadeush J. Malinovski 《Supramolecular chemistry》2013,25(4):259-263
Abstract Solvent extraction of lead halides with 18-crown-6 (18C6), dicyclohexano-18-crown-6 (DC18C6, cis-syn-cis and cis-anti-cis isomers) in chloroform was studied, and the extraction constants corrected for side reactions and ionic strength effects were obtained. The compounds of the same composition as those being extracted were also isolated in crystal form. The molecular structure of the [Pb(18C6)I2] complex has been determined. Crystals are monoclinic, P21/n, a = 11.237(2), b = 10.992(2), c = 8.139(2)Å, β = 97.32(3)°, V = 997.1(7)Å3, Dcalc = 2.416(2)gcm?3, Z = 2 for the composition C12H24O6PbI2. The final R-factor is 0.043 for 558 unique reflections. The lead atom is coordinated to six oxygen atoms of the crown ether and two iodine atoms forming a hexagonal bipyramidal coordination polyhedron. The 18C6 molecule and the two halogen atoms form a hydrophobic coating for the lead atom which may be assumed to be the main reason of high extraction constants of the iodine complexes. For 10-coordinate lead ion (bidentate counter ions) the cis-syn-cis isomer of DC18C6 appears to be the best extraction reagent, while for 8-coordinate lead ion (monodentate halide anion) no difference between isomers was observed. 相似文献