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Synthesis and Crystal Structure of Supramolecular Adducts of Macrocyclic Cavitand Cucurbituril with Chromium(III) and Nickel(II) Aqua Complexes 总被引:1,自引:0,他引:1
Samsonenko D. G. Geras'ko O. A. Mit'kina T. V. Lipkowski J. Virovets A. V. Fenske D. Fedin V. P. 《Russian Journal of Coordination Chemistry》2003,29(3):166-174
Supramolecular compounds {[Cr(H2O)6](C36H36N24O12)}(NO3)3 · 13H2O (I) and {[Ni(H2O)6]2(C36H36N24O12)}(SO4)2 · 16H2O (II) were obtained from aqueous solutions of chromium nitrate or nickel sulfate and the macrocyclic cavitand cucurbituril. According to X-ray diffraction analysis data, the cucurbituril molecule is closed from both sides by metal aqua complexes due to the formation of hydrogen bonding between the cucurbituril CO groups and aqua ligands. Compound I has a chain structure, while the structure of compound II is layered. Modes of cucurbituril coordination, depending on the size and charge of the metal cation, are discussed. 相似文献
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A. A. Tripolskaya E. A. Mainicheva T. V. Mit'kina O. A. Geras'ko D. Yu. Naumov V. P. Fedin 《Russian Journal of Coordination Chemistry》2005,31(11):768-774
Slow evaporation of solutions of Sc and Eu nitrates with macrocyclic cavitand cucurbit[6]uril gives crystals of isostructural complexes [Sc(NO3)(H2O)4(C36H36N24O12)](NO3)2 ? 8.5H2O (space group Pna21, a = 32.0065(18) Å, b = 14.7904(8) Å, c = 11.5774(6) Å, V = 5480.6(5) Å3, Z = 4) and [Eu(NO3)(H2O)4(C36H36N24O12)](NO3)2 ? 6.75H2O (space group Pna21, a = 31.9525(17) Å, b = 14.7203(8) Å, c = 11.8592(6) Å, V = 5578.0(5) Å3, Z = 4). The metal to ligand ratio in these complexes is 1 : 1; the complexes are obtained at 0.025–0.1 mol/l concentrations of the metals in solutions. With higher lanthanide concentrations (0.7–1 mol/l), the 2 : 1 complex with cucurbit[6]uril is formed of the composition [{ Gd(NO3)(H2O)5}2(C36H36N24O12)](NO3)4 ? 6.5H2O (space group \(P\bar 1\), a = 13.3972(6) Å, b = 14.4994(5) Å, c = 18.3290(8) Å, α = 73.5610(10)°, β = 87.2590(10)°, γ = 87.5540(10)°, V = 3409.4(2) Å3, Z = 2) and isotypical complex [{Gd(NO3)(H2O)5}2{(C5H5N) ? (C36H36N24O12)}](NO3)4 ? 8H2O with a pyridine molecule inside the cucurbit[6]uril cavity (space group P21/n, a = 14.8263(6) Å, b = 13.3688(7) Å, c = 18.5970(9) Å, β = 107.5860(10)°, V = 3513.8(3) Å3, Z = 2). According to X-ray diffraction data, the metal atoms of the title complexes coordinate the O atoms in portals of cucurbit[6]uril molecules. 相似文献
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