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1.
New derivatives of diaza-18-crown-6 have been prepared by the aminomethylation of N-alkylsulfonamides under the action of N,N-bismethoxymethyldiaza-18-crown-6.For Communication 23, see [1].Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 413–415, March 1986.  相似文献   

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A large number of derivatives of the diaza-18-crown-6 ligand have been synthesized and characterized. These derivatives have different alkyl or aryl side arms at the nitrogen donor atoms of the macrocyclic diazacrown ether. In some side chains additional donor atoms are available. These diazacrown ethers are used as ligands for the complexation of AgI in MeOH. The complexation reactions have been studied using potentiometric and calorimetric methods. The thermodynamic data show the absence of a lariat effect. The increase of the values of the reaction enthalpies are due only to changes in solvation of the different ligands.  相似文献   

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The crystal structure of a new complex of a diaza-crown ether having two side arms has been determined from X-ray diffraction data. The compound crystallizes in space group P1 with cell dimensions a = 9.982(1), b = 10.685(1), c = 20.376(2)Å, = 81.09(1), = 80.92(1), = 88.43(1)0, Z = 2. The structure has been solved by direct methods and refined to the final R value of 0.053 for 3458 observed reflections and 424 parameters. The diaza-18-crown-6 ligand adopts an approximate D3d conformation. The Na+ ion is held inside the molecular cavity of this macroring ligand and a ClO-4 oxygen coordinates with Na+. The average Na–-O (18-crown-6) and Na–-N bond lengths are 2.426(4) and 2.786(5)Å, respectively; the Na–-O (ClO-4) bond length is 2.472(4)Å. The mean cavity radius is 1.10 Å and the NN nonbonding distance is 4.605(6)Å.  相似文献   

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The reaction of {[UO2(HCOO)2(H2O)]} with diaza-18-crown-6 (DA18C6 = C12H26O4N2) in aqueous ethanol in the presence of formic acid yields the complexes {[DA18C6H2]·[UO2(HCOO)3]2} (I), [DA18C6H2]·[UO2(HCOO)4] (II), and [DA18C6H2]·(HCOO)2·(H2O)2 (III). The complexes are characterized using IR spectroscopy, chemical analysis, and powder X-ray diffraction. From the comparison of the structural and spectral characteristics of [DA18C6H2]·An2·(H2O)2n (where An = Cl?,NO 3 ? ,HCOO?,HSO 4 ? ; n = 0.1), correlations are derived between the conformation of the [DA18C6H2]2+ units and the conformation-sensitive frequencies. On the basis of these correlations, the conformations of the N+CCO and OCCO units were determined in the diazonia cations of compounds I and II and in [DA18C6H2]·[UO2(NO3)4]; the latter was prepared previously by reacting [UO2(NO3)2(H2O)2]·(H2O)4 with DA18C6 in ethanol in the presence of nitric acid.  相似文献   

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报道了双羟甲基-18-冠-6及其正丁基、烯丙基、酯基、羧酸基衍生物的合成。所合成的八种新冠醚化合物的结构已经IR、MS、NMR、元素分析证实。  相似文献   

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Interactions of diaza-18-crown-6 and diaza-15-crown-5, as electron donors, with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), as an electron acceptor, have been investigated spectrophotometrically in acetonitrile and chloroform solutions. The results indicated immediate formation of an electron donor-electron acceptor complex DA: [reaction in text] which is followed by two relatively slow consecutive reactions: [reaction in text]. The pseudo-first-order rate constants for the formation of the ionic intermediate and the final product have been evaluated at various temperatures by computer fitting of the absorbance time data to appropriate equations. The formation constants of the resulting DA complexes have also been determined. The influences of both the azacrown's structure and the solvent properties on the formation of DA complexes and the rates of subsequent reactions are discussed.  相似文献   

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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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Binding of the cationic dye auramine O (AuO) to the polysoap-type polymers poly(vinylbenzo-18-crown-6) (P18C6) and polyvinylbenzoglyme (PVBG) in water were studied by fluorimetry and dialysis. The quantum yield of P18C6-bound AuO was found to be 0.028, the value being 0.018 for AuO bound to PVBG. The intrinsic binding constants were found to be 2.2 × 104M?1 (P18C6) and 1.2 × 104M?1 (PVBG), the respective first binding constants being 317 and 63M?1. Addition of crown-ether-complexable cations such as K+, Tl+, or Cs+ converts the neutral poly(crown ether) into a polycation, causing repulsion of the cationic dye and a strong decrease in the AuO fluorescence. AuO fluorescence was also studied in the absence of polymer in ether solvents, giving θ values of 0.011 and 0.018 in THF and dioxane. Traces of water rapidly form a nonfluorescent species. Solutions of AuO in water without polymer present exhibit very strong fluorescence on addition of BPh4 anions owing to formation of AuO+, BPh4? ion pairs and higher aggregates.  相似文献   

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含二氮杂-18-冠-6-单元的向列型液晶化合物的合成和性质   总被引:1,自引:0,他引:1  
谢明贵  覃军  洪峰  王良御 《化学学报》1991,49(3):297-302
本文报道三种含芳酯的二氮杂-18-冠-6的合成。它们显示出向列型液晶的特性。探讨了分子结构对液晶性质的影响。冠醚液晶7在无机盐掺杂后是否仍有液晶性质与掺杂的无机盐阴离子的结构有关, 而与阳离子的种类无关。无机盐掺杂量对液晶清亮的影响也作了研究。  相似文献   

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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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Complex formation of Mg2+, Ba2+, and Pb2+ perchlorates with 3,3-diphenyl-3H-benzo[f]chromenes containing aza-and diaza-18-crown-6-ether or morpholine fragments was studied. The strong influence of the metal cations on the spectral characteristics of these organic ligands and on the kinetic of photochromic transformations was found. The results obtained were explained by the formation of carbonyl-“ capped” complexes of various structures. Faculte des Sciences de Luminy, Universite de la Mediterranee, UMR 6114 CNRS, 13288 Marseille, France. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 280—287, February, 2006.  相似文献   

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The complexation reaction between UO2 2+ cation with macrocyclic ligand, 18-crown-6 (18C6), was studied in acetonitrile–methanol (AN–MeOH), nitromethane–methanol (NM–MeOH) and propylencarbonate–ethanol (PC–EtOH) binary mixed systems at 25 °C. In addition, the complexation process between UO2 2+ cation with diaza-18-crown-6 (DA18C6) was studied in acetonitrile–methanol (AN–MeOH), acetonitrile–ethanol (AN–EtOH), acetonitrile–ethylacetate (AN–EtOAc), methanol–water (MeOH–H2O), ethanol–water (EtOH–H2O), acetonitrile–water (AN–H2O), dimethylformamide–methanol (DMF–MeOH), dimethylformamide–ethanol (DMF–EtOH), and dimethylformamide–ethylacetate (DMF–EtOAc) binary solutions at 25 °C using the conductometric method. The conductance data show that the stoichiometry of the complexes formed between (18C6) and (DA18C6) with UO2 2+ cation in most cases is 1:1 [M:L], but in some solvent 1:2 [M:L2] complex is formed in solutions. The values of stability constants (log Kf) of (18C6 · UO2 2+) and (DA18C6 · UO2 2+) complexes which were obtained from conductometric data, show that the nature and also the composition of the solvent systems are important factors that are effective on the stability and even the stoichiometry of the complexes formed in solutions. In all cases, a non-linear relationship is observed for the changes of stability constants (log Kf) of the (18C6 · UO2 2+) and (DA18C6 · UO2 2+) complexes versus the composition of the binary mixed solvents. The stability order of (18C6 · UO2 2+) complex in pure studied solvents was found to be: EtOH > AN ≈ NM > PC ≈ MeOH, but in the case of (DA18C6 · UO2 2+) complex it was : H2O > MeOH > EtOH.  相似文献   

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