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71.
《Journal of Coordination Chemistry》2012,65(11):2032-2038
A Zn(II) complex with an organoselenium substituted Schiff base, bis{2-[(benzylimino)methyl]-4,6-dihydroselenophenol}Zn(II), has been synthesized and characterized by elemental analyses and X-ray diffraction. Zn(II) is four-coordinated by two phenolate O and two imine N from two organoselenium substituted Schiff-base ligands, forming a distorted tetrahedral geometry. The title complex and its ligand were tested in vitro for their antibacterial and antitumor activity with the complex showing higher antibacterial and antitumor activities. 相似文献
72.
《Journal of Coordination Chemistry》2012,65(21):3565-3574
AbstractA new Zn(II) metal-organic framework (MOFs), [Zn(BTC)(HME)]·(DMAc)(H2O) (1, H3BTC =1,3,5-benzenetricarboxylic acid, HME?=?protonated melamine, DMAc?=?N,N-dimethylacetamide), has been synthesized under solvothermal conditions. In the structure of 1, the four-coordinate Zn(II) ions are connected by BTC3? ligands into a 3-D framework with (3)-connected utg-type topology. This MOF shows permanent porosity after lattice solvent removal with a calculated pore size distribution around 0.72?nm. With abundant N-donor sites and suitable pore size, the desolvated 1 (1a) was used as a drug carrier for the loading of anticancer drug 5-fluorouracil (5-Fu) molecules. Moderate 5-Fu loading capacity and long drug release time were observed for 1a. The computational simulation results reveal that strong H-bond interactions between the 5-Fu molecules and the nitrogen sites allow slow release of the drug 1a. In addition, the in vitro cytotoxicity of 1 and 5-Fu loaded 1a were also evaluated using MTT assays against human oral squamous cell carcinoma (SCC-251 and HSC-4). 相似文献
73.
《Journal of Coordination Chemistry》2012,65(7):1212-1220
A tetranuclear Zn(ΙΙ) complex, [Zn4L2(OAc)2(CH3OH)2] with an unsymmetric Salen-type bisoxime (H3L?=?6-hydroxy-4′,6′-dibromo-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol), has been synthesized and structurally characterized. There are two kinds of coordination geometry (trigonal bipyramidal and square pyramidal) in the Zn(ΙΙ) complex. The molecule has serious distortion probably from the asymmetry. The complex exhibits blue emission with the maximum emission wavelength λ max?=?423?nm when excited with 340?nm. 相似文献
74.
《应用有机金属化学》2017,31(1)
An organic polymeric resin was synthesized by anchoring p ‐aminobenzoic acid onto macroporous chloromethylated polystyrene beads, and was used for Zn(II) removal from aqueous solutions. The resin exhibited an initially rapid adsorption property for Zn(II) with equilibrium time of 10 h and the maximum adsorption capability approached 184.5 mg g−1. Optimum pH was 4.5. The mechanism of adsorption was investigated using kinetic, isotherm and thermodynamic models. The adsorption kinetic data were described well by a pseudo second‐order model with R 2 of 0.997. There was a negative ΔG (−17.98 kJ mol−1) and positive ΔH (13.58 kJ mol−1). HCl solution (1.0 mol l−1) could achieve an elution rate of 100%. The experimental data were well fitted by the Thomas model with R 2 of 0.9826. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
75.
Roser Pons Cristina Ibez Ana B. Buades Antonio Franconetti Angel Garcia‐Raso Juan J. Fiol Angel Terrn Elies Molins Antonio Frontera 《应用有机金属化学》2019,33(6)
We report the synthesis and X‐ray characterization of the N6‐benzyl‐N6‐methyladenine ligand (L) and three metal complexes, namely [Zn(HL)Cl3]·H2O ( 1 ), [Cd(HL)2Cl4] ( 2 ) and [H2L]2[Cd3(μ‐L)2(μ‐Cl)4Cl6]·3H2O ( 3 ). Complex 1 consists of the 7H‐adenine tautomer protonated at N3 and coordinated to a tetrahedral Zn(II) metal centre through N9. The octahedral Cd(II) in complex 2 is N9‐coordinated to two N6‐benzyl‐N6‐methyladeninium ligands (7H‐tautomer protonated at N3) that occupy apical positions and four chlorido ligands form the basal plane. Compound 3 corresponds to a trinuclear Cd(II) complex, where the central Cd atom is six‐coordinated to two bridging μ‐L and four bridging μ‐Cl ligands. The other two Cd atoms are six‐coordinated to three terminal chlorido ligands, to two bridging μ‐Cl ligands and to the bridging μ‐L through N3. Essentially, the coordination patterns, degree of protonation and tautomeric forms of the nucleobase dominate the solid‐state architectures of 1 – 3 . Additionally, the hydrogen‐bonding interactions produced by the endocyclic N atoms and NH groups stabilize high‐dimensional‐order supramolecular assemblies. Moreover, energetically strong anion–π and lone pair (lp)–π interactions are important in constructing the final solid‐state architectures in 1 – 3 . We have studied the non‐covalent interactions energetically using density functional theory calculations and rationalized the interactions using molecular electrostatic potential surfaces and Bader's theory of atoms in molecules. We have particularly analysed cooperative lp–π and anion–π interactions in 1 and π+–π+ interactions in 3 . 相似文献
76.
Four Zn(II) complexes, [Zn L 2(SO4)]n ( 1 ), [Zn L 4(H2O)2]?2(NO3)?4EtOH ( 2 ), [Zn L 2Cl2]? L ( 3 ), and [Zn L 2Br2]? L ( 4 ) ( L = uniconazole), were synthesized using a hydrothermal method and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. Complex 1 formed a one‐dimensional polymer chain. However, complexes 2 ‐ 4 were obtained as zero‐dimensional mononuclear coordination compounds. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all complexes show better antifungal activities than their ligands and mixtures. In addition, the interactions between the metal salts of complexes 1 ‐ 4 and uniconazole seem to be synergistic. Furthermore, the polymer chain structure of complex 1 significantly enhanced the bioactivity, especially against Botryosphaeria ribis ( I ). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity after the formation of Zn(II) complexes. The resulting data show that the HOMO–LUMO energy gaps of complexes 1 ‐ 4 (0.0578, 0.0946, 0.1053, and 0.1245 eV) are smaller than that of the free ligand (0.1247 eV) and correlate with the antifungal activity of the zinc complexes. 相似文献
77.
共沉淀法制备了Ru-Zn催化剂,考察了反应修饰剂ZnSO4和预处理对苯选择加氢制环己烯Ru-Zn催化剂性能的影响。结果表明,反应修饰剂ZnSO4可以与Ru-Zn催化剂中助剂ZnO反应生成(Zn(OH)2)3(ZnSO4)(H2O)盐。随反应修饰剂ZnSO4浓度增加,(Zn(OH)2)3(ZnSO4)(H2O)盐量的逐渐增加,Ru-Zn催化剂活性逐渐降低,环己烯选择性逐渐升高。因为(Zn(OH)2)3(ZnSO4)(H2O)盐中的Zn2+可以使Ru变为有利环己烯生成的缺电子的Ruδ+物种,而且还可以占据不适宜环己烯生成的强Ru活性位。但当反应修饰剂ZnSO4浓度高于0.41 mol·L-1后,继续增加ZnSO4浓度,由于Zn2+水解浆液酸性太强,可以溶解部分(Zn(OH)2)3(ZnSO4)(H2O)盐,Ru-Zn催化剂活性升高,环己烯选择性降低。但环己烯选择性却略微降低,这是由于ZnSO4溶液中大量的Zn2+可以与生成的环己烯形成配合物,稳定生成的环己烯,抑制生成的环己烯再吸附到催化剂表面并加氢生成环己烷。在ZnSO4最佳浓度0.61 mol·L-1下对Ru-Zn催化剂预处理15 h,Ru-Zn催化剂中助剂ZnO可以与ZnSO4完全反应生成(Zn(OH)2)3(ZnSO4)(H2O)盐,在该催化剂上25 min苯转化68.2%时环己烯选择性和收率分别为80.2%和54.7%。而且该催化剂具有良好的稳定性和重复使用性能。 相似文献
78.
Several N-alkyl/aryl-Se-alkyl/(aryl)selenocarbamates were prepared from various isocyanates and diselenides by reductive cleavage of Se-Se bond with the Zn/AlCl3 system in dry acetonitrile at 80℃. 相似文献
79.
Three novel Zn(II) complexes,[Zn4L1Cl4]-3H2O(1),[Zn4L2Cl4]-2DMF(2) and[Zn4L3Cl4]H2O(3),have been synthesized and structurally characterized.In these complexes,interesting 32-membered dodecadentate macrocyclic ligands were generated in situ by ’2 + 2’ type condensation reactions between a tetraamine and various dialdehydes.All the complexes are isostructurally tetranuclear Zn(Ⅱ) complexes,containing endogenous alkoxo and phenoxo bridges.Applications of the macrocyclic ligands as Zn2+ sensors have been investigated.Take H4L1 for example,it exhibits a 4-fold fluorescence enhancement upon the addition of 2 equiv.of Zn2+ in MeOH. 相似文献
80.
《合成通讯》2013,43(10):1549-1555
ABSTRACT A solvent free and expeditious method for tetrahydropyranylation and detetrahydropyranylation of alcohols, phenols and thiols is described using hydrated zirconia and 3,4-dihydro-2H-pyran (DHP). A comparison of this microwave-accelerated reaction with conventional heating condition is also presented. 相似文献