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101.
以十四酸根阴离子柱撑Zn-Al水滑石Zn0.77Al0.22(OH)2.0.22C13H27COO.0.81 H2O(记为ZnAl-14A)为预撑前体,在水溶液中用离子交换法将以2∶17缺位杂多酸根离子(P2Mo16VO61)11-记为(P Mo V)为配体的稀土杂多配阴离子Ce(P2Mo16VO61)219-(记为Ce(PMoV)2)插层组装到水滑石层板间,合成了一种具有大的层间距(3.37 nm)的超分子插层材料Zn0.77Al0.23(OH)2.0.0105[Ce(P1.9Mo15.7V1.1O61)2].0.011C13H27COO.0.83H2O(记为ZnAl-Ce(PMoV)2)。用ICP,IR,XRD和DTA对产物的组成和结构进行了表征。结果表明,该产物中Ce(PMoV)2配阴离子沿其长轴垂直于层板的方向分布于水滑石层间;产物具有规整的层状结构和热稳定性;产物对乙酸与正丁醇的酯化反应,二甘醇的脱水-环化反应和H2O2氧化环己烷的反应有良好的催化性能,且易于回收重复使用。 相似文献
102.
Naoya Inazumi Shunzo Yamamoto Yoshimi Sueishi 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):33-39
The inclusion complexation of p-sulfonatocalix[6]arene (Calix-S6) with three kinds of phenothiazine dyes was studied spectrophotometrically in a mixture
of a room-temperature ionic liquid [bmim]BF4 (1-butyl-3-methylimidazolium tetrafluoroborate) and ethanol. We have determined the association constants of Calix-S6 with
phenothiazine dyes under external static pressure up to 767 bar in the [bmim]BF4-ethanol and alcohol-water mixtures. With increasing external pressure, the inclusion equilibrium in the alcohol-water mixtures
was shifted to the dissociation side. Conversely, the inclusion equilibrium of methylene blue (MB) and azure A (AA) in the
ionic liquid mixture was shifted to the association side. From the analysis of the pressure effects, the reaction volumes
ΔV for inclusion complexation were estimated as −7 to 9 cm3 mol−1 in the [bmim]BF4-ethanol mixture and 20–32 cm3 mol−1 in the alcohol-water mixtures. Based on the results, we have suggested that there is a competing complexation between the
included dye and [bmim]BF4 molecules in the ionic liquid. 相似文献
103.
硫氰酸根的结构为N≡C-S-,其两端的N原子和S原子分别有一对和三对孤对电子,因此,硫氰酸根可采用多种不同的配位模式与金属离子发生配位。硫氰酸根可作为单齿配体与一个金属离子配位,形成M-SCN或M-NCS的单核配合物,也可以作为桥联配体同时与两个、三个甚至四个金属离子配位形成多核配合物犤1~3犦;另一方面,硫氰酸根是一个具有一定共轭性的偶极子,可传递磁相作用。因此,选择硫氰酸根作为桥联配体,将多个顺磁金属离子桥联形成一维、二维或三维结构的多核金属配合物分子,并研究它们的磁性已成为分子磁学的一个研究领域… 相似文献
104.
105.
B. T. Ibragimov S. A. Talipov T. F. Aripov 《Journal of inclusion phenomena and macrocyclic chemistry》1994,17(4):317-324
The structures of gossypol complexes are extremely sensitive to the halogenomethane present as the guest; e.g. changing the number of Cl atoms in chloromethane derivatives changes the structure of the gossypol complex. The crystals of C30H30O8·CH2Cl2 are monoclinic, space groupC2/c,a=21.320(4),b=19.199(6),c=15.765(2)Å, =113.05(2)o,V=5916(2)Å3,Z=8,D
x=1.35 g/cm3,T=295 K. The structure has been solved by direct methods and refined to the finalR value of 0.084 for 1828 reflections. In the structure H-bonded gossypol molecules form columns, generating channels in the structure which are filled by guest molecules. After decomposition (desolvation) monocrystals of the complexes are conserved without destruction, in which there are rather wide and empty channels though slightly smaller than in the complex. An attempt is made to explain some peculiarities of the behavior of the gossypol polymorph formed on the basis of its structure with empty channels.
Supplementary data relevant to this article have been deposited with the British Library Publication No. SUP 82165 (17 pages). 相似文献
106.
A novel chiral Salen ligand with a glucose moiety was synthesized from the condensation of 1,2:5,6-di-O-isopropylidene-3-O-methylene-[5-(3-tert-butyl-2-hydroxy benzaldehyde)]-α-D-glucofuranose with (1R,2R)-1,2-diaminocyclohexane. Several chiral complexes of Mn3+, Fe3+, Co2+ and Cu2+ were prepared from this ligand. Both the ligand and the complexes were characterized by elemental analysis, NMR, IR, MS, and UV-Vis. 相似文献
107.
Himansu Sekhar Sahoo S. Mahalakshmi Md. Hedayetullah Mir R. Raghunathan 《Tetrahedron letters》2007,48(5):761-765
A remarkable upfield shift of the pyα protons of complexed 2,2′-bipyridine in [cis-Pd(bpy)(NO3)2] is observed which is considered to originate from the anisotropic influence of suitably positioned coordinated nitrate anions around the Pd(II) centre of the molecule. A typical complexation-induced downfield shift is observed for the NH2 protons in [cis-Pd(en)(NO3)2] where ‘en’ stands for ethylenediamine. 相似文献
108.
Mössbauer parameters of frozen aqueous solutions of Sn(ClO4)2 in 0.5 M HClO4 did not change with the concentration of NaClO4, so that it was used to keep the ionic strength at the desired level. When NaCl was added into Sn(ClO4)2 solutions, isomer shift did not change, but quadrupole splitting did. Therefore, stability constants were calculated from the quadrupole splitting data, which were in good agreement with the published values. The observed spectra could be resolved into components. 相似文献
109.
110.
合成了六种轻希土硫氰酸盐与标题不饱和冠醚的新固体配合物,进行了元素分析,摩尔电导率、DTA、UV、IR和XPS等表征.对Ln(NCS)3·L和Ln(NCS)3的XPS研究中,得到它们组成原子芯能级电子(Ln3d5/2,Ols,Nls,S2p)的结合能信息;观察到除Y3d5/2外Ln3d5/2(Ln=La、Ce、Pr、Nd、和Sm)的伴峰结构,Ln3d5/2结合能与原子序数呈线性关系,并推断类似化合物Pm3d5/2结合能在1035eV附近. 相似文献