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961.
962.
ZHANG Xiu-Tang ZHAN Xiao-ping WU Ding-Ming ZHANG Quan-Zheng CHEN Shu-mei YU Ya-qin LU Can-Zhong 《结构化学》2002,21(6)
The new oxovanadium (Ⅴ) complex, [PyH][VO2(L)] 1 (salicyladehyde 5-bromo salicyloylhydrazone is abbreviated as H2L; Hpy is protonated pyridine) was obtained from a refluxed solution of VOSO4 and H2L in acetonitrile-methanol-pyridine. Similarly, another new complex, [VO(L)(OCH3)] 2 was synthesized by refluxing VOSO4 and H2L in methanol-pyridine. Crystal data for 1: C19H15N3O5BrV, Mr = 496.2, monoclinic, P21/n, a = 7.1885(3), b = 9.2718(3), c = 28.803(1) (A), ( = 96.185(1)(, Z = 4 and V = 1908.6(1) (A)3; for 2: C15H12N2O5BrV, Mr = 431.1, monoclinic, P21/n, a = 12.202(2), b = 8.045(2), c = 16.604(3)(A), ( = 101.29(3)(, Z = 4 and V = 1598.4(2)(A)3. The structures of 1 and 2 have been determined by X-ray analyses and reveal that the coordination environments of V atoms in both complexes are of square-based pyramid. Three of the four based donor atoms are from the tridentate "ONO" donor ligand while the fourth is one terminal oxygen atom with the V(1)–O(3) distance 1.646(4) (A) for 1 and one -OCH3 group with the V(1)-O(3) distance 1.753(3)(A) for 2. The V(1)-O(4) terminals occupy the axial sites in both cases. The complexes are also characterized by IR and 1H NMR spectroscopies. 相似文献
963.
L. C. Du S. C. Tiong Q. Zhu Allan S. Hay 《Journal of polymer science. Part A, Polymer chemistry》2002,40(21):3579-3591
Zinc glutarates were synthesized from zinc oxides with varying purities via different stirring routes. The particle size and structure of these zinc glutarates were determined by wide‐angle X‐ray diffraction, transmission electron microscopy, and the laser particle size analyzer technique. The results demonstrated that the crystallinity and crystalline perfectness of zinc glutarate are the crucial factors that affect the catalytic activity for the copolymerization of carbon dioxide (CO2) and propylene oxide (PO). Additionally, the catalyst with a small particle size dramatically increased the yield of the copolymerization between CO2 and PO. High‐molecular‐weight and regular molecular structure poly(propylene carbonate)s (PPC)s were obtained from CO2 and PO with the synthesized zinc glutarates. Very high catalytic activity of 160.4 g polymer/g catalyst was afforded. The NMR technique revealed that the PPC copolymer exhibits an exact alternating copolymer structure. The relationships between the crystallinity and the particle size of catalyst with the catalytic activity are correlated and discussed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3579–3591, 2002 相似文献
964.
Adachi K Sugiyama Y Yoneda K Yamada K Nozaki K Fuyuhiro A Kawata S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(22):6616-6628
Novel triply hydrogen bonded suprastructures based on [M(tdpd)2(L)2]2- (H2tdpd=1,4,5,6-tetrahydro-5,6-dioxo-2,3-pyrazinedicarbonitrile, L=solvent) and melamine-analogous cations have been synthesized and characterized. The use of anions containing two AAA sets from [M(tdpd)2(L)2]2- together with cations containing one DDD set (A=hydrogen-bond acceptor, D=hydrogen-bond donor) leads to the formation of complementary triply hydrogen bonded modules in the solid state. In all cases, the building module is further extended via additional hydrogen-bonding interactions to produce a tape, and tapes are assembled into sheets. These results show that a hydrogen-bonded module consisting of different kinds of building blocks, one of which is a metal complex that includes hydrogen-bond acceptor sites and the other is a hydrogen-bond donor molecule, will be attractive for constructing metal-containing supramolecular systems by the self-assembly technique. 相似文献
965.
报道了一种新的杂多化合物[HN(C_2H_5)_3]_4-[Mo_3~VMo_6~(VI)V_7~(IV)O_(40)(PO_4)]·2[N(C_2H_5)_3]的合成,并用元素分析、EPR、IR谱、及X--射线单晶衍射等手段进行了表征。结果表明,该杂多酸盐属于单斜晶系,空间群P21/n,a=14.0841(3),b=14.2505(3),c=19.6089(3)?b=94.213(1),V=3925.0(1)?,Z=2,Dc=2.171g/cm3,Mr=2566.18,m=2.284mm-1,F(000)=2516,R=0.0477,wR=0.0945.杂多阴离子是1个16金属笼状物,笼中心包含1个PO4四面体客体。 相似文献
966.
含八齿苦味酸根的超分子苦味酸钾的合成和结构 总被引:1,自引:0,他引:1
A supramolecular complex, [Kpic]n (pic- is picratol, (NO2)3C6H2O-), has been synthesized unexpectedly in acetone solution, and characterized by elemental analysis, IR and X-ray crystallography. In the complex, the K+∶pic- is 1∶1, and one K(Ⅰ) ion is surrounded by six picrate anions, one picrate anion can coordinate to six K(Ⅰ) ions. The coordination number of every potassium atom is eight. Interestingly, the picratol adopts an eight-coordinated ideal mode unreported. CCDC: 630627. 相似文献
967.
A biocompatible surfactant-n-dodecylammonium α-glutamate (GDA) with biodegradable and biocompatible properties was synthesized, and the phase behavior
and the structural properties of GDA/n-pentanol/water system was studied by small-angle X-ray diffraction, electron spin resonance, and freeze-fracture transmission
electron microscopy (FF-TEM). In the ternary phase diagram of GDA/n-pentanol/water system, there exist three isotropic regions—O/W, bicontinuous, and W/O structures, and two anisotropic regions—hexagonal
liquid crystal (HEX), and lamellar liquid crystal (LLC) regions. UV irradiation causes the decrease in the interlayer space,
d, of lamellar liquid crystal and in the radius, r, of column aggregates of hexagonal liquid crystal, but it has little effect on the structure of O/W and W/O microemulsions. 相似文献
968.
合成了一种新颖有机-无机杂化配位聚合物{[C12H28N2] [(Pb3I8)(DMF)2]•2DMF}n, 并进行了红外、紫外、热重表征, 采用X射线衍射方法确定了晶体结构. 结构解析表明, 整个分子由阳离子(双质子化的N,N'-二丁基哌嗪)及聚阴离子链([(Pb3I8)(DMF)2]n2-)组成, 它们之间由静电作用结合在一起形成一维链状配位聚合物. 依据晶体结构数据, 采用Gaussian03程序对产物进行量子化学计算. 相似文献
969.
970.
The reactions of a series of 5-alkyl-2-thiophenedithiocarboxylates with nickel(II) chloride afforded two types of complexes, blue nickel(II) complexes with two terminal dithiocarboxylate ligands, [Ni(S2CTR)2] and violet nickel(II) complexes with perthio- and dithiocarboxylate ligands, [Ni(S2CTR)(S3CTR)] (where T = 2,5-disubstituted thiophene, R = CnH2n+1, n = 4, 6, 8, 12, 16). The blue monomers are preferred for the shorter chains (C4 and C6) and the violet compounds form exclusively for the longer chains (C8, C12, and C16) in the alkylthiophene complexes. In addition to the above series, [Ni(S2CTCH3)2], was prepared in a one-pot reaction in THF and both the blue and violet products were isolated. It was possible to convert the blue complexes [Ni(S2CTR)2] (R = butyl, hexyl) into the corresponding violet complexes [Ni(S2CTR)(S3CTR)] after stirring in THF solutions for prolonged periods of time. Liquid-crystalline properties of these complexes were examined by DSC and POM. The violet complexes with C8 and C12 alkyl chains showed liquid-crystalline properties. 相似文献