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1.
The preparation of trans-[Co(NH3)4(CH3NH2)Br]2+ and trans-[Co(NH3)4(CH3NH2)-(NO3)]2+ complexes is described. The UV-VIS spectra of the complexes indicate a decrease of the ligand field compared to the parent pentaammines. Infrared spectra match with the pattern of the corresponding pentaammines. The catalyzed (by Hg2+) aquation of the trans-bromomethylamine complex go under retention of the stereochemical configuration. The base hydrolysis (studied at 25°C) products show trans to cis rearrangement for both complexes. 1H NMR spectroscopy is used for identification of the stereochemical configuration of the compounds.  相似文献   

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1 INTRODUCTION The chalcogenidometallates with open frame- works have attracted considerable interest as pos- sible zeolite-like materials, of which highly interes- ting properties could be expected. Over the last de- cades a large number of thioanti…  相似文献   

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An unusual two-dimensional zinc phosphate with pendant phosphate groups, projecting into the inter-lamellar space between the layers, has been synthesized and is shown to transform into a three-dimensional structure with 16-membered bifurcated channels, giving evidence for the building up process in the formation of open-framework structures.  相似文献   

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The reactions of ten metastable immonium ions of general structure R1R2C?NH+C4H9 (R1 = H, R2 = CH3, C2H5; R1 = R2 = CH3) are reported and discussed. Elimination of C4H8 is usually the dominant fragmentation pathway. This process gives rise to a Gaussian metastable peak; it is interpreted in terms of a mechanism involving ion-neutral complexes containing incipient butyl) cations. Metastable immonium ions ontaining an isobutyl group are unique in undergoing a minor amount of imine (R1R2C?NH) loss. This decomposition route, which also produces a Gaussian metastable peak, decreases in importance as the basicity of the imine increases. The correlation between imine loss and the presence of an isobutyl group is rationalized by the rearrangement of the appropriate ion-neutral complexes in which there are isobutyl cations to the isomeric complexes containing the thermodynamically more stable tert-butyl cations. A sizeable amount of a third reaction, expulsion of C3H6, is observed for metastable n-C4H9 +NH?CR1R2 ions; in contrast to C4H8 and R1R2C?NH loss, C3H6 elimination occurs with a large kinetic energy release (40–48 kJ mol?1) and is evidenced by a dish-topped metastable peak. This process is explained using a two-step mechanism involving a 1,5-hydride shift, followed by cleavage of the resultant secondary open-chain cations, CH3CH+ CH2CH2NHCHR1R2.  相似文献   

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采用水热合成法以丁二胺作为模板剂合成了钴的有机二膦酸超分子化合物[NH3(CH2)4NH3]Co(hedpH2)2(H2O)2 [hedpH4 = 1-羟亚乙基二膦酸, CH3C(OH)(PO3H2)2]。用元素分析、红外光谱、紫外-可见光谱、热重分析以及单晶结构解析对其进行了表征。该化合物的化学式为:C8H30N2CoO16P4,Mr = 593.15,晶体属单斜晶系,空间群C2/c,晶胞参数a = 16.128(2), b = 12.427(1), c = 12.610(2) ? b = 121.389(9), V = 2157.3(4) 3, Z = 4, Dc = 1.826 g/cm3, m(MoKa) = 1.172 mm-1, F(000) = 1228。结构用直接法解出,最终偏离因子R = 0.0285, wR = 0.0747。该化合物的结构包含单核的Co(hedpH2)2- 阴离子,阴离子之间通过氢键连结形成具有空隙的三维超分子骨架结构,双质子化的丁二胺分子位于空隙中。  相似文献   

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Monoperoxovanadium(V) complexes, [NH3(CH2)2NH3][VO(O2)(ox)(pic)].2H2O (1) and [NH3(CH2)2NH3][VO(O2)(ox)(pca)] (2) [NH3(CH2)2NH3 = ethane-1,2-diammonium(2+), ox=oxalate(2-), pic=pyridine-2-carboxylate(1-), pca=pyrazine-2-carboxylate(1-)], were synthesized and characterized by X-ray analysis, IR and Raman spectroscopies. The five equatorial positions of the pentagonal bipyramid around the vanadium atoms are occupied by the eta2-peroxo ligand, two oxygen atoms of the ox, and the nitrogen atom of the pic or pca ligands, respectively. The oxo ligand and the oxygen atom of pic or pca are in the axial positions. Networks of X-HO (X=C, N or O) hydrogen bonds, and pi-pi interactions between aromatic rings in and anion-pi interactions in , determine the molecular packings and build up the supramolecular architecture. Three stereochemical rules for occupation of the donor sites in two-heteroligand [VO(O2)(L1)(L2)] complexes (L1, L2 are bidentate neutral or differently charged anionic heteroligands providing an OO, NN or ON donor set) are discussed. and crystallize as racemic compounds. The 51V NMR spectra proved that the parent complex anions of and partially decompose on dissolution in water to the monoperoxo-ox, -pic or -pca complexes.  相似文献   

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A new cobalt(II) carboxylate-phosphonate, namely, Co[HO2C(CH2)3NH(CH2PO3H)2]2, with a layered architecture has been synthesized by hydrothermal reactions. The Co(II) ion in the title compound is octahedrally coordinated by six phosphonate oxygen atoms from four carboxylate phosphonate ligands. Neighboring CoO6 octahedra are interconnected by phosphonate groups into a 2D layer with a 4,4-net topology. Adjacent layers are further cross-linked via hydrogen bonds between the noncoordinate carboxylate groups and noncoordinate phosphonate oxygens. The ac and dc magnetic susceptibility and magnetization measurements indicate that Co[HO2C(CH2) 3NH(CH2PO3H)2]2 is a canted antiferromagnet with T(c) = 8.75 K.  相似文献   

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A hydrothermal reaction of iron acetylacetonate, phosphoric acid, HF, N, N′‐bis(3‐aminopropyl)ethylenediamine and water at 150 °C gave rise to a new iron phosphate, [H3N(CH2)3NH2(CH2)2NH2(CH2)3NH3][Fe3F6(HPO4)2(PO4)] · 3H2O ( I ). The structure consists of Fe(1)O4F2, Fe(2)O3F3 octahedral and P(1)O3(OH) and P(2)O4 tetrahedral building units connected through their vertices to form fragments of tancoite‐type units. The tancoite‐type units are linked through the phosphate tetrahedra forming an unusual iron phosphate with a hitherto unknown low‐dimensional structure with three‐iron center.Magnetic studies indicate a complex behavior at low temperature and the high‐temperature data (150 — 300 K) has a Curie‐Weiss behavior. The calculated room temperature magnetic moment is 6 μB per Fe atom, and the Neel temperature, TN = 46K. Crystal data: orthorhombic, space group = I212121 (no. 24), a = 9.9042(11), b = 12.8865(14), c = 19.783(2)Å, U = 2524.9(5), Z = 4.  相似文献   

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Wang  Shutao  Wang  Enbo  Hou  Yu  Li  Yangguang  Wang  Li  Yuan  Mei  Hu  Changwen 《Transition Metal Chemistry》2003,28(6):616-620
A novel organic/inorganic hybrid molybdenum phosphate, [NH3(CH2CH2)2NH3]3[NH3(CH2CH2)2NH2]Na5-[Mo6O12(OH)3(PO4)(HPO4)3]2·4H2O (1), involving molybdenum presented in V oxidation, has been hydrothermally prepared and characterized by elemental analysis, i.r., u.v.–vis., x.p.s., t.g. and single crystal X-ray diffraction. The structure of the title compound (1) may be considered to consist of two [Mo6O12(OH)3(PO4)(HPO4)3] units bonded together with NaO6 octahedra, forming dimers. Further, these dimers connect with each other through four Na+ cations as bridges, giving rise to novel one-dimensional chain-like skeleton. Piperazines exist among inorganic chains acting as charge balancing cations.  相似文献   

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The two‐dimensional zinc phosphate [H3N(CH2)3NH3]0.5[Zn2(PO4)(HPO4)], has been synthesized hydrothermally using 1,3‐diaminopropane as the template. Its structure contains an inorganic framework with three‐, four‐, or six‐membered rings, built from PO4, PO3(OH) and ZnO4 tetrahedral moieties sharing vertexes. The protonated 1,3‐diaminopropane molecules interact with the framework through hydrogen bonds. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

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Nucleophilic substitution reactions of the monosubstituted anions [B12H11X]2–, where X = OC(O)CH3, OH, SCN, and I, with pentanoic acid were studied. The obtained compounds were shown to contain the [B12H10X{OC(O)(CH2)3CH3}]2– anions.  相似文献   

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Three ligands, 2-(3-(carboxymethyl)-1,10-phenanthroline-[5,6-d]imidazole-1-yl)acetate (CPIA), 2-(benzo[d][1,3]dioxol-4-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (BIP), and 2-(9H-carbazol-3-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (CIP), and their complexes, [Co(phen)2(CPIA)]3+ (1) (phen = 1,10-phenanthroline), [Co(phen)2(BIP)]3+ (2), and [Co(phen)2(CIP)]3+ (3), have been synthesized and characterized. Binding of the three complexes with calf thymus DNA (CT-DNA) has been investigated by spectroscopic methods, cyclic voltammetry, and viscosity measurements. The three complexes bind to DNA through an intercalative mode, and the size and shape of the intercalative ligands have significant effects on the binding affinity of complexes to CT-DNA.  相似文献   

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