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1.
Molecular machine is a new born research field1-5, Stoddart and co-workers firstly reported a molecular shuttles in 19916. In molecular machine a cyclic (bead) moves back and forth like a shuttles between two or more groups (station) having noncovalent interaction with a bead. Dumbbell-shaped component is the key intermediate for the synthesis of molecular machines7. One of the approaches for control movement of the bead is based on coordination reaction intrigue. In our protocol, a ligand…  相似文献   

2.
A new lead(Ⅱ) carboxylate-sulfonate has been hydrothermally synthesized and characterized by X-ray single-crystal and elemental analyses. It crystallizes in triclinic, space group P, with a = 8.1573(6), b = 9.4663(7), c = 12.7488(9) , α = 89.2320(10), β = 80.7380(10), γ = 77.9760(10)°, Z = 2, V = 950.10(12) 3, Mr = 599.57, Dc = 2.096 g/cm3, μ = 9.032 mm-1, F(000) = 572, the final R = 0.0412 and wR = 0.1035. It has a 1D chain structure, and the Pb(Ⅱ) is six-coordinated. Two PbO6 polyhedra are interconnected via edge-sharing into a two-core unit. Such units are further interconnected by 3-sulfonato-benzoic acids into 1D chains which are linked by hydrogen bonds into a layer structure. The 4,4'-bipyridines are located at the interlayer space and link the layers into a supramolecular structure by π-π stacking interactions.  相似文献   

3.
A new trinuclear nickel complex,[Ni3(pdc)3(2,2'-bipy)3(H2O)2]·2H2O(H2pdc = pyridine 2,6-dicarboxylic acid,2,2'-bipy = 2,2'-bipyridine) has been hydrothermally synthesized and characterized by IR,elemental analysis and X-ray diffraction methods.Crystal data for this complex:monoclinic,space group P21/n,a = 21.206(4),b = 10.002(2),c = 28.066(6),β = 108.18(3)°,C51H41N9Ni3O16,Mr = 1212.06,V = 5.656(2) nm3,Dc = 1.423 g·cm-3,μ(MoKα) = 1.062 mm-1,Z = 4,F(000) = 2488,GOOF = 1.034,the final R = 0.0543 and wR = 0.1237 for 6149 observed reflections with Ⅰ 2σ(Ⅰ).In the complex,three nickel(Ⅱ) ions are bridged by the pyridine 2,6-dicarboxylic acid groups,and all nickel(Ⅱ) ions are seven-coordinated by nitrogen atoms of 2,2'-bipyridine and pyridine 2,6-dicarboxylic acid and oxygen atoms from pyridine 2,6-dicarboxylic and water to adopt a severely distorted pentagonal bipyramidal geometry.The emission and excitation peaks of the complex in ethanol solutions are located at 336 and 316 nm,respectively.  相似文献   

4.
Introduction Recently cyano bridged 3d-4f heterometallic compounds have attracted much attention because of their interesting structures and magnetic characteristics.1 The most successful and often the sole strategy for preparing these materials consists in assembling two building blocks that are transition and lanthanide metal complexes, one with terminal ligands that are able to act as bridging ligands and the other with available co-ordination sites. The [M(CN)4]2- (M=Ni, Pd, Pt),1f,2 [M…  相似文献   

5.
A novel pyridinium salt, 2,4-bis[p-(N,N-dimethylamino)styryll-N-metlayl pyridinium iodide (BMSPI) was synthesized and characterized by TG, ^1H NMR spectroscopy and elemental analysis, and the reaction process was studied by using ES-MS. When BMSPI was pumped by a pulsed 1064 nm, 50 ps laser beam, it manifests highly efficient TPA (Two-Photon Absorption) and up-conversion superradiance. The up-conversion efficiency was 6.0% at the pump energy of 4-6 mJ and the lifetime of two-photon fluorescence was measured as 59 ps.  相似文献   

6.
In recent years, the research on rare earth became a focus, and a lot of rare earth complex compounds with AB2O4 stoichiometry were prepared1-3. The compound SnDy2O4 is expected to spinel-type phase while it exhibits a new structure type. SnDy2O4 was prepared by the thermal decomposition of the oxalate precursor that was prepared by rheological phase reaction method. SnO(AR), Dy2O3(99.9%) and H2C2O4·2H2O are ground in molar ratio 1:1:4.1, and placed into the reaction apparatus. …  相似文献   

7.
1 INTRODUCTION Polyoxometallates are of great interest not only for their structural variety but also for their un- expected properties[1, 2]. These inorganic anions had been widely investigated in catalysis, biology, me- dicine, magnetochemistry and materials science[3~6]. Especially, the studies on the organic ligands coor- dinated by polyoxometallates might help to under- stand the catalytic mechanism of polyoxometallates. In recent years, several octamolybdates containing organic l…  相似文献   

8.
A convenient and high yield preparation of 4, 4′-dicarboxy-2, 2′-bipyridine from the oxidation 4, 4′-dimethyl-2, 2′-bipyridine with potassium dichromate in sulfuric acid is reported.  相似文献   

9.
A new metal-organic complex [Mn2(PDC)2(bipy)2(H2O)2] (H2PDC = 2,4-pyridine-dicarboxylic acid, bipy = 2,2′-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The compound crystallizes in triclinic, space group P ^-1 with a = 7.376(3), b = 9.990(4), c = 11.950(5) A^°, α= 75.217(5), β = 78.052(5), γ = 70.655(5)°, V = 796.0(5)A^°3, C34HE6Mn2N6O10, Mr = 788.49, De = 1.645 g/cm^3,μ(MoKa) = 0.866 mm^-1, F(000) = 235, Z = 1, the final R = 0.0425 and wR = 0.0700 for 1971 observed reflections (I 〉 2σ(I)). In the crystal structure, the manganese atom is six-coordinated by two carboxylate oxygen atoms from two different PDC ligands, one aqua ligand, and three nitrogen atoms from 2,2′-bipy and PDC ligands, giving a distorted octahedral geometry. It exhibits a three-dimensional supramolecular network defined by O-H…O hydrogen-bonding interactions.  相似文献   

10.
1 INTRODUCTION In recent years many efforts have been devoted to the preparation and characterization of pendant- arm macrocyclic complexes due to the fact that the ligating groups attached to the macrocyclic skeleton can offer additional donor groups to maintain the coordination sphere of metals in the macrocycles[1~7]. In this way, functionalized pendant arm macrocyc- lic complexes have been designed and prepared so as to mimic the structures and properties of certain metalloenzymes and…  相似文献   

11.
The stereoselecfive synthesis of typhoniside, a new cerebroside isolated from Typhonium giganteum Engl. was accomplished.Cerebrosides are a kind of glycolipids highly enriched on the surface of myelin-producing cells and are composed by C18-4,8-sphingadienine, a-hydroxy acid and a saccharide head. It was the first time that cerebrosides were isolated from this traditional Chinese medicine (TCM) by us. In this paper, C18-4,8-sphingadienine was synthesized from D-xylose via a SN2 type reaction, α-Hydroxy acid was prepared from (R)-4-hydroxyte-trahydrofuran-2-one, which in turn could be obtained from Lascorbic acid.  相似文献   

12.
The complex {[Mn(H2O)4(3, 3?-azpy)](3, 3?-azpy)3(PF6)2}n (3, 3?-azpy = 3, 3?- azobispyridine) has been synthesized and characterized. The crystal (C40H40F12MnN16O4P2, Mr = 1153.76) belongs to the triclinic system, space group P ī with the following crystallographic parameters: a = 10.761(2), b = 11.040(2), c = 23.365(4) ?, ( = 85.52(1), ( = 82.69(1), ( = 70.44(1)°, V = 2592.5(8) ?3, Dc = 1.478 g/cm3, ((MoK() = 4.16 cm-1, F(000) = 1174, Z = 2, final R = 0.0493 and wR = 0.1158 for the observed reflections (I > 2.00((I)). The X-ray analysis revealed that manganese(Ⅱ) cation coordination environment is a distorted octahedral geometry, and the Mn2+ cation is coordinated by four oxygen atoms of water in the equatorial plane, while the two nitrogen atoms of 3, 3?-azpy occupy the axial positions. The complex forms a one-dimensional chain structure via 3, 3?-azpy bridging ligand.  相似文献   

13.
1 INTRODUCTION In recent years, coordination polymeric frame- works have attracted great attention not only due to their potential applications in the areas of magnetism, nonlinear optics, electronics, catalysis, and molecu- lar recognition and sorption but also to their intri- guing structure topologies[1~8]. The coordination polymers can be specially designed by careful selec- tion of the metal ions with definite coordination geometry, the structure of the connecting ligands, the nature…  相似文献   

14.
2H-3, 1-Benzoxazine heterocyclic compounds are a series of potent nonsteroidal pro- gesterone receptor agonists1-3 and have many other applications such as carbonaceous electrode, plant growth regulating and anti-stress activities4-6, etc.. Comparing to other benzoxazine series, such as 1, 4-benzoxazine, 2H-1, 3-benzoxazine, etc., little attentions have been paid for this series of compounds. There is only one method for the preparation of 2H-3, 1-benzoxazine, e.g. cyclocondensation of o-amin…  相似文献   

15.
16.
1 INTRODUCTION In recent years, the rational design and synthesisof metal-directed supramolecular frameworks throughintermolecular hydrogen bonds, π-π stacking interac-tion or other weak interactions have received muchattention because of their interesting molecular topo-logies and various potential applications in catalysis,superconductor, magnetism, nonlinear optics, sen-sors and molecular recognition[1~4]. On the otherhand, the attachment of mono- or polypyridyl frag-ments to a ferr…  相似文献   

17.
A new metal-organic coordination polymer [Co(2-pya)2(4,4'-bipy)]2n-[(4,4'- bipy)0.5· H2O]2n (2-pya = 2-pyridinecarboxylic acid, 4,4'-bipy = 4,4'-bipyridine) 1 has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in tetragonal, space group I41/a with a = b = 22.719(2), c = 10.710(2)/k, V = 5527.8(14) A3, C54H46N10Co2O10, Mr= 1112.87, Dc = 1.337 g/cm3,μ(MoKa) = 0.665 mm-1, F(000) = 2296, Z = 4, the final R = 0.0633 and wR = 0.1096 for 1261 observed reflections (I 〉 2σ(I)). It exhibits a one-dimensional chain-like structure constructed by mixed ligands of 2-pyridinedicarboxylic acid and 4,4'-bipyridine.  相似文献   

18.
安哲  高晶  朱玲 《结构化学》2014,33(7):1063-1068
A new coordination polymer, namely [Ca(HOABDC)]n(1, H3 OABDC = 5-oxyacetateisophthalic acid), has been synthesized through hydrothermal reactions of Ca(NO3)2 and H3 OABDC. The title compound crystallizes in monoclinic, space group P21/c with a = 4.3043(2), b = 21.4959(11), c = 10.7450(6) A, β = 91.411(5)o, V = 993.88(9)A3, C10H6O7 Ca, Mr = 278.23, Z = 4, Dc = 1.859 g/cm3, F(000) = 560, μ = 0.659 mm-1, the final R = 0.0328 and wR = 0.0670 for 1469 observed reflections(I 2A(I)). Single-crystal X-ray structural analysis reveals that compound 1 features 1D Ca(Ⅱ)-carboxylate chain-shaped subunits, which are further connected together via HOABDC2- ligands into a 3D(6,6)-connected nia-type hybrid framework. Moreover, the luminescent property and thermal stability of 1 were also investigated.  相似文献   

19.

The synthesis of the binuclear complex [(tren)Cu(4,4'-bipy)Cu(tren)] (ClO4)4 where tren = tris(2-aminoethyl) amine and 4,4'-bipy = 4,4'-bipyridine, is described. Single-crystal X-ray diffraction study of the homobinuclear complex shows that two copper(II) ions are bridged by 4,4'-bipyridine and each copper(II) ion is trigonal-bipyramidally coordinated, with tren occupying four sites [Cu-N = 2.030(2), 2.047(2), 2.078(2), and 2.119(2) Å respectively] and a bridging 4,4'-bipyridine in the apical position. The Cu-Cu distance is 11.11 Å. In variable-temperature ESR spectra, the presence of hyperfine structure suggest that some interaction exists between the two copper(II) ions. Temperature-dependent susceptibility studies indicate that it is a weak ferromagnetic interaction with 2J = 1.23 cm-1.  相似文献   

20.
A new tetranuclear zinc(II) complex [Zn4(SO4)2(DPPZ)4(HSal)2(OH)2] 1 (DPPZ = dipyrido[3,2-a:2',3'-c]phenazine, H2Sal = salicylic acid) was prepared by using hydrothermal synthesis and characterized by elemental analysis, IR spectrum, thermal gravimetry (TG), fluorescent emission and single-crystal X-ray diffraction. Its crystal structure is of monoclinic, space group P2 1/c with a = 9.8897(8), b = 14.2506(12), c = 26.384(2) ,A, β = 94.8940(10)°, V = 3704.8(5) A3 Z = 2, C86H52N16O16S2Zn4, Mr = 1891.04, Dc = 1.695 g/cm^3, μ= 1.423 mm^-1, F(000) = 1920, GOOF = 1.039, the final R = 0.0358 and wR = 0.0872 for 6038 observed reflections with I 〉 2σ(I). In 1, "cage-like" tetranuclear clusters of [Zn4(SO4)2(DPPZ)4(HSal)2(OH)2] are further stacked through π-π interactions to generate a 3D supramolecular network.  相似文献   

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