首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
[Co2(L1)2(NCS)4]·4MeOH 1, [Co(L2)2(H2O)2](Sal)2·4H2O (Sal = salicylate) 2 were obtained from self-assembly of the cobalt salts with bis(N-benzimidazolyl)methane (L1), and bis(N-benzimidazolyl)methane (L2), and their structures were characterized by IR and X-ray diffraction analysis. Complex 1 exhibits a two-dimensional grid structure, whereas complex 2 is a coordination polymer having a one-dimensional linear chain structure. The grid in 1 lies parallel to the crystallographic ab plane and exhibits intra-grid M–M separations of 10.508 × 10.508 Å. Hydrogen bonds hold the cationic chains in 2 together leading to a three-dimensional network structure.  相似文献   

2.
Four new metal–organic supramolecular networks, namely, [Zn(H2pdc)2(H2O)2]·2H2O·bbi (1), {[Cd(Hpdc)2]·2H2O2·H2bbi}n (2), [Zn(BA)2(bbi)]n (3), and {[Cd(BA)2(bbi)]·H2O}n (4) (H3pdc = 3,5-pyrazoledicarboxylic acid, HBA = 3-hydroxybenzoic acid and bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) have been synthesized under hydrothermal conditions and characterized by IR spectra, elemental analyses, and single-crystal X-ray diffraction analyses. Compound 1 possesses zero-dimensional (0D) structure, which is finally extended into a two-dimensional (2D) supramolecular network via O–H···O and C–H···O hydrogen bonds. Complex 2 displays a 2D network structure built from Cd2+ atoms interconnected by Hpdc2? ligands. The adjacent networks are further assembled into three-dimensional (3D) supramolecular structure through O–H···O hydrogen bonds. Compounds 3 and 4 show similar one-dimensional (1D) chains, in which four-coordinated Zn(II) atoms and six-coordinated Cd(II) atoms are bridged by bbi ligands. Through O–H···O and C-H···O hydrogen bonding interactions, the 1D chains are further packed into 2D and 3D supramolecular frameworks for 3 and 4, respectively. Obviously, the structural differences among compelxes 14 are attributed to the different central metal atoms and organic ligands. In addition, compounds 14 exhibit blue fluorescent emission in the solid state at room temperature.  相似文献   

3.
Three new metal(II) complexes based on N-methylimidazole, [ML6]·(SH)2·(H2O)2, (M = Ni(II) (1), Co(II) (2), Cu(II) (3), L=N-methylimidazole), have been synthesized and characterized. The single crystal X-ray structural analyses show that complexes 1, 2, and 3 have isomorphous structures and crystallize in monoclinic system with space group P21/c. The complexes containing isolated SH? anions, which may come from the thermochemical sulfate reduction, are located in the gap with lattice water molecules and provide multiple intermolecular hydrogen bonds to form 2D layers. Topology analyses show a 2D hydrogen bond network, which can be regarded as an unprecedented trinodal (3,4,6)-connected topology with Schläfli symbol (3.4.53.6)2(3.4.5)2(32;54;64;82;93). Cyclic voltammetry and UV–vis spectra were studied.  相似文献   

4.
Three d 10 coordination polymers formulated as [Zn(L1)2(mip)] n (1), [Zn(L1)(2,6-ndc)] n (2) and [Cd(L2)0.5(bpdc)] n (3) (L1 = 1,1′-(1,3-propanediyl)bis(thiabendazole), L2 = 1,1′-(1,6-hexanediyl)bis(thiabendazole), H2mip = 5-methylisophthalic acid, 2,6-H2ndc = 2,6-naphthalenedicarboxylic acid, H2bpdc = 4,4′-biphenyldicarboxylic acid) were hydrothermally synthesized. Complexes 13 were characterized by elemental analysis, IR spectroscopy, X-ray powder diffraction analysis, and single crystal X-ray diffraction. Complexes 1 and 2 present different chain structures, both of them are extended into 2D supramolecular architectures via C–H···O hydrogen bonds, while 3 is a three-fold interpenetrating three-dimensional framework with binodal 4,4-connected mog topology. The thermal stability, UV–visible spectroscopy and luminescence properties of complexes 13 were also examined. Furthermore, complex 3 exhibits relatively positive catalytic activity towards the degradation of methyl orange in a Fenton-like process.  相似文献   

5.
Two new Zn(II) coordination polymers based on the tridentate ligand 4,6-di(1H-imidazol-1-yl)-1,3,5-triazin-2-ol (Hdit), namely, {[Zn(dit)2(H2O)2]·4H2O}n (1) and [Zn(dit)(CH3COO)]n (2), have been successfully constructed by varying the metal salts. Compound 1 shows 1D zigzag chain structure, and compound 2 is a 3D binodal (3,5)-connected architecture with {42·66·82}{42·6} topology. The photoluminescent spectra indicate that at room temperature, compounds 1 and 2 emit violet and blue luminescence, respectively.  相似文献   

6.
Two Zn(II) coordination polymers, formulated as {[Zn(L1)0.5(btc)0.5(H2O)]·H2O} n (1) and {[Zn(L2)(1,4-ndc)]·2H2O} n (2) [L1 = 1,4-bis(2-methylbenzimidazole-1-ylmethyl)benzene, L2 = 1,4-bis(2-methylbenzimidazole)butane, H4btc = butane-1,2,3,4-tetracarboxylic acid, 1,4-H2ndc = 1,4-naphthalenedicarboxylic acid] have been synthesized and structurally characterized by single crystal X-ray diffraction. Complex 1 features a 3D (3,4)-connected network with the topology of fsh-3,4-P21/c. Complex 2 is a 2D (4,4) grid with sql topology and further extends into a 3D supramolecular framework by ππ stacking interactions. In addition, the thermal stability, fluorescence, and catalytic properties of two complexes for degrading methyl orange dye in a Fenton-like process were investigated.  相似文献   

7.
Five isomorphous 3D complexes of formates, namely, {Cu(HCOO)2·4H2O} n (1), {Co(HCOO)2·2H2O} n (2), {Mn(HCOO)2·2H2O} n (3), {Co(HCOO)2·DMF·H2O} n (4), and {Mn2(HCOO)6·0.5[HN(CH3)2]} n (5), were synthesized and characterized by microanalysis. The catalytic activities of these complexes for the oxidation of phenol by H2O2 to catechol (CAT) and hydroquinone (HQ) were investigated. Complex 1 showed the best performance by exhibiting a high conversion rate of 68.02% and a high selectivity for CAT with a maximum CAT/HQ ratio of 2.74.  相似文献   

8.
Four Cd(II) coordination polymers (CPs) including [Cd(btbb)0.5(L1)] n (1), [Cd(btbb)(L2)·(H2O)1.5] n (2), [Cd(btbb)(L3)] n (3), and [Cd(btbb)(HL4)] n (4) (btbb?=?1,4-bis(thiabendazole)butane, H2L1?=?5-hydroxyisophthalic acid, H2L2?=?4,4′-biphenyldicarboxylic acid, H2L3?=?tetrabromoterephthalic acid, H3L4?=?5-nitro-1,2,3-benzenetricarboxylic acid) were prepared under hydrothermal conditions based on flexible bis(thiabendazole) ligand and different co-carboxylates. Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, X-ray powder diffraction, and thermogravimetric analyses. CP 1 exhibits a 3D 2-nodal (3,4)-connected framework with the 3,4T10 topology. CP 2 and 3 feature typical hcb layer structure, and 3 is further combined into a 3D supramolecular architecture through C–H?O hydrogen bonds. CP 4 possesses an infinite chain and further extended into 2D supramolecular network by O–H?O hydrogen-bonding interactions. The effects of the aromatic polycarboxylate co-ligands on the CPs framework have been discussed and the catalytic activities of CPs 14 for degradation of methyl orange in Fenton-like process are also investigated.  相似文献   

9.
Two new metal–organic frameworks (MOFs) based on cadmium(II) ions, 1,2-benzenedicarboxylic acid (BDC), flexible ligand 1,4-bi(1H-imidazol-1-yl)butane (BIIM), coordinated water molecules, [(BIIM)(BDC)(H2O)Cd]3n (1) and copper(II) ions, BIIM, coordinated water, free thiophene-2,5-dicarboxylate (TDC), free water, {[(BIIM)4(H2O)4Cu2]·(TDC)2·(H2O)12}n (2) are prepared and characterized by X-ray diffraction, thermal gravimetric analysis (TGA), infrared (IR) spectrum and the photoluminescence property for complex (1). The X-ray diffraction analysis reveals that the structures of complexes 1 and 2 are 2D structures through the C–H···π stacking interactions (for 1) and the BIIM bridging connections (for 2). The IR spectrum for 1 and 2 are presented in the paper, for 1, the strong peaks at 1399 and 1573 cm?1 are owing to the carboxylic CO2 ? symmetry and asymmetry stretching vibrations of BDC. The features of the IR spectrum are consistent with the single crystal structures. The TGA reveal the water is the first lost material from complex, then the ligands removed, and finally the residues of these two complexes are the metal oxide.  相似文献   

10.
Two silver(I) complexes, [Ag(dmpyz)2][Ag(barb)2] (1) and {[Ag(ppz)][Ag(barb)2]·H2O} n (2) (barb = 5,5-diethylbarbiturate, dmpyz = 2,5-dimethylpyrazine and ppz = piperazine), have been synthesized and characterized by elemental analyses, IR, thermal analysis (TG-DTA) and single-crystal X-ray diffraction. Complex 1 consists of [Ag(dmpyz)2]+ and [Ag(barb)2]? ions in which the silver(I) ions are linearly coordinated by two dmpyz or two barb ligands. These two ions are connected by strong Ag–Ag interactions (Ag–Ag = 2.896 (1) Å). Complex 2 is a 1D coordination polymer in which the silver(I) ions are bridged by the ppz ligands in a linear fashion, leading to a zigzag chain of [Ag(ppz)] n + , which interacts with the [Ag(barb)2]? units by Ag–Ag interactions of 3.183 (1) Å. The 1D chains are further assembled to form 3D networks by strong N–H···O and OW–H···O hydrogen bonds. IR spectra and TG-DTA data are in agreement with the crystal structures. The fluorescent properties of 1 were also evaluated.  相似文献   

11.
Mononuclear [Zn(FcCOO)(DTBbpy)2]ClO4.(H2O)3 (1) and dinuclear [Cd2(FcCOO)2(DTBbpy)4]ClO4·(H2O) (2), [Pb2(FcCOO)2(DTBbpy)2(H2O)2]·ClO4 (3) (FcCOO = ferrocenecarboxylate, DTBbpy = 4,4′-di-tert-butyl-bipyridyl) metal complexes have been synthesized and characterized by single crystal X-ray diffraction. It reveals that the Zn(II), Cd(II) and Pb(II) metal complexes have different coordination geometries [Zn and Pb = distorted octahedral, Cd = distorted pentagonal bipyramidal]. The compound 3 shows the hemidirected mode of coordination in the geometrical system due to the inert pair effect of the lone pair of an electron on Pb(II) metal atom. The molecules are further forms 2D & 3D framework structure via intermolecular hydrogen bonding. All the three compounds exhibit strong fluorescence emission bands in the liquid state at ambient temperature, of which the emission maxima show red-shifted and the solution-state electrochemistry of compounds 13 in CH3CN has been investigated.  相似文献   

12.
A new cadmium(II) and a new cobalt(II) coordination complexes [Cd5(BTB)4(HL)2]·2H2O (1) and [Co(HBTB)(L)]·2H2O (2) [H3BTB?=?1,3,5-tri(4-carboxylphenyl)benzene, L?=?N,N′-bis(3-pyridyl)octandiamide] were prepared under the solvothermal conditions by the assembly of cadmium(II)/cobalt(II) chloride, the flexible bis(pyridyl)-bis(amide) ligand L and the aromatic tricarboxylic acid H3BTB. The structures of complexes 12 have been characterized by X-ray single crystal diffraction analyses, infrared spectroscopy (IR), powder X-ray diffraction (PXRD) and thermogravimetric (TG) analyses. Complex 1 is a 3D metal–organic network with the penta-nodal (2,4,4,5,6)-connected {4·63·8·10}2{42·65·83}2{43·63}2{46·89}{6}2 topology constructed from the 3D [Cd5(BTB)4]n2n? coordiantion framework and the protonated HL ligands. Complex 2 displays a binodal (4,4)-connected {64·8·10}{6} topological 2D layered architecture based on the 1D [Co(HBTB)]n chains and the 1D [CoL]n chains, which are further linked by hydrogen bonding interactions to form a 3D supramolecular network. Moreover, the fluorescent properties of the cadmium(II) complex and the dyes adsorption performances of complexes 12 have been studied.  相似文献   

13.
The new ionic heterotrimetallic unsymmetrically-substituted Schiff base complex [Ni{(η 5-Cp)Fe(η 5-C5H4)-C(=O)CH=C(4-HO-C6H4)NCH2CH2N=CH-(2-O-(η 6-C6H4)Ru(η 5-Cp*)}][PF6] (3; Cp = C5H5 and Cp* = C5(CH3)5) was prepared in 86% yield by a one-pot procedure by mixing equimolar amounts of 4-hydroxyphenyl functionalized ferrocenylenaminone 1, the organometallic aldehyde [(η 5-Cp*)Ru(η 6-2-HO-C6H4CHO)][PF6] (2) and nickel(II) acetate tetrahydrate in refluxing ethanol for 2 h. Its corresponding side-chain metallopolymer 4 was synthesized by reacting the organometallic-inorganic hybrid 3 with polyacrylic acid (DP = 25) in DMF at 110 °C for 48 h with an equimolar quantity of N,N′-dicyclohexylcarbodiimide and a catalytic amount of 4-dimethylaminopyridine. The new complex 3 was characterized by FT-IR and multidimensional NMR spectroscopy, elemental analysis and mass spectrometry. Single crystal X-ray diffraction analysis of 3 showed that the ferrocenyl and [(η 5-Cp*)Ru]+ units exhibit an anti-conformation and are almost coplanar with the unsymmetrical Schiff base complex fragment, while the 4-HO-C6H4 plane is almost perpendicular. The four-coordinate NiII metal ion adopts a square planar geometry, with two nitrogen and two oxygen donor atoms that are mutually trans. Size-Exclusion Chromatography established that metallopolymer 4 is formed of approximately three pendant ionic trimetallic units, while Differential Scanning Calorimetry and Thermal Gravimetric Analysis indicated that 3 and 4 are thermally stable with decomposition temperatures that exceed or border to 250 °C. Harmonic Light Scattering measurements at 1.91 µm incident wavelength showed that compounds 3 and 4 exhibit rather high second-order nonlinear responses, with hyperpolarizability β 1.91 values strongly increasing on passing from the monomeric unit 3 to its metallopolymeric counterpart 4.  相似文献   

14.
Two palladium(II) nitroaryl complexes trans-[bromo(p-nitrophenyl)bis(triphenylphosphine)palladium(II)] 1 and trans-[bromo(2,4-dinitrophenyl)bis(triphenylphosphine)palladium(II)] 2 have been synthesized. The complexes were characterized by FTIR and NMR (1H, 13C and 31P) spectroscopy and elemental analysis. The molecular structure of complex 2, as confirmed by X-ray crystallography, reveals that the Pd atom and its neighboring groups (two PPh3, Br and phenylene group) lie in a slightly distorted square plane. In the UV–Vis spectra of the complexes 1 and 2, the palladium to aryl charge transfer bands were observed. The emission peaks from the singlet excited states (S1  S0) were observed in the photoluminescence spectra of the complexes. The thermal stability of the complexes has been studied by thermal gravimetric analysis (TGA). TGA data showed that both complexes are thermally stable up to 200 °C, and complex 1 is more stable than 2. The catalytic efficiency of the new palladium(II) complexes was studied as demonstrated using the Sonogashira coupling reactions with good yields. The experimental results suggest that the Sonogashira coupling reactions can be performed at moderate temperature (50 °C) using these new palladium(II) complexes as catalysts.  相似文献   

15.
Employing tetracarboxylate and imidazole mixed ligands to react with different transition meat salts afford two new 3D coordination polymers, {[Zn2(BPTC)(BBI)2]·(H2O)3·DMSO}n (1) and {[Cd2(BPTC)(BBI)2]·H2O}n (2) (H4BPTC?=?biphenyl-3,3′,4,4′-tetracarboxylic acid, BBI?=?1,1′-(1,4-butanediyl)bis(imidazole)). Both these two coordination polymers are 4-connected network topologies. Compound 1 features a unprecedented 3-nodal (4,4,4)-connected network topology with the point symbol {64·82}, and 2 displays a (4,4)-connected binodal network bearing new topology with the point symbol of {72·84}2{73·83}. Additionally, thermal stability and photoluminescence properties of 1 and 2 were investigated.  相似文献   

16.
The ionic salt [2(C5H6N2Cl)+], [CuCl4]2? complex of copper(II) has been synthesized and characterized. The X-ray diffraction analysis with a single crystal of this compound showed that the title compound (4-amino-2-chloropyridinium)2CuCl4 [(CAP)2CuCl4], crystallized at room temperature in the monoclinic system, space group C2/c (N°.15) and the following : a = 16.0064 (2) Å; b = 7.7964 (10) Å; c = 14.7240 (2) Å; β = 102.497 (10)°; V = 1793.91 (4) Å3 and Z = 4. The structure was solved by using 1,589 independent reflections down to R value of 0.021. The unit cell is made up of tetrachlorocuprate(II) anions and 4-amino-2-chloropyridinium cations linked together by an extensive hydrogen bond network of types N–H···Cl (N: pyridinium) and N–H···Cl (N: amine), and cation-lone pair of nitrogen element interactions. Solid state NMR spectra showed one and five isotropic resonances, 63Cu and 13C, respectively, confirming the solid state structure determined by X-ray diffraction. Impedance spectroscopy study, reported for single crystal, revealed that the conduction in the material was due to a hopping process. This work aims to reveal the thermal properties of a new copper(II) based organic–inorganic hybrid and the conductivity properties that these compounds exhibit.  相似文献   

17.
A microporous lead–organic framework {[Pb4(µ8-MTB)2(H2O)4]·5DMF·H2O}n (MTB?=?methanetetrabenzoate, DMF?=?N,N′-dimethylformamide) was synthesized and studied as a catalyst in Knoevenagel condensation reactions. The framework is built from tetranuclear [Pb4(µ3-COO)(µ2-COO)6(COO)(H2O)4] clusters and exhibits a 3D structure, with repeated 1D jar-like cavities with sizes about 14.98?×?7.88 and 14.98?×?13.17 Å2 and BET specific surface area of 980 m2 g?1. To obtain open framework with unsaturated Pb(II) sites needed for catalysis, the thermal activation of the solvent exchanged sample was performed (DMF was exchanged by EtOH). The activated compound was tested in Knoevenagel condensation of bulky aldehydes and active methylene compounds at different temperatures. Excellent catalytic conversion and selectivity in condensation of small-sized aldehydes with malononitrile was observed, which indicates that the opened Pb(II) sites play a significant role in the heterogeneous catalytic process. Leaching test confirmed the stability of the catalyst in catalytic reactions. Moreover, the compound displayed good recyclability after several reuses without significant decrease in the original catalytic activity.

Graphical Abstract

Novel Pb(II) metal–organic framework was tested in Knoevenagel condensation. The catalyst showed excellent catalytic conversion, selectivity and recyclability. Aldehydes with lower kinetic diameter demonstrated high conversions and yields. Catalyst is less efficient for condensation of larger aromatic aldehydes.
  相似文献   

18.
Nanosized powders of orthophosphates in the LaPO4–HoPO4–H2O system have been synthesized to determine the mutual solubility of LaPO4 · nH2O and HoPO4 · nH2O initial components and to obtain ceramic matrices by sintering them. Formation of hexagonal, monoclinic or tetragonal solid solutions was revealed, and their limits and thermal stability were determined. A series of limited hexagonal LaPO4 · nH2O-based solid solutions was observed within the 0 ≤ x ≤ 0.6 concentration range up to 600°C. Further they transformed to monoclinic LaPO4-based form within the 0 ≤ x ≤ 0.3 concentration range. Solubility of LaPO4 · nH2O and LaPO4 in tetragonal HoPO4nH2O) is lower (≤10 mol %). Specific surface area of La1–xHoxPO4 · nH2O powders was in the range of 90.5–165.0 m2/g depending on x. Leaching rate of La3+ and Ho3+ from La1–xHoxPO4 matrices in nitric acid solution (pH 1–2) was determined to be 10–5–10–2 g/(cm2 day) for both ions.  相似文献   

19.
Three amidosulfobetaine surfactants were synthesized namely: 3-(N-pentadecanamidopropyl-N,N-dimethyl ammonium) propanesulfonate (2a); 3-(N-heptadecanamidopropyl-N,N-dimethyl ammonium) propanesulfonate (2b), and 3-(N-nonadecanamidopropyl-N,N-dimethyl ammonium) propanesulfonate (2c). These surfactants were prepared by direct amidation of commercially available fatty acids with 3-(dimethylamino)-1-propylamine and subsequent reaction with 1,3-propanesultone to obtain quaternary ammonium salts. The synthesized surfactants were characterized by IR, NMR and mass spectrometry. Thermogravimetric analysis (TGA) results showed that the synthesized surfactants have excellent thermal stability with no major thermal degradation below 300 °C. The critical micelle concentration (CMC) values of the surfactants 2a and 2b were found to be 2.2 × 10?4 and 1.04 × 10?4 mol/L, and the corresponding surface tension (γCMC) values were 33.14 and 34.89 mN m?1, respectively. The surfactants exhibit excellent surface properties, which are comparable with conventional surfactants. The intrinsic viscosity of surfactant (2b) was studied at various temperatures and concentrations of multi-component brine solution. The plot of natural logarithm of relative viscosity versus surfactant concentration obtained from Higiro et al. model best fit the surfactant behavior. Due to good salt resistance, excellent surface properties and thermal stability, the synthesized surfactant has potential to be used in various oil field applications such as enhanced oil recovery, fracturing, acid diversion, and well stimulation.  相似文献   

20.
In the superbasic medium DMSO-KOH, bis(3,3-diethoxycarbonyl-1-pyrazolyl)methane (L) was synthesized. Besides, the single crystal of L has been obtained. Meanwhile, one novel coordination polymers, [Ag(L)(NO3)] n (1) was successfully prepared. The single X-ray diffraction data reveal that L crystallized in the P-1 space group. Novel bis(pyrazolyl)methane derivative ligand, L acts as multidentate ligands to coordinate with Ag ion to form a six-membered boat conformation. And furthermore the nitrate groups bridge each Ag(I) to construct a zigzag chain. The fluorescent properties of the complex were examined in solution and compared with the ligand. In order to investigate the intermolecular interactions, we also studied Hirshfeld surface analysis of ligand and the complex. The Hirshfeld surface analysis reveals that the main intermolecular interactions are H···H and O···H/H···O interactions which comprise 23.9 and 33.8 % of the total Hirshfeld surface area.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号