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1.
水热条件下,合成了2个三维配位聚合物{[Zn4(L)2o-bix)2]·2H2O}n1),{[Co4(L)2o-bix)2]·2H2O}n2)(H4L=5,5’-亚甲基二间苯二甲酸,o-bix=1,2-双(咪唑基-1-甲基)-苯),并通过红外、热重和X-射线单晶衍射进行了表征。X-射线衍射结果表明这2个化合物具有相似的结构。在1个不对称单元中,化合物包含2个不同配位环境的金属离子,1个L4-配体,1个o-bix分子以及1个游离的溶剂水分子。中心金属离子分别采用畸变的四面体和四方锥构型,形成两类双核单元,然后通过全部脱质子的L4-形成3D孔洞结构,o-bix配体通过连接两类双核金属原子填充于孔洞之中,形成3D紧密堆积结构。对化合物的红外和热重性质进行了表征。  相似文献   

2.
New complexes cis-[M(CO)4-DABRd] (M = Cr(I), Mo(II) and fac-[M(CO)3-SAT] (M = Cr(III), Mo(IV)) have been synthesized by the photochemical reactions of cis-[(η4-NBD)M(CO)4] (NBD is norbornadiene; M=Cr, Mo) with 5-(4-dimethylaminobenzylidene) rhodanine (DABRd) and salicylidene-3-amino-1,2,4-triazole (SAT) ligands and characterized by elemental analysis, FT-IR and 1H NMR spectroscopy, and mass spectrometry. The spectroscopic studies show that the DABRd ligand acts as a bidentate ligand coordinating via both NH-(S)C=S sulfur donor atoms in I and II and SAT ligand behaves as a tridentate ligand coordinating via its all imine nitrogen-C=N-donor atoms in III and IV to the metal center. The article was submitted by the authors in English.  相似文献   

3.
Derivatives of bis(phenylhydrazono-1H-tetrazol-5-yl-acetonitriles) with oxygen and sulphur atoms in the structure of aliphatic chains were successfully synthesised. The correlation between the ligand structure and its complexation properties was investigated by absorption spectroscopy. The formation of complexes of presented compounds with metal cations (Cu2+, Ni2+, Zn2+, Co2+, Fe2+ and Pb2+) was studied. Ligands 58 were additionally applied as ion carriers in ion-selective membrane electrodes. Membranes of ion-selective electrodes doped with these ligands are selective to Cu2+ and Pb2+ cations.  相似文献   

4.
The visible light irradiation of the [(η5-C6H7)Fe(η-C6H6)]+ cation (1) in acetonitrile resulted in the substitution of the benzene ligand to form the labile acetonitrile species [(η5-C6H7)Fe(MeCN)3]+ (2). The reaction of 1 with ButNC in MeCN produced the stable isonitrile complex [(η5-C6H7)Fe(ButNC)3]+ (3). The photochemical reaction of cation 1 with pentaphosphaferrocene Cp*Fe(η-cyclo-P5) afforded the triple-decker cation with the bridging pentaphospholyl ligand, [(η5-C6H7)Fe(μ-η:η-cyclo-P5)FeCp*]+ (4). The latter complex was also synthesized by the reaction of cation 2 with Cp*Fe(η-cyclo-P5). The structure of the complex [3]PF6 was established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2088–2091, November, 2007.  相似文献   

5.
The chiral complexes [PdL1Cl2] (I) and [PdL2Cl2] (II) (where L1 and L2 are hydroxypyrazolylquinoline and pyrazolylquinoline, respectively, based on the monoterpenoid (+)-3-carene) were obtained and examined using X-ray diffraction. The crystal structures of complexes I and II are built from mononuclear acentric molecules. The Pd2+ ions coordinate two N atoms of the chelating bidentate ligand L1 or L2 and two Cl atoms. The coordination polyhedron Cl2N2 is a square distorted in a tetrahedral manner. In structure I, adjacent molecules are linked by intermolecular contacts and hydrogen bonds Cl···H-O, which gives rise to chains aligned with the axis x. In structure II, contacts that are substantially shorter than the van der Waals interactions were not detected.  相似文献   

6.
Two Cd(II) coordination polymers constructed from tris(p-carboxylphenyl)phosphine oxide (H3TPO), [Cd(HTPO)(1,4-bix)·3H2O]n (1) and [Cd2(HTPO)(HBPO)(H2O)2]n (2) (1,4-bix = 1,4-bis(imidazol-1-ylmethyl)benzene, H3BPO = bis(4-carboxylphenyl)phosphinic acid), were synthesized and identified by IR, elemental analysis, and single-crystal X-ray diffraction analysis. The 1,4-bix ligand leads to 1 as a ladder-like 1D chain structure. In 2, adjacent Cd2 units are bridged by HBPO2– and HTPO2– ligands to form a 3D structure. The H3BPO ligand is formed from the in situ reaction of H3TPO. It is the first example from hydrated Cd(II) salt promoting partial hydrolysis of a phosphine oxide ligand. The thermal behavior and solid-state photoluminescence properties correlated with the corresponding structural features were investigated.  相似文献   

7.
以3,5-二(苯并咪唑基)吡啶(L)、间苯二甲酸(m-H2BDC)、4-羧基肉桂酸(H2CCA)、ZnSO4·7H2O和Cd(NO3)2·4H2O为原料,使用溶剂热方法合成了两个配位聚合物[Zn(L)(m-BDC)](1)和[Cd(L)(CCA)]·2H2O(2),利用红外、元素分析、热重分析和X-射线粉末衍射对其进行了表征,利用X-射线单晶衍射对结构进行了测定,并研究了配合物的荧光性质。在配合物1中,L与金属离子连接形成了一维(1D)链结构,而间苯二甲酸根离子与金属离子构成了一个M2(m-BDC)2(M=金属离子)的单元。一维链之间通过M2(m-BDC)2单元连接形成二维网状(2D)结构。在配合物2中,和配合物1类似,L与金属离子连接形成一维链,但与1不同的是羧酸配体与金属离子配位也构成了一维链结构,两种一维链通过配位作用连接构成二维结构。  相似文献   

8.
选择刚性的1,2,4,5-均苯四甲酸(H4L)为主配体,以1,3-双(1H-咪唑-1-基甲基)苯(1,3-bib)为辅助配体,在水热条件下,与过渡金属离子Cd2+配位合成了配合物[Cd(L)0.5(1,3-bib)(H2O)]·H2O(1)。利用元素分析、红外光谱、X射线单晶衍射、热重和X射线粉末衍射对其结构进行了表征,并研究了化合物的荧光性质。结果表明:配合物1属正交晶系,空间群Pbca,a=0.857 08(4)nm,b=1.912 23(10)nm,c=2.451 60(12)nm。配合物1中Cd2+与L4-配体的羧基通过双齿螯合配位,通过1,3-bib连接形成三维网状结构。配合物1具有较强的荧光,其对丙酮溶剂、MnO4-、Hg2+离子有一定的荧光猝灭。  相似文献   

9.
The in situ ligand 2,3-pyrazinedicarboxylic acid (2,3-H2pzdc) mixed with 1,1′-(1,4-butanediyl)bis(benzimidazole) (bbbi) is used to form two coordination polymers ([Cd(2,3-pzdc)(bbbi)] (1) and [Cd2Cl3(2-pzc)(bbbi)2] (2)) under hydrothermal conditions. Complex 1 was obtained in the absence of in situ reaction and 2 was synthesized with 2,3-H2pzdc in situ generating 2-pyrazinecarboxylate (2-pzc?). The structural details reveal that 1 has a 3D framework with dia topology, and 2 is a 2D layer structure and develops a 3D supramolecular structure via strong π?π stacking interactions. The ligand effects were compared for the two frameworks. In addition, fluorescence properties and thermal stabilities of 1 and 2 in the solid were studied.  相似文献   

10.
水热条件下,合成了2个三维配位聚合物{[Zn4(L)2(o-bix)2]·2H2O}n(1),{[Co4(L)2(o-bix)2]·2H2O}n(2)(H4L=5,5′-亚甲基二间苯二甲酸,o-bix=1,2-双(咪唑基-1-甲基)苯),并通过红外、热重和X-射线单晶衍射进行了表征。X-射线衍射结果表明这2个化合物具有相似的结构。在1个不对称单元中,化合物包含2个不同配位环境的金属离子,1个L4-配体,1个o-bix分子以及1个游离的溶剂水分子。中心金属离子分别采用畸变的四面体和四方锥构型,形成两类双核单元,然后通过全部脱质子的L4-形成3D孔洞结构,o-bix配体通过连接两类双核金属原子填充于孔洞之中,形成3D紧密堆积结构。对化合物的红外和热重性质进行了表征。  相似文献   

11.
选择刚性的1,2,4,5-均苯四甲酸(H4L)为主配体,以1,3-双(1H-咪唑-1-基甲基)苯(1,3-bib)为辅助配体,在水热条件下,与过渡金属离子Cd2+配位合成了配合物[Cd(L)0.5(1,3-bib)(H2O)]·H2O (1).利用元素分析、红外光谱、X射线单晶衍射、热重和X射线粉末衍射对其结构进行了表...  相似文献   

12.
以3,5-二(苯并咪唑基)吡啶(L)、间苯二甲酸(m-H2BDC)、4-羧基肉桂酸(H2CCA)、ZnSO4·7H2O和Cd(NO3)2·4H2O为原料,使用溶剂热方法合成了两个配位聚合物[Zn(L)(m-BDC)] (1)和[Cd(L)(CCA)]·2H2O (2),利用红外、元素分析、热重分析和X-射线粉末衍射对其进行了表征,利用X-射线单晶衍射对结构进行了测定,并研究了配合物的荧光性质。在配合物1中,L与金属离子连接形成了一维(1D)链结构,而间苯二甲根离子与金属离子构成了一个M2(m-BDC)2(M=金属离子)的单元。一维链之间通过M2(m-BDC)2单元连接形成二维网状(2D)结构。在配合物2中,和配合物1类似,L与金属离子连接形成一维链,但与1不同的是羧酸配体与金属离子配位也构成了一维链结构,两种一维链通过配位作用连接构成二维结构。  相似文献   

13.
Starting from 4-chloro-3,5-dinitrobenzoic acid 1, compounds 210 (N-alkoxy-3,5-dinitro-4-aminobenzoic acid esters where alkoxy stands for methoxy, carboxymethoxy, triphenylmethoxy, or corresponding amides) have been obtained, from which compounds 35 and 710 are new, and for the known compounds 2 and 6 the synthetic procedure has been improved. The new derivatives have been characterized by appropriate means (IR, UV–Vis, 1H- and 13C-NMR, fluorescence) and their properties were studied. Thus, depending on their structure, the compounds have acid properties, fluorescence and complexing properties with alkaline cations.  相似文献   

14.
Two cobalt(II) complexes based on 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol (HOBPT), [Co3(OBPT)(μ3?OH)(SO4)2(H2O)3]·2H2O (1) and [Co(OBPT)2]·2H2O (2) were obtained. Single-crystal X-ray diffraction analyses indicate that 1 is a two-dimensional (2D) structure and the ligand adopts mono/bis-bidentate coordination; this coordination mode of this ligand was never found before. Magnetic properties of 1 have been studied, showing that 1 is a spin canted belt. Much different from 1, 2 is a discrete structure with tridentate ligand with its hydroxyl group deprotonated but uncoordinated. Lattice water molecules in 2 link to four-membered water clusters, which linked the [Co(OBPT)2] to 1-D chains along the b axis.  相似文献   

15.
Abstract

The synthesis, spectral characterization, crystal structure and properties of [Ba(H2O)2(NMF)2(4-nba)2], 1 (NMF = N-methylformamide; 4-nba = 4-nitrobenzoate), are reported. 1H and 13C NMR spectral data reveal the presence of NMF in 1. A strong band at 1660?cm?1 in the infrared spectrum indicates the binding of amide oxygen to Ba(II) which is confirmed by the single crystal structure. The unique Ba(II) in 1 situated on a mirror plane exhibits nine coordination and is bonded to two symmetry related monodentate terminal NMF ligands via the amide oxygen, and a terminal aqua ligand. The μ2-monoatomic bridging binding mode of each of a crystallographically independent 4-nba ligand and a unique water ligand link the Ba(II) cations into an infinite chain extending along a, leading to the formation of a 1D coordination polymer with Ba···Ba separations of 4.2522(3) Å. In the chain, the {BaO9} polyhedra are linked in a face sharing fashion. Thermal decomposition of 1 results in the formation of BaCO3 residue. A comparative study of the structural chemistry of several barium coordination polymers is described.  相似文献   

16.
A series of pyrrole‐containing diarylphosphine and diarylphosphine oxide ligands were prepared. The catalytic activity of the corresponding in‐situ‐generated chromium catalysts was investigated during selective ethylene oligomerization reactions. Variations in the ligand system were introduced by modifying the diarylphosphine and pyrrole moieties that affect the steric and electronic properties. Minor changes in the ligand structure and the composition of activators significantly changed the catalytic activity, selectivity toward linear alpha‐olefins (LAO) versus polyethylene (PE), and the distribution of oligomeric products. The presence of trifluoromethyl groups on the diphenyl rings in ligand 3 promoted oxidation to form the corresponding phosphine oxide structure, 3o , which dramatically enhanced the catalytic activity of ethylene trimerization. The in‐situ‐generated chromium complex based on 3o activated by DMAO (dry methylaluminoxane)/TIBA (triisobutylaluminum) was used to achieve activity of about 1250 g (mmol of Cr)−1 h−1 with 98.5 mol % 1‐hexene, along with a negligible amount of PE side product. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 444–450  相似文献   

17.
Polycyclic azoniahetarenes were employed to determine the effect of the structure of unsubstituted polyaromatic ligands on their quadruplex‐DNA binding properties. The interactions of three isomeric diazoniadibenzo[b,k]chrysenes ( 4 a – c ), diazoniapentaphene ( 5 ), diazoniaanthra[1,2‐a]anthracene ( 6 ), and tetraazoniapentapheno[6,7‐h]pentaphene ( 3 ) with quadruplex DNA were examined by DNA melting studies (FRET melting) and fluorimetric titrations. In general, penta‐ and hexacyclic azoniahetarenes bind to quadruplex DNA (Kb≈106 M ?1) even in the absence of additional functional side chains. The binding modes of 4 a – c and 3 were studied in more detail by ligand displacement experiments, isothermal titration calorimetry, and CD and NMR spectroscopy. All experimental data indicate that terminal π stacking of the diazoniachrysenes to the quadruplex is the major binding mode; however, because of different electron distributions of the π systems of each isomer, these ligands align differently in the binding site to achieve ideal binding interactions. It is proposed that tetraazonia ligand 3 binds to the quadruplex by terminal stacking with a small portion of its π system, whereas a significant part of the bulky ligand most likely points outside the quadruplex structure, and is thus partially placed in the grooves. Notably, 3 and the known tetracationic porphyrin TMPyP4 exhibit almost the same binding properties towards quadruplex DNA, with 3 being more selective for quadruplex than for duplex DNA. Overall, studies on azonia‐type hetarenes enable understanding of some parameters that govern the quadruplex‐binding properties of parent ligand systems. Since unsubstituted ligands were employed in this study, complementary and cooperative effects of additional substituents, which may interfere with the ligand properties, were eliminated.  相似文献   

18.
The synthesis of a new vic-dioxime ligand, N,N2-dihydroxy-O 1,O 2-bis(4-methyl-2-oxo-2H-chromen-7-yl)oxalimidamid (LH2) (1), bearing functional coumarins and its soluble mono- {Ni(II), Cu(II), Co(II)} and dinuclear {UO2(II)} complexes are presented. The fluorescence properties due to the 7-hydroxy-4-methylcoumarin fluorophore, which is conjugated with vic-dioxime that functions as the MN4 core of 1 and its complexes, are also reported. The formation of coordination complexes resulted in the blue shift in excitation spectrum and fluorescence quenching of 1. Both mononuclear {(LH)2M, M=Ni(II), Cu(II), and Co(II)} and homodinuclear {(LH)2(UO2)2(OH)2)} complexes have been obtained with metal?:?ligand ratios of 1?:?2 and 2?:?2, respectively. The characterizations of the new compounds were made by elemental analysis, 1H-NMR, FT-IR, UV-Vis, and LCMS data. Redox behavior of 1, involving oxime and coumarin moieties, and its complexes with Ni(II), Cu(II), Co(II) and UO2(II) were investigated by cyclic voltammetry. The comparison of the electrochemical behavior of 1 with its complexes enabled us to identify metal-, oxime- and coumarin-based signals.  相似文献   

19.
Cobalt and nickel coordination polymers containing the conformationally flexible 3-pyridylnicotinamide (3-pna) ligand and a five-membered ring-based dicarboxylate ligand have been prepared and structurally characterized via single-crystal X-ray diffraction. [Co(tpdc)(3-pna)]n (1) was prepared using 2,5-thiophenedicarboxylic acid (H2tpdc). This material shows a 2-D layer structure containing {Co2(OCO)2} dimers linked by tpdc and 3-pna ligands. Compound 1 manifests an underlying 3,5-connected (426)(42678) 3,5L2 topology. The isostructural pair of solids [Co(D-cam)(3-pna)(H2O)2]n (2) and [Ni(D-cam)(3-pna)(H2O)2]n (3) was obtained from the chiral D-camphorate (D-cam) ligand. These two materials possess acentric ribbon coordination polymer motifs. Compound 1 manifests antiferromagnetic coupling concomitant with Kramers doublet formation. Thermal properties of these materials are also discussed.  相似文献   

20.
由水热法得到2个新颖配位聚合物[Cd(2-mba)(bimb)]n(1)和[Pb(2-sb)]n(2)(H2(2-mba)=2-巯基苯甲酸, bimb=4,4-双(1-咪唑基)联苯,sb2-=2-亚磺基苯甲酸酯) 通过元素分析、红外光谱、X射线粉末衍射和单晶衍射对其进行了表征。配合物1为二维网状结构,由一维的[Cd(2-mba)]n链与bimb连接形成。在配合物2中配体2-巯基苯甲酸在溶剂热的条件下通过原位反应被氧化成2-亚磺基苯甲酸酯,其结构为一种由配体2-亚磺基苯甲酸酯中的羧基与亚磺基桥联金属铅离子形成的二维(4,4)连接的层状结构。此外,2个配合物展示了良好的热稳定性和光致发光性能。  相似文献   

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