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1.
1 INTRODUCTION It is well known that the bi-functional 4,4?-bi- pyridine (4,4?-bpy) has the ability to act as a rigid, rod-like organic building block in the self-assembly of coordination frameworks. Many researches have also been done on the metal oxalate compounds. The remarkable coordination abilities of oxalate and 4,4?- bpy ligands are applied to design and synthesize new polymeric coordination complexes[1~4] containing mixed bridging ligands. Manganese is one of the several first-r…  相似文献   

2.
1 INTRODUCTION In the last few years, much attention has been paid to the molecular structure and biological activity of coordinated complexes in inorganic chemistry field. Ni(Ⅱ) is one of the commonest transition metals with two coordination numbers (4 and 6)[1~3]. Ge- nerally speaking, Ni(Ⅱ) coordination mode depends on the structure of ligand, solvent and reaction con- ditions, among which ligand plays a decisive role and determines not only the molecular structure of the complex bu…  相似文献   

3.
1 INTRODUCTION The increasing interest in inorganic-organic hybrid framework assemblies has resulted in a great number of research efforts focused on the develop- ment of new functional materials possessing various potential applications on catalysis, electrical conduc- tivity and magnetism[1~4]. In recent years, the inter- action of H2pdc with several metal ions has been extensively studied[5, 6] due to its unique ability to form stable chelates in diverse coordination modes such as bid…  相似文献   

4.
1 INTRODUCTION The research on azide-bridged transition metal complexes has attracted great interest in the past decade due to their magnetic properties and potential applications[1~2]. A number of azide- bridged complexes with the end-to-end coordination mode affording antiferromagnetic exchange interactions and the end-on coordination mode showing ferromagnetic exchange interactions have been reported in recent years[3]. In the synthesis of azide bridged cobalt complexes, it was found …  相似文献   

5.
1 INTRODUCTION The coordination chemistry of tin or organotin toward poly(pyrazol-1-yl)borate ligands has been extensively investigated in recent years owing to the antitumor activity of some related organotin derivatives containing N-donor ligands. A number of organotin(Ⅳ) complexes containing poly(pyrazol- 1-yl)borate ligands have been synthesized and characterized[1~3], some of which have also shown interesting structural characteristics and reactivities[4~6]. Recently, poly(pyrazol…  相似文献   

6.
1 INTRODUCTION Bis(pyrazol-1-yl)methane has been one of the po- pular polydentate nitrogen donor ligands due to its strong chelating coordination to transition metal ions as capping ligand. Coordination behavior of the li- gand is able to yield stable M-N-N-C-N-N six-mem- bered boat conformation[1, 2]. The complexes con- taining bdpm ligand have been widely synthesized and characterized in recent years, and exhibit the striking properties in catalysis, magnetism and so on[3-10]. For exa…  相似文献   

7.
IntroductionIn the last few years there has been a rapidlygrowing number of reports in the literature ad-dressing the use of polyoxometalates as antiviraland anti- tumor agents[1— 4] . Polyoxometalates areexcellent molecular acceptors,a number of organicsubstrates containing N,S and O atoms are excel-lent molecular donors,by means of molecular as-semblies,they can form novel compounds at roomtemperature[5— 7] .As is known,amino acids are thebasic units of biological molecules and interactio…  相似文献   

8.
1 INTRODUCTION Manganese has been implicated as an essential part of the active center in various manganese enzymes. Various nuclearities have been observed from mononuclear atom in superoxide dismutase [1] to the tetranuclear atom of oxygen evolution in photosystem II[2]. The manganese active centers in biological systems are surrounded by O and N coordination sphere[3, 4]. Synthetic efforts have produced a great variety of Mn clusters with varying nuclearity and oxidation states. Si…  相似文献   

9.
0IntroductionThe solid-state chemistry of manganese!car-boxylate coordination polymers has received growingattention over the past few years,owing to their fasci-nating network topologies and potential application inthe field of molecular magnetism and bi…  相似文献   

10.
Synthesis and Crystal Structure of (C_6N_3H_(18))_2Ti_4O_4(C_2O_4)_7·4H_2O   总被引:1,自引:1,他引:0  
1 INTRODUCTION The open-framework inorganic materials have been synthesized before the early 1980s[1]. Parti- cularly, metal phosphates have been investigated widely during the past few years[2, 3]. In recent years, considerable efforts have been devote…  相似文献   

11.
1 INTRODUCTION Coordination chemistry has been playing an important role in nonlinear optical (NLO) materi- als [1~3] in recent years. It has been found that tetrahedral or square pyramidal molecular configurations are useful for designing transparent second-harmonic generation (SHG) materials from coordination compounds[4]. It has also been reported that the pyridyl-based metal complexes can exhibit SHG effects[5]. Recently, we have successfully synthesized a new coordination compoun…  相似文献   

12.
1 INTRODUCTION Synthesis of transition-metal complexes with Schiff-base has been a subject of considerable im- portance[1, 2]. These complexes are not only good coordination agents for Schiff-base, but also good bactericide and antitumour agent[3, 4]. A number of hydroxypyridinones are nontoxic compounds that have been applied in bioinorganic chemistry over many years[5], and their iron(III) complexes have been assessed for the amelioration of anaemia[6]. They have also been examined …  相似文献   

13.
1 INTRODUCTION There is increasing interest in the study of orga-notin carboxylic ester compounds due to their insec-ticidal, fungicidal and antibiotic activities[1, as well 2]as structure diversity. In recent years many organo-tin carboxylic ester compounds with good biologi-cal activity have been synthesized[3, . Previous stu- 4]dies show that the coordination geometry of centralatom Sn …  相似文献   

14.
1 INTRODUCTION The researches on 4,4?-bpy bridged transition me-tal coordination polymers (4,4?-bpy = 4,4?-bipyri-dine) assembled through covalent or hydrogen bondshave attracted great interest in the past decade due toits structural diversities and potential applications[1~5].So far a number of one-, two- and three-dimensio-nal coordination polymers containing N,N?-bidentatespacers with infinite chain[6, , diamond[4], rectangle[8~11], 7]T-shape[5, 12], ladder[13~15], octahedron[16] an…  相似文献   

15.
1 INTRODUCTION The coordination chemistry of Pd(Ⅱ) com- plexes with didentate nitrogen coordination ligands has been extensively studied for a few decades[1]. Pd(Ⅱ) trends to bond to the didentate nitrogen in cis-mode and such complexes have potential usage in the emerging area of self-assembly[2]. We will report herein the synthesis and crystal structure of a cis-coordinated mononuclear Pd(Ⅱ) complex with one 1,10-phenanthroline and two THF as ligands, 1. 2 EXPERIMENTAL 2. …  相似文献   

16.
The electrical conductive molecular crystals (Me3NEt)[Pd(dmit)2]2 and (NEt4)[Pd (dmit)2]2 (dmit = 4,5-dimercapto-1,3-dithiole-2-thione) have been prepared, and their crystal structures and conductivity-temperature curves have been determined. The fact that the conductivity at room temperature of (Me3NEt)[Pd(dmit)2]2 (a = 58 Ω· cm-1) is much higher than that of (NEt4)-[Pd(dmit)2]2(cr= 2.2 Q~1 ?cm'1) has been rationally explained by the results of energy band calculations. (MeNEt3)[Pd(dmit)2]2 belongs to monoclinic system, P21/m space group and (NEt4)[Pd (dmit)2]2 belongs to triclinic system, P1 space group. The structural conducting component of the crystals is the planar coordinative anion [Pd(dmit)2]05- which forms the face-to-face dimmer [Pd(dmit)2]2-. These dimers have been further constructed to be a kind of two-dimensional (2-D)conductive molecular sheet by means of S…S intermolecular interactions. The tiny difference of the above 2-D molecular sheets of the two title crystals has resulted in one  相似文献   

17.
1 INTRODUCTION [(phen)2Pb(NCS)(O2NO)][14] and Pb(phen)3 (SCN)2 .[15] We report and compare herein the synthesis and The coordination chemistry of lead(II) with N structural characterization of a novel lead thiocya-donor ligands has been widely investigated in the nate adduct with unusual four coordination Pb(II).past decade and frequently discussed with regard tothe stereochemical activity of valence shell lone elec- 2 EXPERIMENTALtron pairs[1~5]. The building of new molecule…  相似文献   

18.
Over the past few years, extensive research has been focused on the preparation, purification, and possible application of the CNT1-3. The unique electronic, chemical, and mechanical properties of CNT make it extremely attractive for electrochemical sensi…  相似文献   

19.
1 INTRODUCTION In contrast to the old-line academic and practical studies of 1-phenyl-3-methyl-4-benzoyl-5-pyrazo- lone (PMBP) on the metal coordination chemistry[1], the complexes of β-ketoamines derivated from PMBP received little attention due to its complicated com- plexation. However, in recent years, there has a sudden growth of this area as a result of its timely interest in biological activities[2]. Recently, a series of β-ketoamines[3] containing PMBP have been prepared fro…  相似文献   

20.
Hydrothermal reactions of three aromatic polycarboxylic acids and the transitional metal cations in the presence of phen and 1,4-bib afford three new coordination polymers: [Cd2(bpp)1.5(Hbpp)(phen)2]n(1), [Mn3(Htptc)2(phen)2(H2O)2]n(2), and {[Cu(btc)0.5(1,4- bib)]·2H2O}n(3)(H2bpp = 2,6-bis(4'-carboxyphenyl)-4-phenylpyridine, H4tptc = terphenyl-2,5,2',5'-tetracarboxylic acid, H4btc = biphenyl-2,2',4,4'-tetracarboxylic acid, phen = 1,10-phenanthroline, and 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene). Their structures have been determined by singlecrystal X-ray diffraction analyses, elemental analyses, IR spectra, and powder X-ray diffraction(PXRD) analyses. In compound 1, the CdII cations are linked by bpp2- to form one ladder structure, based on which a 3D network is constructed with the help of non-covalent interactions. The topology of 2 is a 3D(3,4,5)-connected framework with the Point Schl?fli symbol of(42.6)32(4.62.8)(45.64.8)2. Compound 3 shows an unprecedented 3D(4,4)-connected framework with the Point Schl?fli symbol of(64.82)2(65.8). Moreover, the luminescent property of 1 has been investigated.  相似文献   

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