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1.
1INTRODUCTION Recently,cyano-bridged lanthanide-transition me-tal complexes have been extensively investigateddue to their potential applications as precursors in the preparation of rare earth orthoferrites,fluores-cent and magnetic materials[1].Various complexes of this system have been obtained in order to ex-plore the relations between structures and pro-perties by using different ligands,such as DMF,4,4?-bipy,and so on,to fill the coordination sites of lanthanide ions[2~9].But up to…  相似文献   

2.
1INTRODUCTION The construction of metal-organic coordination polymers based on covalent interactions[1]or supra-molecular contacts such as hydrogen-bonding and/orπ-πinteractions)[2]is now of great interest not only due to the enormous variety of intriguing structural topologies themselves,but also to their unexpected physical and chemical properties for potential prac-tical applications as functional materials.Many N-containing ligands,such as4,4?-bipyridine,2,2?-bi-pyridine and1,10-phen…  相似文献   

3.
1INTRODUCTION Recently,the design and preparation of coordina-tion polymers with new porous frameworks are of great interest due to their potential functionalities such as catalysis,gas absorption,separation and molecu-lar recognition.In designing1-D,2-D and3-D porous coordination polymers,the selection of appropriate ligands is crucial for determining the structure.The mixed-linker systems of both carboxylates and pyri-dyls have proved to be effective for the preparation of novel coordi…  相似文献   

4.
<正> INTROdUCTION. This is one of serial compounds with ligands of trinitrate and diphenyl sulfoxide. In order to research rules of coordination of lanthanide complexes, we have determined the structure of the title compound by X-ray analysis.  相似文献   

5.
A new cadmium polymer [Cd(NBA)(μ3-OH)(4,4′-bipy)1/2]n 1 (NBA = m-nitrobenzoic acid and 4,4′-bipy = 4,4-bipyridine) has been synthesized by hydrothermal reaction. Its structure was determined by single-crystal X-ray diffraction method, and characterized by elemental analysis and IR spectrum. The crystal is of monoclinic, space group C2/c, with a = 15.6912(9), b = 25.9394(15), c = 6.7332(4) ′, β = 114.7700(10)°, V = 2488.4(3) 3, C12H9CdN2O5, Mr = 373.61, Z = 8, Dc = 1.995 g/cm3, μ = 1.776 mm-1, F(000) = 1464, R = 0.0411 and wR = 0.1128 for 2130 observed reflections (I > 2σ(I)). X-ray diffraction studies reveal that the compound features a layered structure, in which 4,4′-bipy ligands bridge Z type of double chains [Cd(μ3-OH)]n and NBA ligands locate at the two sides of the layer. The π-π interactions between the benzene rings of NBA ligands of two adjacent layers lead to the 3D framework.  相似文献   

6.
One-dimensional chain copper(Ⅱ) coordination polymer has been synthesized and characterized in the solvent mixture of water and alcohol with o-acetamidobenzoic acid,4,4'-bipyridine and copper perchlorate.It is of tetragonal,space group P41212 with a=1.57756(10),b= 1.57756(10),c=2.1438(3)nm,V=5.3352(8) nm3,Dc=1.524 g/cm3,Z=4,F(000)=2536,R= 0.0479 and wR=0.0979.The crystal structure shows two coordination modes.The copper(1) is coordinated with two nitrogen atoms of one 4,4'-bipyridine molecule and two oxygen atoms from two o-acetamidobenzoic acid molecules,forming a distorted tetrahedral coordination geometry;the copper(2) is coordinated with two nitrogen atoms of one 4,4'-bipyridine molecule,four oxygen atoms from two o-acetamidobenzoic acid molecules and two water molecules,generating a distorted octahedral coordination geometry.The result of TG analysis shows that the title complex is stable below 180.0 ℃.  相似文献   

7.
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   

8.
1 INTRODUCTION In recent years, the design and synthesis of metalorganic coordination polymers have attracted considerable attention, for such supramolecular assemblies have interesting structures as well as potentiaapplications as smart optoelectronic, magnetic andporous materials. By judicious selection of ligandand metal coordination geometries, control over thetopology and geometry of the infinite networks canbe gained. As neutral donor ligands, 4,4?-bpy, pyrazine and imidazole which …  相似文献   

9.
1 INTRODUCTION The rational design and synthesis of new metal- organic frameworks have generated considerable interest in supramolecular chemistry and materials science owing to their intriguing structural diver- sities and potential applications as functional mate- rials[1~6]. Carboxylate-containing ligands have attrac- ted considerable attention because of the various coordination modes of carboxylate group, the ability to form hydrogen bonds and the potential applica- tions as functio…  相似文献   

10.
1 INTRODUCTION Nitronyl nitroxide radicals (NITR), stable organic radicals, have played an important role in the design and synthesis of molecular magnetic materials[1, 2]. However, nitronyl nitroxide radicals are poor elec- tron-donor ligands and their coordination ability is limited. Recently, it has led to the development of functionalized nitronyl nitroxide radicals in which a strong coligand is incorporated. Due to the strong coordinate ability of nitrogen atom from pryidinyl ring,…  相似文献   

11.
1 INTRODUCTION Inorganic-organic coordination framework has captured the interest of chemists due to its potential applications in adsorption, catalyst, separation and host-guest recognition. Generally, it builds upon the coordination of rigid multi-dentate bridge ligands with proper center metallic ions, and furthermore, weak interactions like hydrogen bond are involved[1, 2]. As an excellent N-donating ligand, 2,2?-bipyridine could coordinate with most transition metals to ge- nerate co…  相似文献   

12.
1 INTRODUCTION Much attention has been paid to 1D, 2D and 3D coordination polymers because they can meet the need of functional materials with desired structures and properties[1~5]. One strategy in the design and synthesis of coordination architectures is the buil- ding-block approach. Commonly, bi- or multidentate organic ligands containing N[6, 7] or O[8, 9] atoms have ever been used in the construction. In our cur- rent work, we have selected melamine ligand as the main building bl…  相似文献   

13.
1 INTRODUCTION Recently construction of new coordination poly-mer networks through the rational combination oforganic ligands ‘spacers’and metal ‘nodes’ is an areaof intense interest[1~3] because of their capability ofshowing novel magnetic[4], nonl  相似文献   

14.
A new organic-inorganic hetero-coordination polymer with three different kinds of ligands [Co(4,4'-bpy)(NCS)2(py)2]n is synthesized in the extremely mild condition. The X-ray diffraction reveals that the title polymer has a highly tactic three-dimensional cagelike supramolecular structure. Although the coordination bond makes it a one-dimension chain, the hydrogen bond plays an important role in the formation of 3-D supramolecular frameworks. The determination of magnetic properties has been carried out, and shows that it behaves weak antiferromagnetic property with J(4,4'-bpy) = -3.8 cm-1.  相似文献   

15.
Fourier-transform infrared(FTIR),Raman and ultraviolet-visible spectra of 4,4'-bipyridine and its me-tal-organic coordination compounds synthesized from 4,4'-bipyridine and nitrate of Co(Ⅱ),Ni(Ⅱ) and Zn(Ⅱ) were measured and analyzed,respectively.The main FTIR and Raman bands were assigned in detail.The relationship between these characteristic bands and the structure of ligands and coordination compounds were discussed.  相似文献   

16.
1 INTRODUCTION The pyridyl-phosphine ligands have been widely used for many years to synthesize hetero- or homo-nuclear metal complexes[1], as electronic differentiation associated with the hard (N) and soft (P) donor atoms dictates their unique reactivities and coordination modes. One of the most common pyridylphosphines studied to date is (2-C5H4N)PPh2 which displays numerous ligating modes ranging from P-coordination and P,N-chelation to the more common P,N-bridging of two metal …  相似文献   

17.
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   

18.
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   

19.
1 INTRODUCTION Recently, the chemistry of lead is of interest in relation to its toxicity and effects on intelligence in human populations[1~3]. The design of drugs to coun- teract the effects of lead poisoning requires estab- lishing the preferred ligands of Pb(II) and their ste- reochemistry. Consequently, synthesis of chelated- form antidotes for lead(II) ion toxicosis has attracted more and more attention, and numerous reports con- cerning experimental coordination chemistry of lead(…  相似文献   

20.
The title compound has been synthesized, the crystal structure of which has been detorminedby the single-crystal X-ray diffraction method. The crystal belongs to triclinic space group C-P1 with the unit cell parameters: a =9.535(2)A, b = 9.740(2)A, c = 15.795(4)A, α = 89.85(2)°, β = 91.80(2)°, γ = 99.37(1)°,ν = 1446.6A~3, Ζ = 2. The structure is refined to R = 0.075, R_w = 0.074 for 1903 reflections. There are diverse bonding modes of molybdenum and sulfur in this eompound. The twosulfur atoms at the center bond to three molybdenum atoms from respective sides and formthe two apices of a trigonal bipyramid. Besides, there are S_2~(-2) ligands and a polysulfur chaincomposed of three sulfur atoms. The coordination number for the three molybdenum atomsis seven. Their coordination polyhedra are somewhat distorted pentagonal bipyramid. Eachof the three NO ligands coordinated to molybdenum gives a linear group of Mo-N-O, whilethe fourth NO ligund bonded with a polysulfur chain forms a bent group of S-N  相似文献   

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