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1.
<正> PRELIMINARY INFORMATION. The title compound is a member of a series of cobalt complexes of polydentate ligands currently being investigated. It was prepared by the reaction of CoSO_4·7H_2O with phenanthroline in the equimolar ratio.  相似文献   

2.
Introduction The metal extraction is a process of complex formation by organic ligands with metal ions or corresponding ionic groups, that is to say, it is a multicomponent coordination process in the heterogeneous phase system. The property of extraction is chiefly dependent on the stability of metal complexes, which is closely related to both the structure of ligands and the nature of metal ions. Therefore, the physicochemical behaviour of the substituent in the ligand will influence the extractive ability of the extractant for a certain  相似文献   

3.
刘晓川 《色谱》2006,24(1):73-80
 A review on the principles and applications of boronic acids as affinity ligands for the chromatographic separation of carbohydrates, nucleic acid components, glycoproteins, and other small biomolecules. The mechanisms of interactions between boronate ligands and analytes are described. Various boronate ligands and supports are discussed. Examples of the use of boronate affinity chromatography for separation of each class of analytes are presented.  相似文献   

4.
Two oxygen adducts of different geometric isomers of the tetrakis(μ-2-anilinopyridinato) dirhodium unit, Rh_2(ap)_4~+, have been synthesized and characterized. Rh_2(ap)_4O_2(4,0) is the oxygen adduct 1 of 4, 0 isomer; and Rh_2(ap)_4O_2(2, 2) is the oxygen adduct 2 of 2, 2 isomer. The ESR spectra of both oxygen adducts show that there is a characteristic signal of a superoxide ion, g=2.03. The 4, 0 isomer with different axial ligands gives the order of A_Ⅱ values; O_2~-≈ClO_4~-相似文献   

5.
The stability constants of the binary complexes ofCu~(2+) with isoquinoline and benzimidazole as well as the ternarycomplexes of Cu(ATP)with the same ligands have been measuredin aqueous solution spectrophotometrically and a strongstacking interaction between the heteroaromatic ring of theligands and the purine moiety of ATP has been found.The factof this stacking interaction is much stronger than that in thesystems of Cu(ATP)with pyridine and imidazole shows thatthe stacking interaction increases with the size of theheteroaromatic ring of the ligands.  相似文献   

6.
<正> Four complexes of the types of Cp2Ti (OOCC6H4NHPh-o)2 and Cp2TiCl2(Cp=Cp, MeCp= (CH3C5H4-)) have been investigated under the electron impact condition. The experimental results of Cp2Ti(OOCC6H4NHPh-o)2 complexes suggest that the Ti -L (L =OOCC6H4NHPh-o) bond is weaker than Ti -Cp bond and their molecular ions are characterized by the ready loss of L ligands. On the other hand, the molecular ions of Cp2TiCl2 are characterized by the loss of Cp ligands. The characteristic ions [M-HCl]+ and [M - 2HCl]+ are observed in the spectra of (MeCp)2TiCl2.  相似文献   

7.
1 INTRODUCTION The interest in the development of new poly- pyridine ligands derives from several respects. The formation of a stable complex that can be used as a model for the active sites presents in some metallo- proteins. The uncoordinated donor at…  相似文献   

8.
Uranium and molybdenum are important strategic elements. The production of 99Mo and the hydrometallurgical process of uranium ore face difficult problems of separation of uranium and molybdenum.In this study, the four phenanthroline diamide ligands were synthesized, and extraction and stripping experiments were performed under different conditions to evaluate the potential application of these ligands for separation of U(Ⅵ) over Mo(Ⅵ). With the growth of alkyl chain, the solubility of...  相似文献   

9.
1 INTRODUCTION In the past decade, there was a large increase of research activity on the control of polymer micro- structures by varying the structures of ligands in single-site olefin polymerization catalysts. The ma- jority of such investigations reported till now have been focused on metallocenes[1] of early transition metals or compounds of late transition metal[2, 3] dii- mide catalysts[4~7]. The polymerization mechanisms[8~10] and the influence of ligands on the regioselectivity …  相似文献   

10.
n-Salicylideneamino acids and their Cu(Ⅱ) complexes are synthesized. The structures of the compounds are characterized by elementary analysis, molar conductance, magnetic susceptibility, electronic and infrared spectra. The stability constants and the antibacterial activities have been determined. The relativity between antibacterial activities and structures of ligands and stability of complexes has been preliminarily studied.  相似文献   

11.
<正> PRELIMINARY INFORMATION. The title compound, is one of the products synthesized by a reaction of bis(triphenylphosphine)-platinum, carbon monoxide and chlorine gas in sodium hydrate solution at room temperature. An X-ray structural analysis has been undertaken to clarify unambiguously the arrangement of ligands around the triangle platinum cluster core. This has been  相似文献   

12.
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   

13.
The tide compound is formed by controlled hydrolytic polymerization in nonaqueous solution of simple oxo-bridged binuclear ferric salts under the presence of carboxylate ligands. The rhombohedral crystalline form of the cluster with six imidazole molecules, which has crystallographically required C3v symmetry, will be reported. The largest Fe-Fe distance in the undecairon oxo-hydroxo cluster is about 0.68 nm and the cluster has a diameter near 2 nm, which implies that this cluster reaches a nanometer-sized dimension.  相似文献   

14.
The synthesis of acetic acid by carbonylation of methanol in the presence of Ni(Ⅱ)complexcatalysts at 200℃ under mild pressure was studied.The results showed that among the tested catalyststhe MCC-Ⅰ catalyst had the best performance for the reaction with a mathanol conversion of 98.2%and a carbonyl compound yield of 94.5%.The effects of the pKa values of ligands and the Debyevalues of solvents on the reaction were determined and a suggested mechanism involved in this reactionwas briefly discussed.  相似文献   

15.
 Chiral S,P-donor ferrocene-derived ligands were synthesized and applied in the asymmetric hydrogenation of quinolines using the [Ir(COD)Cl]2/S,P-ligand complex as the catalyst in the presence of iodine. The effects of the solvent and hydrogen pressure on conversion and enantioselectivity were examined, and up to 82% ee was obtained. The planar chirality plays an important role in this reaction. R- and S-enantiomers of 1,2,3,4-tetrahydroquinoline derivatives were obtained using ligands 3 and 5, respectively.  相似文献   

16.
袁福根  王海燕  张勇 《中国化学》2005,23(4):409-412
Reaction of anhydrous YbC13 with 2 equiv, of sodium 2,4,6-tri-tert-butylphenoxide (ArONa, Ar=C6H2-t-Bu3-2,4,6) and 2 equiv, of potassium diphenyl amide in THF afforded the first bis(aryloxo) amido-lanthanide complex of (ArO)2Yb(NPh2)2K(THF)4 (1). In 1, the ytterbium and potassium were bridged via diphenyl amido ligands.The ytterbium metal center was coordinated to two oxygen atoms of aryloxide ligands and two nitrogen atoms of diphenyl amido ligands in a conventional distorted tetrahedral fashion, while the potassium interacted in η^2-fashion with two phenyl rings of the diphenyl amido ligands besides four THF molecules. 1 displayed moderate catalytic activities for the polymerization of methyl methacrylate and acrylonitrile.  相似文献   

17.
A novel ternary complex of Cu(pcpa)2(aben)2 (pcpa=p-chlorophenoxyacetic acid anion,aben=2-amino benzothiazole) was synthesized by the reaction of copper acetate,2-amino benzothiazole and p-chlorophenoxyacetic acid.Elemental analysis,IR,UV and X-ray single-crystal diffraction were carried out to determine the composition and crystal structure.The crystal crystalli-zes in the monoclinic system,space group C2/c with a=25.795(4),b=7.384(3),c =17.741(6),β=107.47(2)°,C30H24Cl2CuN4O6S2,Mr=735.09,V=3223.2(18) 3,Z=4,Dc=1.515 Mg/m3,λ(MoKα)=0.71073 ,μ=1.022 mm-1,F(000)=1500,the final R=0.0464 and wR=0.1244.A total of 3218 unique reflections were collected,of which 2228 with I 2σ(I) were observed.The Cu(II) atom is four-coordinated with two carboxylate oxygen atoms of the two pcpa ligands and two nitrogen atoms in thiazole rings of two aben ligands.The analysis of crystal structure shows intermolecular and intramolecular hydrogen bonds between amino-nitrogen atoms of the two aben ligands and carboxylate oxygen atoms of the two pcpa ligands.The antimicrobial properties of the title complex and its two free ligands were tested against representative bacterial and fungal strains.Results show that the antibacterial activity of the complex is less than or equal to that of 2-amino benzothiazole,but for yeasts and moulds,it exhibits excellent inhibitory effect better than that of its two free ligands.  相似文献   

18.
Two multidentate ligands 2,9-di[6'-(2″-hydroxyl-3″-methoxyphenyl)-n-2',5'-diazahexyl]-1,10-phenanthroline(LA)and 2,9-di(6'-α-phenol-n-2',5'-diazahexyl)-1,10-phenanthroline(LB)were synthesized and fully characterized.Protonation of the ligands and the stability of the complexes of the ligands with divalent metal ions were investigated.The trinuclear metal complexes [Cu(Ⅱ)and Zn(Ⅱ)] of the ligands were studied,as catalysts,for the transphosphorylation of the RNA-model substrate 2-hydroxypropyl-p-nitrophenyl phosphate(HPNP).The second-order rate constants of HPNP-hydrolysis catalyzed by M3L and M3LH-1 were obtained,which indicated that Zn3LBH-1 was the most efficient catalyst among them.The proposed mechanisms included the activation of the substrate via binding to the metal ions and intramolecular nucleophilic attack by the deprotonated C2-hydroxyl of HPNP.  相似文献   

19.
1 INTRODUCTION Procedures to synthesize copper(I) complexes are of great interest because of the diversity of products resulting from almost the same methodology. It has long been known that four-electron-donor diphosphine compounds Ph2P(CH2)nPPh2 are excellent bidentate ligands[1]. The chelating tendency decreases as the chain length increases, so that for the ligands Ph2P(CH2)nPPh2, the tendency to chelation is the greatest for bis(diphenylphosphino)ethane. Copper(I) displays wide…  相似文献   

20.
The electrocarboxylation of benzyl chloride with CO_2 catalyzed by metalloporphyrins and the effects of different kinds of central metals and ligands on catalytic activities are reported. These metalloporphyrins whose central metals can form corresponding M (Ⅰ) complexes such as CoTPP, FeTPP have high activities. With water-soluble porphyrin ligands such as TPPS, TTMAPI, the corresponding metalloporphyrins have high catalytic activity. Electron-with-drawing groups on the porphyrin ring cause the lowering of activity.  相似文献   

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