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1.
冯云龙 《结构化学》2002,21(1):22-25
1 INTRODUCTION A number of isonitroso-b-diketones and isonitroso-b-ketoesters such as isonitrosoacetyl- acetone(Hiaa), isonitrosobenzoylacetone(Hiba) and isonitrosoethylacetoacetate (Hieaa) have been employed as reagents in spectrophotometric determination of iron, palladium and ruthenium[1]. Transition metal complexes of such ligands[2] are potential models for metal binding sites in ferroverdin[3]. They were found as dyes and light-absorbing agents for the acceleration of the sol…  相似文献   

2.
Synthesis and Structural Characterization of [Mn(sapn)(H2O)2]Br   总被引:1,自引:0,他引:1  
1 INTRODUCTION Many of the recent advances in the coordination chemistry of manganese have been driven by the involvement of the manganese in several biological redox-active systems[1,2], of which the most important is the oxygen-evolving complex (EOC) of photosystem II (PS II) in green plants [3]. Since the preparations and structural characterizations of the complexes containing N,O-donor ligands have been studied extensively as simple active-site models for the photosystem II[4,5]…  相似文献   

3.
冯云龙 《结构化学》2003,22(2):133-136
1 INTRODUCTION The interest in the complexes of transition metals with ligands ketoxime[1, 2] as potential models for metal binding sites in ferroverdin[3, 4] has prompted the investigation on the structures and the overall coordination geometry of the metal centers in these complexes. Oxime derivatives are interesting ligands since the ketoximes are found to chelate transition metals through the N (oxime) and O (ketone) atoms[5, 6]. However, monodentate coordination via only one O or …  相似文献   

4.
1INTRODUCTION Manganese complexes have drawn considerable interests in recent years because they can serve as models for active sites of manganese-containing me-talloenzymes,such as photosystem II(PSII),man-ganese superoxide dismutase(MnSOD),manganese ribonucleotide reductase(MnRR)et al[1].The binu-clear manganese enzymes,including catalase,MnRR and arginase,were indicated to have carboxylato-,oxo-,hydroxo-or aquo-bridged cores[2~4].Structures with Mn substituted into the iron ribon…  相似文献   

5.
冯云龙 《结构化学》2003,22(5):544-546
1 INTRODUCTION The chemistry of nickel complex with multi- dentate Schiff base ligands has attracted particular attention because this metal can exhibit several oxi- dation states[1]. Such complexes with different oxi- dation states play an important role in bioinorganic chemistry and redox enzyme systems[2], and many of them can provide the basis of models for active sites of biological systems or act as catalysts[3]. Nickel complexes with tetradentate N2O2 and tri- dentate N2O Schi…  相似文献   

6.
陈巍  杜淼  张若桦  卜显和 《结构化学》2002,21(3):277-279
1 INTRODUCTION A number of Pt complexes with monosulfoxide have been isolated and characterized[1]. It was indicated that the sulfoxide group trends to coordinate to soft metals (Pt, Pd, etc.) by its sulfur atom[2]. Pt(Ⅱ) trends to bond to disulfoxides in cis-mode and such complexes have potential antitumor activity[2]. However, only few examples of such complexes have been structurally characterized[3]. We will report herein the crystal structure of a new Pt(Ⅱ) complex with a disulf…  相似文献   

7.
1 INTRODUCTION During the last decade the manganese che- mistry has aroused great interest due to its diverse redox functions of enzymes in photosystem Ⅱ and its specially structural, magnetic and spectroscopic properties[1, 2]. A lot of manganese complexes involving carboxylate ligands have been reported, and their properties been fully explored[3, 4]. The coordination environment of the manganese site in biosystem often consists of oxygen and nitrogen atoms from the carboxylate groups…  相似文献   

8.
1 INTRODUCTION There has been great and considerable interest in the study of copper nitrite complexes because they are relevant to the study of copper-containing enzymes involved in the denitrification process[1]; in particular, copper-nitrite complexes are potentially relevant to the nitrite reductases[2] (the enzyme from Achromobacter Cycloclastes) which convert NO2- to NO and/or N2O. Many attempts have been made to synthesize a variety of copper-nitrite complexes, in which the n…  相似文献   

9.
1 INTRODUCTION The design and synthesis of polynuclear com- plexes have attracted chemists?attention in the contemporary chemistry, since their clusters maybe lead to novel materials with magnetic, optical, electronic and catalytic properties of the constituent metals[1~3]. It is also prevalently interesting to synthesize high-nuclearity metal complexes for their nanoscopic dimensions[3, 4]. Spectroscopic properties of the lanthanides are widely used in the study of biological systems. …  相似文献   

10.
1 INTRODUCTION The interest in vanadium chemistry from a biolo-gical and pharmacological perspective has explodedover the past 20 years. This is mainly based on thediscoveries of the insulin-like effect of vanadium compounds[1, 2], and the presence of vanadium in certainhaloperoxidases and nitrogenases[3, 4]. Vanadium complexes with organic ligands mightbe candidates for therapy of diabetes, consequentlydesign and synthesis of new complexes are of greatinterest recently[5, 6]. On consid…  相似文献   

11.
1 INTRODUCTION Recently polynuclear iron (Ⅲ) clusters have attracted considerable attention in bioinorganic chemistry due to their presence in the protein ferritin and the related materical hemosiderin[1, 2]. The binuclear oxo-bridge non-haem iron com- plexes (containing the FeⅢOFeⅢ unit) which provide models for the diiron site in the protein involved in the storage (haemrythrin) and on the reductive activation (methanemonoxygenas, ribonclectidereductas) of dioxygen[3,4]. Also, wel…  相似文献   

12.
1 INTRODUCTION Transition metal Schiff base complexes have been extensively studied in the past two decades for their various crystallographic features, enzymatic reactions, steric effects[1~4], catalysis and magnetic properties[5, 6] as well as their important role in organisms[7, 8]. Most of these first-row materials are biologically essential with a number of their complexes showing bioactivities[9, 10]. Herein we describe the synthesis and X-ray structure of the cadmium (Ⅱ) compl…  相似文献   

13.
冯云龙  刘世雄 《结构化学》2003,22(3):275-278
1 INTRODUCTION Transition metal complexes of N-R-isonitroso- b-ketoimine have received considerable interest, because the isonitroso (oximo) group can coordinate to metal atoms through its oxygen and/or nitrogen atoms to form several geometrical isomers[1~4]. Some palladium(Ⅱ) complexes with N-R-isonitro- soacetylacetoneimine (abbreviated to R-Hiai)[4] and N-R-isonitrosoethylacetoacetate (abbreviated to R- Hieai)[5] have been reported. Here we will report the structure of a palladi…  相似文献   

14.
1 INTRODUCTION The complexes containing dithiolate ligands have played a well-established role in modern coordination chemistry[1]. There is continuous interest in complexes of chalcogenolate ligands with transition metals such as complexes of Pd[1], Mo[1], Au[2], Ir[3~6], Rh[4, 5], Co[7] and Re[1, 8] containing a chelating 1,2-dicarba-closo-dodecabarane-1,2-dich- alcogenolate ligand. Some of these complexes have become important in the study of new molecular materials[1, 9, 10]. Th…  相似文献   

15.
1 INTRODUCTION Recently coinage metal complexes of poly- dentate phosphines are of great interest owing to the applications in diverse areas such as supramolecular design, photophysics and catalysis[1~4]. It is well- known that the binuclear coinage metal complexes of diphosphine [M2(diphosphine)2(MeCN)2]2+ (M = Cu, Ag, Au)[5~16] are excellent precursors for the design of polynuclear or polymeric materials with desired properties due to the easy substitution of weakly coordinated ac…  相似文献   

16.
1 INTRODUCTION The lanthanide amide complexes are excellent synthetic precursors for lanthanide derivatives, par- ticularly in the reactions involving protonic rea- gents[1]. A few types of lanthanide amide complexes, from homoleptic three- to four-coordinate, have been known for some time[2~4]. Recently, we begin to examine the utility of amide with less steric bulk, such as diphenylamide and diisopropyamide, as li- gands to synthesize homoleptic lanthanide amide complexes. For diphen…  相似文献   

17.
1 INTRODUCTION Synthesis of transition metal complexes with Schiff-base has been a subject of considerable importance [1,2]. They are not only good complexing agents for Schiff-base, but also good bactericide and antitumour agent [3,4]. At present, there is a spectacular growth in this field. Recently, some bridged binuclear complexes have received much attention on account of their biological relevance and condensed-phase magnetic properties[5,6]. Especially, the complexes containin…  相似文献   

18.
1 INTRODUCTION The syntheses and structures of carboxyl complex- es have captured the interest of chemists for years due to their potential applications in many fields, such as materials, medicine, molecular electro-che- mistry and biochemistry[1~3]. So far, to the best of our knowledge, cadmium complexes with aromatic carboxylic acid as ligands have been intensively studied[4~7], but those with heterocyclic carboxylic acid as ligands are much less. α-Furoic acid is widely used in orga…  相似文献   

19.
Cis-dioxo-metal complex ( NH3CH2CH2NH2 ) 2.5 [ Mo0.5^(V)W0.5^(VI)O2 ( OC6H4O ) 2] 1 was obtained by the reaction of tetra-butyl ammonium hexamolybdotungstate with 1, 2-dihydroxybenzene in the mixed solvent of CH3OH, CH3CN and ethylenediamine,and characterized by X-ray diffraction, UV-vis and EPR analysis. Compared with its analogous complexes (NH3CH2CH2NH2)3[Mo^(V)O2(OC6H40)2] 2 and (NH3CH2CH2NH2)2[W^(VI)O2(OC6H4O)2] 3, the results show that tungsten(VI) is less active in redox than molybdenum (VI) and that the change of the valence induced by substitution of W(VI) for Mo(V) in EMO2(OC6H40)2]n- does not influence the coordination geometry of the complex anion in which the metal center exhibits distorted octahedral coordination with cis-dioxo catechol. The responses to EPR of complexes 1 and 2 are active but complex 3 is silent,and the UV-vis spectra exhibited by the three complexes are obvious different because of the different electronic configuration between the central Mo(V) and W(VI) ions in the complexes.It is noteworthy that complexes 1 and 2 have the similar EPR signal to flavoenzyme, suggesting that the three complexes have the same coordination geometry feature with the co-factor of flavoenzyme.  相似文献   

20.
1 INTRODUCTION The synthesis of Mo(W)/Cu(Ag,Tl)/S polymeric complexes from the reactions of [MS4]2- (M = Mo, W) with Cu , Ag or Tl remains attractive due to their rich coordination chemistry[1~10] and NLO ma- terials[7, 10]. For example, the reacti…  相似文献   

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