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1.
1 INTRODUCTION The ability of dialkyldithiocarbamate anion, -S2- CNR2 (dtc) ligand, to bind metal has been known for many years[1, 2]. It forms a chelate with virtually all transition elements and is proven to be a versatile chelating agent for the separation and extract of metals in analytical chemistry and mineral floa- ting[3~5]. Water soluble dialkyldithiocarbamate com- plexes have been tested in various medical appli- cations[6]. Some of substituted dithiocarbamate salts also show …  相似文献   

2.
1 INTRODUCTION Nickel is vital for organism as a trace element and it often acts as component or secondary factor of enzyme. In the latest two decades, biological inor- ganic chemistry of nickel has become one of the hottest fields and the coordination chemistry of nic- kel has made a great progress[1]. Complexes built upon organic aromatic carboxylic acid and metallic ion have attracted chemists’ interest for years due to their potential applications in material, medicine, molecular ele…  相似文献   

3.
1 INTRODUCTION Hydrothermal synthesis of Mo(V) phosphates has allowed various structures, all characterized by the presence of identical clusters with the composition Mo12MP8X62 (X = O, OH) to be stabilized[1~6]. Many Mo(V) phosphates with such clusters have been iso- lated to date. The first compound was discovered by Haushalter and Lai[1] for M = Na with the formula (PPh4)2[(H3O)2NaMo6P4O24(OH)7]?5H2O. Recently, a second type of structure has been observed for M = Na (Na8(…  相似文献   

4.
1 INTRODUCTION The assembly of coordination networks is a field of increasing interest[1~4]. Research along this line is induced by the idea that coordination networks have potential technological applications such as optoele- ctronic devices and microporous materials for shape and size separation and catalysis[5~7]. In this paper, there has been current interest in using polycarboxy- late as anion linking groups to support stable poly- meric coordination open frameworks with transition m…  相似文献   

5.
1 INTRODUCTIONThe inorganic chemistry concentrating on polyoxometallates, is in a position to connect elementary building blocks and their derivatives in different ways, enabling people to synthesize a large variety of remarkable substances, especially those in the "nanoworld". Of particular importance is the anionic-type which has {MOx}-type building-block units, where M stands for the d block elements in high oxidation states.[1] In 1973 Weakley, Evans and Showell isolated[2] K10P2W1…  相似文献   

6.
1 NTRODUCTION Pagodane ([1.1.1.1]-pagodane) is the trivial name assigned to the D2h-symmetry undecacyclic poly- quinane undecacyclo-[9.9.0.01,5.02,12.02,18.03,7.06,10. 08,12.011,15.013,17.316,20]-eicosane (Fig. 1). It has been synthesized[1] and subsequently studied by Prinzbach and co-workers for more than twenty years[2, 3]. Des- cribed as a waxy solid melting without decomposi-tion and stable to at least 600 ℃ in gas phase, pa- godane is interesting for its exotic structure and as an…  相似文献   

7.
IntroductionRecently,a considerable interest has been fo-cused on the complexes of zinc with amino acidsdue to their excellent additives in medicine foodstuff and cosmetics[1— 6] .The investigation on thethermal behavior and the thermochemistry of somezinc amino acids is important to its further applica-tion,which has been reported in references[4,5 ,7— 1 0 ].However,the studies on solid complexZn( Thr) SO4· H2 O has not been reported,whichcan provide the necessary data and the foundation…  相似文献   

8.
<正> INTRODUCTION. The derivatives of ferrocene are found to be increasingly used in the area of the catalysis of combustion reactions of high energy fuels and new material research. Therefore, more attention has been paid to these compounds. This work is a part of our systematic investigation on a  相似文献   

9.
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   

10.
1 INTRODUCTION Pyrrole and its derivatives have attracted much attention due to their chemical properties as well as biological activities[1]. They have been widely used to produce pharmaceutical, essences, biochemicals, etc. It has been found that a great number of pyrrole derivatives present antitumor and antiviral activi- ties[2 ~ 5]. During our searches for bioactive com- pounds, a series of pyrrole derivatives were synthe- sized[6, 7]. We report here the synthesis of 3-(pyrrole- 2?-…  相似文献   

11.
IntroductionPolyoxometalates constitute an enormous classof compounds whose unusual versatility and reac-tivity afford practical applications to many fields,such as catalysis,biology,medicine,and materialsciences[1— 4] .In recent years,hydrothermal tech-nique has become a vital tool in self- assemblychemistry.This technique,in combination with or-ganic templates,has been demonstrated to be wellsuited for the synthesis and the crystal growth ofpolyoxometalates with novel structures[5— 9] .Amo…  相似文献   

12.
0 IntroductionThe complexes formed by rare earth and aromatic carboxylic acid have many special structuresand interesting luminous properties, thus arouse people's interest to study them. They can be used.in many areas such as extraction and separation, germicide, catalyst, luminous materials andfunctional materials and so on.The crystal structure and luminescence spectra of the europium p-chlorobenzoate complex withl, 10-phenanthroline has been reported"], but the study for its non-isothermal…  相似文献   

13.
Introduction Molecules containing different kinds of metal ions play an important role in molecular magnetism.1-3 So considerable attention has been paid to synthesizing heteronuclear complexes.1-4 As a potential bridging ligand, thiocyanate can coordinate to a harder metal center and softer ones with N and S atoms respectively. The complexes of thiocyanate and representative hard acidFe(III) ions usually have a six-coordinate octahe-dral structure such as [Fe(SCN)n]3-n and (Bu4N)4[Ag2-F…  相似文献   

14.
The structure of Na_2H_2[H_2V_2W_(18)O_(62)]12H_2O has been determined by x-rayanalysis.The crystals are trigonal,space group R3m,with cell parametersa=37.613(11),c=12.972(7)A,V=15901(13)A~3,and Z=9.The structure model wasrefined by full-matrix least square to R=0.065 for 1702 reflections with F>4σ(F).The existence of the[H_2V_2W_(18)O_(62)]~(4-)heteropolyanion in the crystals has beenconfirmed.It is composed of two VO_4 tetrahedra and eighteen WO_6 octahedralinked to gve the Dawson-type structure.  相似文献   

15.
<正> Introduction. The complexes of Mo(V) and oxalate are found to exist in several various configurations. As an anologous compound for the activecenter of Mo enzymes they have attracted broad attention. It was found by Sobczak and Ziolkowski in 1976 that these types of complexes had a higher catalytic selectivity in the epoxidation of olefine by hydroperoxides  相似文献   

16.
1 INTRODUCTIONAlthough vanadium plays an increasingly recognized role as a biometal[1~4], little is known about the structure and function of vanadium compounds in living organisms. A classical and nevertheless rapidly developing field of application for oxovanadates and related compounds is their use as catalysts in polymerization and oxidation reactions[5,6], and recent interest has focused on oxovanadates as model compounds for the interaction of oxovanadates with the active sites of en…  相似文献   

17.
2,2'-Bis (4H-3, 1-benzoxazin-4-one) (BBON) has been proved to be an effective chainextender for poly (ethylene terephthalate) (PET). In order to study the reaction mechanismand kinetics of chain-extending reaction, β-bishydroxyethylene terephthalate (BHET) wasselected as model compound. The NMR data, IR spectra and number average molecularweight (M_n) of the products obtained from the reaction of BBON and BHET verify thatBBON is a hydroxyl-reactive extender. The mechanism was discussed. Kinetics dataindicate that extending reaction is a second order reaction, and BBON has high reactivity.The activation energy (E_a) was measured.  相似文献   

18.
Crystal and molecular structure of [C6H2(COO)4Zn2(H2O)5]·2H2O has been determined by X-ray diffraction technique, Mr = 507. 0,monoclinic,space group P21/n,a = 5. 925(1), 6 = 23. 613(9) ,c= 11. 790(5) A ,β= 96. 36 (3)°, V=1639. 3 (1. 0) A3,Z=4,DC = 2. 05g/cm3,λ=0. 71069 A,μ(MoKa) = 30. 9/cm-1,F(000) = 1024e. The structure was solved by Patterson and Fourier techniques and refined by least-squares method to a final conventional R value of 0. 055(Re = 0. 059)for 1557(I>3σ(I))reflections. Both atoms Zn(1) and Zn(2) are bridged by the Z,E-type of the car-boxyl group, in addition, Zn (1) is monodentate-bonded to the three remaining carboxyl and Zn(2) is bonded to five water molecules. The crystal structure shows a 2-dimensional polymeric network along(010)face. The Zn(l) -O distances are in the range of 1. 94~ 2. 01 A (average 1. 98 A ). The Zn(2) -O distances are in the range of 2. 06~2. 21 A (average 2. 12A).  相似文献   

19.
1 INTRODUCTION The chemistry of divalent lanthanocenes has de- veloped rapidly. Attempts to extend the chemistry beyond the traditional realm of the lanthanocenes have led to the syntheses and structural characteri- zations of a number of lanthanide (II) complexes bearing various ligand systems. Aryloxide ligands have been attractive for their strong bonds with lan- thanide atoms and readily steric modification by the choice of substituents. A series of divalent lantha- nide aryloxides …  相似文献   

20.
0IntroductionAs the active sites of several mononuclear en-zymes are five-or six-coordinate manganese speciescontaining coordinated carboxylate groups,water andnitrogen-donor molecules research on the coordinationcompounds of manganese with such coligands hasgrown[1,2].There has been extensive interest in man-ganese chemistry due to the involvement of manganesein many biosystems and magnetic materials[3 ̄5].Theisophthalate as a potential bidentate ligand seemsquite suitable for self-assembly s…  相似文献   

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