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1.
Reactions of pyridine-2,6-dicarboxylic acid(H2PDA) with cobalt(Ⅱ) acetate resul-ted in two cobalt(Ⅱ) complexes,[Co(HPDA)2].2H2O.0.5CH3OH(1) and [Co2(PDA)2(H2O)5].2H2O(2),which were characterized by single-crystal X-ray diffraction,IR and electronic absorption spectra.For both complexes,every cobalt atom lies in peudo-octahedral coordination geometry,and the whole structures present 3D frameworks linked by π-π stacking interactions and extensive hydrogen bonds.Magnetic studies showed λ =-83.38 cm-1 for(1) and g = 2.50 and J =-1.38 cm-1 for(2).  相似文献   

2.
1 INTRODUCTIONCopper( ) displayswide diversity in itsstructuralchemistry,the copper coor dination number ranging from two to four.Procedures to synthesize copper( )complexes itself are of great interest because of the diversity of products resultingfrom almost the same methodology.Ithas long been accepted that because copper( ) complexesare diamagnetic,and hence,provideno opticalabsorption bands( nod d transition is encountered) for a copper( ) ion with a d10 configuration and noelect…  相似文献   

3.
<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   

4.
1  INTRODUCTIONCopper( ) displays a wide diversity in its structural chemistry,the copper co-ordination number ranging from two to four.Procedures to synthesize copper( )complexes are of greatinterestbecause of the diversity of products resulting from al-mostthe same methodology.Ithaslong been accepted thatcopper( ) complexesarediamagnetic and provide no optical absorption bands( no d- d transition isencountered) for a copper( ) ion with a d10 configuration and no electron spin reso-n…  相似文献   

5.
1 INTRODUCTION Crystal engineering and the design of solid-state architectures have recently become areas of increasing interest[1, 2]. Such crystal engineering may afford new materials with useful properties such as catalytic activity, micro-porosity, nonlinear optical activity, cooperative magnetic behavior and so on. Polynitrile-ligand is one of the ideal multi-functional ligands for crystal engineering and many complexes with polynitriles as ligands have been found to show the spe…  相似文献   

6.
ET is one of the most famous electron-donor molecules, which forms charge-transfer complexes (abbr. CT-complexes) with various types of counterions. These complexes have received intense attention because a wide range of physical properties such as conductivity and superconductivity1, ferromagnetism2-4 and nonlinear optical properties5 was found in these materials. Although the majority of the ET-based CT-complexes were prepared by combining with inorganic counterions, CT-complexes with o…  相似文献   

7.
Iridium(Ⅲ) complexes are one of the most important electrophosphorescent dyes with tunable emissions in the range of visible and near infrared lights,high photoluminescence yields and short lifetimes for high-efficiency organic light-emitting diodes(OLED) with 100% exciton harvesting.This review summarizes the recent development of electroluminescent Ir~(3+) complexes functionalized with host-featured carrier-transporting groups,with emphasis on correlations between functionalization,optoelectronic properties and device performance.According to the introducing approaches,the complexes were sorted with conjugated and aliphatic linkages,as well as the types of functional groups.The modification effect on physical properties and the state-of-the-art device performances were discussed.  相似文献   

8.
Mononuclear Cu(II)bipyridine(1)and phenantroline complexes(2)were synthesized and immobilized by different procedures on H3PW12O40 polyoxometalate(POM).Characterization by XRD and SEM-EDX were performed to assess the preservation of the Keggin structure and stoichiometry of the complex.The immobilized complexes were tested as heterogeneous catalysts for the partial oxidation of tetralin(1,2,3,4-tetrahydronaphthalene)using hydrogen peroxide as oxidant in acetonitrile/water as solvent.[Cu(2,2’-bpy)Cl][H2PW12O40] and[Cu(1,10-phen)Cl][H2PW12O40]oxidized tetralin at room temperature,with 16%conversion with(2),to 1-tetralone and 2-tetralone with 83%selectivity.However,the selectivity for 1-tetralone was only 56%.Different preparation methods for the heterogenization of these complexes on the POM Keggin unit were compared and used to enhance the selectivity to 1-tetralone to 75%.  相似文献   

9.
<正> Introduction. Tertiary diphosphine-cyclopentadienyl-nickel(Ⅱ) complexes were first synthesized by Sato (Sato, et al., 1971), and their boronhydrides were prepared by Zhang (Zhang, et al., 1983). Here we report the crystal structure of the title compound in Order to correlate the reactivity of this type of compounds with their structures and bondings.  相似文献   

10.
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   

11.
Introduction The chemistry of organotin(IV) dithiocarbamate complexes was extensively studied due to their biological activities.1-5 To date, a large number of transition-metal complexes with dithiocarbamate have been synthesized and structurally characterized,6-9 including Ni(S2CNC4H8O)2, Cu(S2CNC4H8)2, Zn(S2CNC4H8O)2 and Fe(S2CNC4H8O)2(DMF). However, the chemistry of main-group metal complexes with dithiocarbamate has been scarcely studied, and few reports have appeared on the s…  相似文献   

12.
1 INTRODUCTION Recently, the low-spin square-planar nickel(II) complexes and high-spin octahedral nickel(II) complexes with Schiff base ligands have received much attention in optical materials[1~3]. Some nic- kel(II) complexes are widely used as lubricating oil, rubber industry additives, a fire-resistant additive and fungicide for leather[4~7]. Also, their adducts with nitrogen have attracted broad attention due to their potential applications as organic conductors and magnetic mate…  相似文献   

13.
A series of novel heteronuclear Ln(Ⅲ)-Cu(Ⅱ) complexes with noncyclic polyether-amino acid Schiff base were synthesized. The general formula is [LnCu_2(H_2TALY)(NO_3)_5](NO_3)_2' nH_2O(Ln=La, Nd, Sm, Gd, n= 4; Ln=Yb, Y, n=3), where H_2TALY = tetraglycol aldehyde bis-lysine Schiff base. It is the first time to report the synthetic method for this new Cu(Ⅱ) complexes and Ln(Ⅲ)-Cu(Ⅱ) heteronuclear complexes. The complexes were characterized by elemental analysis, IR spectra, TG-DTA, magnetic susceptibility, and especially by a 500 MHz NMR spectrometer for 2D-COSY NMR. Coordination mechanism and structures of complexes have been suggested as well. Of particular interest is the potential that the novel complexes obtained may be used as a catalyst, which prompted us to investigate them. It shows 100% conversion with the viscosity-average molecular weight 120 000 for the polymerization of methyl methacrylate (MMA) without addition of any cocatalyst. Furthermore, the complexes with such aliphatic Schiff bas  相似文献   

14.
1 INTRODUCTION There has been considerable interest of copper(II) -hydroxylate complexes in the structural chemistry and biochemistry. There are two structural types in copper(II) -hydroxylate com- plexes: mononuclear[1~6] and dinuclear structure[7~9]. The present work is a part of our study on the copper complexes of -hydroxylated acid and reports the synthesis and structure of a mononuclear copper(II) complex with 9-hydroxy- fluorene-9-carboxylato acid, [Cu(C14H8O3)(C5H13- NO)(H…  相似文献   

15.
TTHA complexes with diamagnetic rare earth ions (La3+, Y3+ and Lu3+) were studied by 1H and 13C NMR spectroscopy. A symmetric structural model was suggested for La(TTHA) complex and an asymmetric model for Y(TTHA) and Lu(TTHA) complexes. The complex formation was dependent on the pH value of the solution. The interactions of La(TTHA) with the additional metal ions (La3+, Y3+ and Ca2+) were relatively weak, but relatively strong for that of Lu(TTHA) with the additional Lu3+.  相似文献   

16.
LIU  Sheng-Nan CAO  Duan-Lin REN  Fu-De REN  Jun 《结构化学》2010,29(10):1459-1466
The structures and energies of the side-on complexes B2(N2)2 and monocyclic Bn(N2)nm (n = 3~6,m = -1~+2) between N2 (1∑+g) and B (2P) have been investigated by the DFT-B3LYP and MP2 methods at the 6-311+G(2d) and aug-cc-pVTZ levels. The analyses of NICS (Nucleus Independent Chemical Shifts),NBO (nature bond orbital),AIM (atoms in molecules) and frontal orbitals have been used to reveal the origin of coordination bond between the π-electron donor N2 group and B atom,accompanied by the comparison with the end-on complexes. The results have indicated that the side-on coordination complexes can be formed due to the relative strong fluidity of the π-electrons,and the nature of the coordination bond has been exposed to be that the N2 group offers 1πu electron to the 2p orbital of boron. The coordinate energies of the side-on complexes are less than those of the end-on complexes. Furthermore,the aromaticity of side-on coordination complex is weaker than that of the corresponding end-on coordination complex.  相似文献   

17.
Five neutral macromolecular polyester gadolinium (Ⅲ) complexes with pendant hydrophobic alkyland aromatic functional groups were prepared. The longitudinal relaxation rates of these complexes weremeasured. One of these Gd (Ⅲ) complexes was chosen for the acute toxicity test and T_1-weighted imagingmeasurement. Preliminary results showed that. compared with Gd-DTPA. the neutral macromoleculargadolinium (Ⅲ) complexes provide higher T_1 relaxivity enhancement and longer function duration.  相似文献   

18.
A series of binuclear eleven-coordinated rare earth complexes with long chain quarternary ammonium salt have been synthesized. The general formula of the complexes may be represented by((CH_3)_3 C_(16)H_(33)N)_4Ln_2(NO_3)_(10) where Ln is La, Ce, Pr, Nd, Sm, Eu, Ga, Ho, Er or Y. The TG curve, the magnetic moment and the dissociation degree of the Nd complexes in alcoholic solution have been determined.((CH_3)_3C_(16)H_(33)N)_4 Nd,_2NO_3)_(10) was chosen as a representative of the complexes for the crystal structure determination. The crystal is monoclinic with space group P. Each Nd atom is coordinated by four terminal nitrate groups bidentately, and two Nd atoms are connected through two O atoms of the nitrate groups forming binuclear complex. Therefore, each Nd atom is surrounded by eleven oxygen atoms. The average bond length of the eleven Nd-O bond is 2.57, while the Nd-O bond length on the oxygen-bridge is 2.62.  相似文献   

19.
1 INTRODUCTION In recent years there has been considerable and increasing interest in the synthesis of transition metal complexes with multidentate Schiff base ligands[1~4] because such ligands can accommodate one, two or more metal centers and may synthesize homo and/or heteronuclear metal complexes with interesting ste- reochemistry[5, 6]. In addition, these metal complexes can be used for biological modeling applications, catalysis, design of molecular ferromagnet and mate- rials chemis…  相似文献   

20.
1 INTRODUCTION Transition-metal thiolato complexes have been of interest for the simulation of many metallo- enzymes where the thiolato group mimics the ligation of cysteinyl residues in proteins. Numerous complexes of transition elements with 1,2-bidentate oxothiolate ligands have been prepared[1~4]. Re- cently, we have studied a few transition metal complexes of 2-mercaptopyridine N-oxide (Hmpo) as bactericidal and antifungal reagents[5~7]. Although Hmpo exhibits unusual versatility…  相似文献   

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