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1.
Organic second-order nonlinear optical (NLO) materials have been extensively studied for their potential application involving telecommunications, optical information process and storage1. It has been found that the molecular hyperpolarizability of the NLO chromophores varys dramatically depending upon the donor-acceptor abilities as well as the nature of the conjugated bridge.Carbazole molecule has an isoelectronic structure of diphenylamine, and thus the introduction of electron acceptor (…  相似文献   

2.
1 INTRODUCTION The nature and topography of the herbicide binding site in the reaction center of photosystem Ⅱ (PSⅡ) have been the subject of intense interest for many years. Among several commercially important herbicides with different structures such as atrazine and polypeptide of the PSII reaction center[1], the cyanoacrylates with general structure 1 have proved hightly potent and useful as probes[2, 3] of the receptor because their activities as inhibitors of photosynthetic ele…  相似文献   

3.
Recently, much effort has been made in the development of generally applicable organic synthesis of 5-alkyloxy-2(5H)-furanones due to their essential structure entities in the synthesis of some biologically active natural products and their application as useful intermediates in organic synthesis1. Their reactions such as Michael addition, Diels-Alder reaction and photocatalyzed conjugate addition have been studied extensively2-4.However, Michael addition reaction of Grignard reagents to 5-m…  相似文献   

4.
1 INTRODUCTION Macrocyclic ligands and their metal complexes have received much attention due to their applications in ion transport, ion separation and as models in biomimic researches[1~7]. The synthetic methods of macrocyclic ligands and their metal complexes are mainly divided into three kinds[8]. The first one is synthesizing free ligand, then forming the metal complexes; the second is template synthesis; and the third is synthesizing the end-off or side-off precursor ligand, then c…  相似文献   

5.
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 as the materials to produce pharmaceutical, essences, biochemicals, etc. It has been found that a great deal of pyrrole derivatives present bioactivities, such as antitumor and antiviral activities[2~5]. Thus, due to the interest in exploring the syntheses of potential bioactive materials which contain pyrrole ring andna…  相似文献   

6.
1 INTRODUCTION In our previous study [1], we found that 1, 3, 2-thiazaphospholidine-4-thione 2-sulfide deriva- tives possessed various bioactivities such as herbicidal, antiviral, fungicidal activity, Which the is strongly held our interest to exploit new method for the synthesis of such phosphorohe- terocycles and investigate their biological activities. Different method for the preparation of 1, 3, 2-thiazaphospholidine-4-thione (one) 2-sulfides have been reported [2~4]. According to …  相似文献   

7.
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   

8.
1 INTRODUCTION σ-Alkynyl complexes of platinum have attracted considerable attention over the last few years not only for their structural aspect and reactivity[1~5], but also for their role as building blocks for molecular materials with interesting properties[6~10]. These complexes are usually stabilized by neutral ligands, such as tertiary phosphines PR3, diphosphines, and so on. However, as far as we know, similar platinum acetylide compounds containing the chiral diphos- phine liga…  相似文献   

9.
蔡跃鹏  康北笙 《结构化学》2001,20(4):262-265
INTRODUCTIONCrystal engineering and supramolecular chemistry aimed at developing systems to perform optical, magnetic and electronic functions as well as intercalation systems for ion- or molecule-exchange and catalytic properties are some of the most attractive research areas in present years, and much progress has been achieved in both theoretical studies and their applications as new materials[1]. One of the most remarkable development in crystal engineering may be that it is possible t…  相似文献   

10.
Polymer-supported reagents and catalysts have attracted considerable attention as they offer alternative methods to separate and reuse expensive and often toxic chemicals1. Traditionally, the polymer-supported chiral catalysts are prepared by anchoring highly enantioselective monomeric catalysts to flexible and sterically irregular polymer supports. Because of the stereo-irregularity and flexibility of the traditional polymeric chiral catalysts, their catalytic sites do not have well-defined…  相似文献   

11.
The thermal behaviors of the complexes of Cu(DMTZB)4X2 (DMTZB=3,3‘-dimethyl-1-(1H-1,2,4-triazol-1-yl)-2-butanone, X=NO3 or ClO4) and Cu(DMTZB)2 X2 (X=Br or Cl) in a nitrogen atmosphere were studied under the non-isothermal conditions by simultaneous TG-DTG-DSC, EDS and elemental analysis techniques. The resuits showed that their decomposition proceeded in three different ways mainly depending on the anions in the molecules. The heat effect associated with the decomposition step of DMTZB molecules was also different. The decomposition mechanisms and the kinetic parameters of DMTZB were determined and calculated by jointly using four methods, which showed that its pyrolysis was controlled by D3 mechanism but with different activation energies and pre-exponential factors for different complexes.  相似文献   

12.
The synthesis and characterization of Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Pd(II) and UO2(II) chelates of 1-(2-thiazolylazo)-2-naphthalenol (TAN) were reported. The dissociation constants of the ligand and the stability constants of the metal complexes were calculated pH-metrically at 25 degrees C and 0.1 M ionic strength. The solid complexes were characterized by elemental and thermal analyses, molar conductance, IR, magnetic and diffuse reflectance spectra. The complexes were found to have the formulae [M(L)2] for M = Mn(II), Co(II), Ni(II), Zn(II) and Cd(II); [M(L)X].nH2O for M = Cu(II) (X = AcO, n = 3), Pd(II) (X = Cl, n = 0) and UO2(II) (X = NO3, n = 0), and [Fe(L)Cl2(H2O)].2H2O. The molar conductance data reveal that the chelates are non-electrolytes. IR spectra show that the ligand is coordinated to the metal ions in a terdentate manner with ONN donor sites of the naphthyl OH, azo N and thiazole N. An octahedral structure is proposed for Mn(II), Fe(III), Co(II), Ni(II), Zn(II), Cd(II) and UO2(II) complexes and a square planar structure for Cu(II) and Pd(II) complexes. The thermal behaviour of these chelates shows that water molecules (coordinated and hydrated) and anions are removed in two successive steps followed immediately by decomposition of the ligand molecule in the subsequent steps. The relative thermal stability of the chelates is evaluated. The final decomposition products are found to be the corresponding metal oxides. The thermodynamic activation parameters, such as E*, delta H*, delta S* and delta G* are calculated from the TG curves.  相似文献   

13.
Microcalorimetric measurements were made on copper(II) and nickel(II) complexes of the Schiff base (L) derived from 2-(2-aminophenyl)benzimidazole and salicylaldehyde. The complexes were of the general type MX2L2 with M = Cu or Ni, and X = Cl, Br, NO3 or ClO4. The enthalpies of decomposition of the solid complexes to solid products, MX2 and L, were derived. Despite showing some variation depending on the anion, the average binding enthalpy of the ligand to nickel was 47.5 ± 7.3 kJ mol−1, greater than that to copper, 16.8 ± 3.5 kJ mol−1 by 30.7 ± 8.1 kJ mol−1.  相似文献   

14.
Copper(II) and cadmium(II) complexes of 5-(4'-derivatives phenyldiazo)-3-phenyl-2-thioxo-4-thiazolidinone (HLn) were prepared, their compositions and physicochemical properties were characterized by elemental analysis, magnetic suseptibility measurements, and infrared, electronic spectra. The novel complexes have the stoichiometric formulae [Cu(HLn)(OAc)n(H2O)(X)] (OAc = acetate, X = H2O or acetate) and [Cd(L)(OAc)(H2O)], respectively. Elemental analysis and IR spectra denote, that two types of complexes with different octahedral and tetrahedral structure for Cu(II) and Cd(II) ions. I.R. spectra show that the ligand is monobasic/neutral bidentate forming thereby a six-membered chelating ring and concomitant formation of an intramolecular hydrogen bond. The stoichiometeries of these complexes were determined conductometrically and indicated the formation of 1:1 and 1:2 (metal:ligand) complexes.  相似文献   

15.
Cheng JW  Zheng ST  Ma E  Yang GY 《Inorganic chemistry》2007,46(25):10534-10538
A new series of heterometallic lanthanide(III)-copper(I) coordination polymers Ln2(bdc)2(ina)2(H2O)2Cu x X (Hina = isonicotinic acid; H2bdc = 1,2-benzenedicarboxylic acid; Ln = Eu (1), Sm (2), Nd (3), X = ClO4-; Ln = Nd (4), X = Cl-) have been hydrothermally synthesized in the presence/absence of HClO4. Both compounds are isostructural and contained two distinct units of 2D Ln-bdc layers and linear [Cu(ina)2]-. The linear [Cu(ina)2]- complexes act as pillars and further link the Ln-bdc layers resulting in four heterometallic metal-organic frameworks, which represent the first pillared-layer 3d-4f framework with two distinct types of channels along the b and c axes. The compounds can be specified by the Schl?fli symbol (47.63)(47.68) as a novel 3D (5,6)-connected net. Furthermore, the IR, TGA, PXRD, and UV-vis spectral and luminescent properties of 1-4 were also studied.  相似文献   

16.
The reactions of cyclodiphosphazane cis-[tBuNP(OC6H4OMe-o)]2 (1) with 2 equiv of CuX in acetonitrile afforded one-dimensional Cu(I) coordination polymers [Cu2X2{tBuNP(OC6H4OMe-o)}2]n (2, X = Cl; 3, X = Br; 4, X = I). The crystal structures of 2 and 4 reveal a zigzag arrangement of [P(mu-N)(2)P] and [Cu(mu-X)(2)Cu] units in an alternating manner to form one-dimensional Cu(I) coordination polymers. The reaction between 1 and CuX in a 2:1 ratio afforded mononuclear tricoordinated copper(I) complexes of the type [CuX{(tBuNP(OC6H4OMe-o))2}2] (5, X = Cl; 6, X = Br; 7, X = I). The single-crystal structures were established for the mononuclear copper(I) complexes 5 and 6. When the reactant ratios are 1:1, the formation of a mixture of polymeric and mononuclear products was observed. The Cu(I) polymers (2-4) were converted into the mononuclear complexes (5-7) by reacting with 3 equiv of 1 in dimethyl sulfoxide. Similarly, the mononuclear complexes (5-7) were converted into the corresponding polymeric complexes (2-4) by reacting with 3 equiv of copper(I) halide under mild reaction conditions.  相似文献   

17.
The reaction between 2-hydrazinopyridine and ethylisothiocyanate produced 4-ethyl-1-(pyridin-2-yl) thiosemicarbazide (HEPTS). Its reaction with copper fluoride, chloride, bromide, acetate, nitrate, perchlorate, sulfate, carbonate, hydroxide and copper metal produced 15 Cu(II) complexes. The copper metal is easily oxidized in aqueous-ethanol solution of HEPTS giving [Cu(2)(EPTS)(H(2)O)(3)(OH)(3)]EtOH. Different complexes for the same anion were synthesized by controlling the heating time. Characterization by elemental, thermal, magnetic and spectral (electronic, IR, mass and ESR) studies showed the formation of mono-, di-, tri- and tetra nuclear complexes. The room temperature solid state ESR spectra of the complexes show an axial spectrum with d(x)(2)-y(2) ground state, suggesting distorted tetragonal geometry around Cu(II) center. The kinetic and thermodynamic parameters for the different decomposition steps in the complexes were calculated. HEPTS and its Cu(II) complexes showed high activity against gram negative bacteria; [Cu(3)(EPTS)(2)(EtOH)(2)Br(4)] has more activity.  相似文献   

18.
The preparation and characterization of 2-(2-benzimidazolylazo)-4-acetamidophenol (BIAAP) complexes are reported. Different physico-chemical methods like IR, Magnetic, solid reflectance spectra and molar conductance, were used to investigate the structure of BIAAP complexes. In particular, the thermal decomposition of Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes of BIAAP is studied in nitrogen atmosphere. All the complexes do not contain coordinated water molecules but contain (2-4) water molecules of crystallization. The water molecules were removed in a single step. The complexes of Co(II) and Ni(II) ions exhibited a phase transition and the decomposition or combustion of BIAAP occurred in the second and subsequent steps. The final decomposition products were identified by mass spectrometry as the corresponding metal oxides or carbonate. The activation thermodynamic parameters, such as, energy of activation, enthalpy, entropy and free energy change of the complexes were evaluated and the stabilities of the thermal decomposition of the complexes are discussed. From the kinetic point of view, it is found that the thermal stability of the complexes follows the order Ni(II) > Cu(II) > Zn(II) > Fe(III) > Co(II) > Cd(II).  相似文献   

19.
Mn(II), Co(II), Ni(II) and Cu(II) chelates with3-phenyl-4-(p-methoxyphenylazo)-5-pyrazolone have been synthesized and were characterized by elemental and thermal analyses as well as by IR, UV-VIS, 1HNMR, conductometric and magnetic measurements. The first stage in the thermal decomposition process of these complexes shows the presence of water of hydration, the second denotes the removal of the coordinated water molecules. The final decomposition products were found to be the respective metal oxides. The data of the investigated complexes suggest octahedral geometry with respect to Co(II) 1:1, tetrahedral for Ni(II) 1:1and 2:3; square planar for Cu(II) 1:1 and 2:3; the complexes with no coordinated water molecules (2:3) Co(II) and Mn(II) complexes are tetrahedral. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
Reaction of Kpmf (pmf(-) = anion of N,N'-bis(pyrimidyl-2-yl)formamidine, Hpmf) with divalent copper salt CuX2 afforded the linear trinuclear complexes of the type [Cu3(pmf)4](X)2 (X = BF4, 1; NO3, 2; ClO4, 3), while reaction of Kpmf with monovalent copper salt CuX gave the linear tetranuclear complexes of the type Cu4(pmf)4X2 (X = Cl, 4; Br, 5). The copper atoms of complexes 1-5 are helically bridged by four pmf(-) ligands, resulting in three different coordination modes for the pmf(-) ligands. In complexes 1-3, one pmf(-) ligand adopts a new coordination mode with the two amine nitrogen atoms chelating to the central copper atom, while the other three feature chelation by one pyrimidyl and one adjacent amine nitrogen atoms. The Cu(II)...Cu(II) distances are 2.729(2) and 2.825(2) A for 1, 2.762(1) and 2.832(1) A for 2 and 2.732(1) and 2.827(1) A for 3. In complexes 4 and 5, the pmf(-) ligands are coordinated to the copper atoms in tetradentate fashion with each nitrogen atom coordinating to one Cu atom. The Cu...Cu distances are 2.580(1) and 2.549(1) A for 4 and 2.582(1) and 2.561(1) A for 5. Antiferromagnetic interactions between the copper ions are observed with calculated g and J values of 2.03(1) and -188(2) cm(-1) for 1, 2.09(1) and -268(3) cm(-1) for 2, and 2.09(1) and -486(2) cm(-1) for 5. By comparing the magnetic data it can be shown that the bonding mode of the pmf(-) ligand is one of the important factors in determining the strengths of the Cu...Cu interactions in linear trinuclear and tetranuclear copper complexes.  相似文献   

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