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1.
1 INTRODUCTION The Schiff base ligands have been used to provide a stereochemically rigid ligand framework in homogenous precatalysts of some metals, such as salen Cr catalysts in asymmetric ring-opening re- action of epoxide[1] and salen Al in ring-opening polymerization of lactide and related cyclic esters[2]. Recently, it was reported that the bidentate Schiff base complexes of early and late transition metals can be served as promising alternatives to metal- locene catalysts for th…  相似文献   

2.
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   

3.
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   

4.
1 INTRODUCTION The chemical behavior of metal complexes with Schiff base ligand has attracted much attention be- cause of their catalytic activity in some industrial[1, 2] and biochemical processes[3~5]. As some metal com- plexes have shown the catalytic activity in some polymerization reactions[2, 6], we are recently inte- rested in polymerizartion of organo-silicon com- pounds catalyzed by Schiff base complexes of tran- sition metals. A series of Schiff base complexes have been prepare…  相似文献   

5.
1 INTRODUCTION The complexes of amino acid Schiff base have attracted considerable attention because of their bio- activities[1, 2]. Taurine is a special amino acid in be- ings, and recently the complexes of taurine conden- sation salicylaldehyde Schiff …  相似文献   

6.
1 INTRODUCTION It is well known that lanthanide metals are quite oxophilic and the oxygen-stabilized organolanthanide complexes are tractable for exploring their physical and chemical properties. Organolanthanide complexes involving -diketonato chelate ligands have been largely prepared and characterized[1~5]. The Schiff base complexes are some of the most important stereochemical models in transition metal coordination chemistry; however, the organolanthanide Schiff base complexes are …  相似文献   

7.
1 INTRODUCTION Schiff base ligands have been studied for a longtime due to the instant and enduring popularity fromtheir easy synthesis and versatility complexes. Theyplay an important role in the development of coor-dination chemistry as well as inorganic biochemistry,catalysis, optical materials and so on[1, . Consider- 2]able attention has been focused on the syntheses andstructures of copper(II) and nickle(II) complexes.The nickel complexes with multidentate Schiff baseligands have …  相似文献   

8.
1 INTRODUCTION The transition-metal Schiff base complexes have attracted much attention due to their beautiful struc- tures, multifunctions like catalysis[1~3] and materials science[4~6]. Recently, some Schiff base complexes based on guanidinate ligands have been explored[7~9], and most of them were synthesized by stepwise reactions. Due to the steric and electrical flexibility and abundant donor functionality of the guanidinate species, the ligand may adopt various coordination modes.…  相似文献   

9.
1 INTRODUCTION Schiff bases and their metal complexes are useful reagents in organic synthesis[1], and they have exhi- bited some biological activities as anticancer and antitumor drugs[2]. The crystal structures and physi- cal and chemical properties of many Schiff bases and their transition metals complexes have been re- ported[3~5]. Further interest in the coordination che- mistry of nickel(II) arises from the role of these complexes in several catalytic reactions, such as electrocat…  相似文献   

10.
1 INTRODUCTION Schiff base complexes containing sulfur and com- plexes of amino acid Schiff bases[1~5] have recently aroused increasing interest because of their antiviral, anticancer and antibacterial activities. Taurine, an amino acid containing sulfur, is indispensable to human beings and has important physiological func- tions. Recently, we have found that the Shiff base derived from taurine has manifold coordination modes[4~10]. Aromatic-ring stacking interaction is an important …  相似文献   

11.
A new Schiff base compound, 2-hydroxybenzoic acid [1-(3,5-dibromo-2-hydroxy- phenyl) methylidene]hydrazide methanol (C14H10Br2N2O3·CH3OH), has been synthesized by the condensation of equimolar 3,5-dibromosalicylaldehyde and 2-hydroxybenzoic acid hydrazide in a methanol solution. The compound was characterized by elemental analysis, IR spectra, and single- crystal X-ray diffraction. The compound consists of a Schiff base moiety 2-hydroxybenzoic acid [1-(3,5-dibromo-2-hydroxyphenyl)methylidene]hydrazide and a lattice methanol molecule. The crystal belongs to the monoclinic system, space group P21/n with a = 7.183(1), b = 15.673(2), c = 15.001(2) , β = 98.345(2)o, Z = 4, V = 1670.9(4) 3, Dc = 1.773 g/cm3, Mr = 446.10, λ(MoKα) = 0.71073 , μ = 4.872 mm-1, F(000) = 880, R = 0.0458 and wR = 0.0963. A total of 3445 unique reflections were collected, of which 2236 with I > 2σ(I) were observed. As expected, the molecule adopts a trans configuration about the C=N double bond. The two benzene rings are nearly coplanar (mean deviation from the combined plane is 0.061(4) ), with the dihedral angle of 7.9(3)o. The preliminary biological tests show that the compound has moderate antibacterial activities.  相似文献   

12.
The title compound C6H4(C7H5N2)2 was prepared by the condensation of o-phenylenediamine with o-phthalic acid and characterized by elemental analysis, IR, UV and ^1H NMR spectra, and its structure was determined by single-crystal X-ray diffraction,showing the compound molecule belongs to (72 point group. A ID chain structure was formed by the intermolecular hydrogen bonds (N(2)H…N(I)).  相似文献   

13.
A new quinazolinone compound 2,3-dihydro-2-(2-hydroxyphenyl)-3-phenylquinazolin-4(IH)-one 3 ([C2oH16O2N2]-C2H5OH, Mr = 362.42) and compound 2-(2-hydroxybenzylidene-amino)-N-phenyl-benzamide 2 (C2oH16O2N2, Mr = 316.34) were prepared from a precursor of 2-amino-N-phenyl-benzamide 1 (C13H12ON2, Mr = 212.25). Compound 3 was characterized by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic,space group Pbca with a = 1.2889(11), b = 1.6170(14), c = 1.7729(15) nm, V= 3.695(6) nm^3, Z= 8, F(000) = 1536, Mr = 362.42, Dc = 1.303 g/cm^3, μ(MoKa) = 0.087 mm^-1, R = 0.0447 and wR= 0.0879. The crystal structure analysis indicates that the title compound has a two-dimensional network structure formed by hydrogen bonds and electrostatic interactions.  相似文献   

14.
3-(Pyrrole-2'-carboxamido)propanoic acid I has been synthesized from the reaction of β-alanine methyl ester with 2-trichloroacetylpyrrole followed by saponifying and acidating in 85.4% yield, and the crystal structure of 3-(pyrrole-2'-carboxamido)propanoic acid· (1/2)H2O (C8H11N2O3.5, Mr = 191.19) was obtained and determined by X-ray diffraction method. The crystal is of monoclinic, space group C2/c with a = 19.010(4), b = 8.3515(17), c = 13.788(3) (A), β = 125.88(3)°, V = 1773.6(6) (A)3, Z = 8, Dc = 1.432 g/cm3, λ = 0.71073 (A), μ-MoKα) = 0.114 mm-1 and F(000) = 768. The structure was refined to R = 0.0354 and wR = 0.0942 for 1642 observed reflections with I > 2σ(I). It is revealed that the title compound has one pyrrole ring and one propionic acid subchain linked by an amido bond at C(4), and there are 8 molecules of com- pound I and 4 crystal water molecules in each unit cell. The supramolecular layers are stabilized by the hydrogen bonds of N(2) H…O(2), N(1) H…O(4), O(4) H(1W)…O(2) and O(3) H…O(1).  相似文献   

15.
A novel compound N-(pyridine-2-methyl)-2-(4-chlorophenyl)-3-methylbutanamide, a racemic compound, has been synthesized with 2-(4-chlorophenyl)-3-methylbutyric acid and pyridin- 2-methylanamine as the raw materials, and its crystal structure (C17H19C1N2O, Mr = 302.79) was determined by single-crystal X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/n with a = 9.624(9), b = 23.14(2), c = 15.626(15)A, β = 106.199(14)°, V = 3342(5) A^3, Z = 8, Dc = 1.204 g/cm^3,μ = 0.23 mm^-1, F(000) = 1280, S = 1.032, R = 0.0681 and wR = 0.1508 for 6513 unique reflections (Rint = 0.0421) with 3375 observed ones. In the crystal structure, there are some intermolecular hydrogen bonds which stabilize the crystal structure. The preliminary bioassay shows that the title compound exhibits good antifungal activity against Botrytis cinerea, Gibberella zeae, Dothiorella gregaria and Colletotrichum gossypii.  相似文献   

16.
1 INTRODUCTION Recently, compounds containing pyrazole, imida- zole, triazole (including benzotriazole), pyridine, tetrazole and indole have attracted much interest because of their fungicidal activity, plant-growth regulating activity and antibacterial activity[1~3]. Schiff bases also constitute a good type of biolo- gically active substructures[4~7]. Studies of pyri- dine Schiff base-type fungicides have been repor- ted[8]. However, some structures of pyridine com- pounds containing h…  相似文献   

17.
1INTRODUCTIONDiphenylcarbazideisanartificialelectrondonormaterialusedfrequentlyinanalyticalchemi-stryforcalorimetricdeterminationofchromiumandasensitivereagentformetalions(mercuryandcadmium)[1].Ithasvariousapplications,especiallyinthefieldsofbiophysicsandmicrobiology.Withthehelpofexogenouselectrondonors,diphenylcar-bazidephotointheactivatedsitesontheelectrontransferchainweredelineated[2].Diphenylcarbazideisalsoanartificialdonorduringchargeseparationinthephotochemicalreactions[3]andphotosy…  相似文献   

18.
Two new schiff base N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene)-1,3-propanediamine (1) and N,N'-bis((2-phenyl-2H-1,2,3-triazol-4-yl)methylene) -1,4-butanediamine (2) were synthesized by condensation of 2-phenyl-1,2,3-triazole-4-carboxaldehyde with diamine, and characterized by elemental analysis, IR, IH NMR and MS spectra. Their crystal structures were determined by X-ray single crystal diffraction. Both crystals belong to the monoclinic system, space group P21/c. For compound 1(C21H20N8, Mr=384.45): a = 16.314(3), b =5.7168(11), c = 21.316(4) A, β = 105.3(2)°, Z = 4, V = 1917.6(7) A^3, De =1.332 g/cm^3, F(000) = 808,μ = 0.086 mm 1, R = 0.0533 and wR = 0.1460; for compound 2 (C22H22N8, Mr=398.48): a = 8.6156(17), b = 5.2964(11), c = 22.665(5)A, β = 100.54(3)°, Z = 2, V = 1016.8(4) A^3, De= 1.302 g/cm^3, F (000) = 420, μ = 0.083 mm^-1, R = 0.0373 and wR = 0.1155. Based on the crystal data, quantum chemistry calculation was performed on the two title compounds by means of Gaussian 98 program. The molecular orbital energies and atomic net charges population were obtained. Furthermore, we antilyzed their active atoms. The investigation can serve as a theoretical guide to study the synthesis and activity of the title compounds.  相似文献   

19.
1 INTRODUCTION Halometallates are the particularly suitable systems for designing the construction of unusual low-dimensional structural archetypes, from which peculiar electronic, thermal, catalytic and magnetic properties can arise. The syntheses of th…  相似文献   

20.
<正> The title compound,C17H24N3O4PS(Mr = 405. 42) ,is a new compound of six-membered benzoheterocycle in which the five atoms N(1),C(1),C(11),C(16) andN(2) are coplanar with the and groups in trans-cross conformations. The crystal belongs to triclinic system,space group P1,with cell parameters a = 8. 580(2),b = 10.015 (4),c= 11. 896 (4) A ,α= 90. 65(3) ,β= 105. 70(3). γ= 89. 52(3)% V = 983. 9 A3,Z=2,Dx = 1. 37g/cm3. The final refinement converged with R=0. 074,Rw = 0. 090.  相似文献   

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