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1.
Jun JIA Xing Wang WANG Yi Li ZHAO Yu ZHU Jing Chao TAO* Department of Chemistry Zhengzhou University Zhengzhou Chemical Engineering Institute of Henan Province Zhengzhou 《中国化学快报》2004,15(3):292-295
Proteins containing dinuclear Cu (II), Zn (II) centers play paramount roles in biology1. As mimetic of metal-dependent esterase, dinuclear Cu (II) and Zn (II) complexes have received a great deal of attentions2~6. They are of interest in the field of biomimetic chemistry to provide an improved understanding of the function of the biological sites and as potential catalysts for substrate oxidations. Schiff base type polydentate ligands which contain centeral hydroxyl group have been wid… 相似文献
2.
Different Types of Nickel,Cobalt, and Manganese Complexes originating from 2‐Imidazolecarboxaldiimine of Triethylenetetraamine 下载免费PDF全文
The reactivity of the 2‐imidazolecarboxaldiimine of triethylenetetraamine (H2imida) towards divalent manganese, cobalt, and nickel ions differs. It forms a cationic nickel(II) complex by acting as a hexa‐dentate ligand, whereas the cobalt(II) complex formation took place by deprotonation of the H2imida forming a neutral complex with imida. Deprotonation of the ligand by H2imida by cobalt(II) ions caused quenching of the fluorescence emission at 312 nm, such a quenching effect was not observed with the nickel ions. On the other hand, a mononuclear manganese(II) complex of a new tetradentate ligand was formed by manganese(II) assisted intramolecular cyclization reactions of H2imida. 相似文献
3.
Ayako Harano 《Journal of organometallic chemistry》2011,696(1):61-6791
A new chiral N-heterocyclic carbene (NHC) ligand was designed. Thus, an efficient synthetic route to C2-symmetric bis(hydroxyamide)-functionalized benzimidazolium salts from chiral β-amino alcohols was developed. The combination of Cu(OTf)2 and the chiral azolium compound efficiently promoted the conjugate addition reaction of cyclic enone with dialkylzinc to give the corresponding adduct in good yield. Among a series of chiral NHC proligands, the functionalized benzimidazolium chloride possessing a tert-butyl group as a stereodirecting group was found to be the best choice of ligand. Under optimized reaction conditions, an excellent enantioselectivity (96% ee) was realized by allowing 2-cyclohepten-1-one to react with Bu2Zn at room temperature. 相似文献
4.
《Journal of Coordination Chemistry》2012,65(8):1272-1282
Two pyrazole-based polydentate ligands, 1,3-bis(5-methyl-3-phenylpyrazol-1-yl)-propan-2-ol (Hmppzpo) and 1,3-bis(5-methyl-3-p-isopropylphenylpyrazol-1-yl)-propan-2-ol (Hmcpzpo), have been synthesized. A third ligand, 1,3-bis(3,5-dimethylpyrazol-1-yl)-propan-2-ol (Hdmpzpo), has been synthetically modified. Seven new M(II) coordination compounds of general formula M2L2X2 (M?=?Zn, Ni; X?=?NO3 or ClO4; L?=?dmpzpo, mppzpo or mcpzpo) or MLX (M?=?Pd; L?=?dmpzpo; X?=?Cl) were synthesized and structurally characterized by elemental analysis and FT-IR analysis. The crystal structures of [Zn2(μ-dmpzpo-O,N,N′)2(NO3)2]?·?2H2O (1?·?2H2O), [Ni2(μ-dmpzpo-O,N,N′)2(CH3CN)2](ClO4)2 (2) and Pd(μ-dmpzpo-N,N′)Cl2 (4) were determined by single-crystal X-ray crystallography. The crystal structures show that complexes 1?·?2H2O and 2 are center-symmetric dinuclear compounds, with two metal ions bridged by two alkoxo groups and each metal ion with a distorted square-pyramidal environment. The palladium complex, 4, displayed square-planar coordination geometry around the Pd(II) ion with trans arrangement. 相似文献
5.
《Journal of Coordination Chemistry》2012,65(5):825-832
6.
《Journal of Coordination Chemistry》2012,65(8):1412-1422
A family of phenoxo-bridged heterometallic Schiff base trinuclear complexes, [Fe2LnL2(C3H7COO)(H2O)]·CH3OH·CH3CN·H2O (Ln = Sm, 1; Gd, 2; Tb, 3; Dy, 4) is reported. Those complexes were afforded by “one-pot” reaction of a polydentate Schiff base ligand 2-hydroxy-3-methoxy-phenylsalicylaldimine (H2L) with Fe(NO3)3·9H2O, Ln(NO3)3·6H2O and sodium butyrate (C3H7COONa) in a mixture of methanol and acetonitrile in the presence of triethylamine as a base. Single-crystal X-ray diffraction analysis reveals that the structures of the four complexes are isomorphic. In each complex, two anionic [FeL2]? units coordinate to the central lanthanide ion as a tetradentate ligand using its four phenoxo oxygens, forming a two-blade propeller-like molecular shape. Magnetic properties of 1–4 were investigated using variable temperature magnetic susceptibility, and weak ferromagnetic exchange between the FeIII and LnIII ions has been established for the Gd derivative. The Tb and Dy complexes show no evidence of slow relaxation behavior above 2.0 K. 相似文献
7.
Ján Labuda Pavol Tarapčík Adela Kotočová Jozef Šima 《Monatshefte für Chemie / Chemical Monthly》1992,123(8-9):693-699
Summary Half-wave potentials for a one-electron reduction of copper(II) complexes containing polydentate ligands can be calculated using the equationE
1/2=E
0(Cu2+/+)+
i
j
E
i where E
i are contributions related to the electronic and steric properties of the ligands. The values of 18 E
i contributions are presented and explained, and the effect of the solvents on the half-wave potentials is exemplified.Dedicated to Prof. Dr. Viktor Gutmann to his 70th birthday 相似文献
8.
Clément Camp 《Tetrahedron letters》2008,49(12):1979-1983
Two novel bifunctional chelating agents, which are bistriazole-based polyaminocarboxylic acids, have been designed and synthesised in high yields. An elegant synthetic approach using the Cu-catalysed azide-alkyne cycloaddition has been developed. This convenient route could be employed for the synthesis of a variety of polydentate bifunctional chelators. 相似文献
9.
D. Vaughan Griffiths Helen J. Groombridge Stephen P. Swetnam David C. York 《Tetrahedron》2005,61(19):4595-4600
The synthesis of a range of new phosphine-containing polydentate ligands has been achieved by addition of sulfur and nitrogen nucleophiles to dimethylvinylphosphine sulfide, followed by reduction of the resulting phosphine sulfides with lithium aluminium hydride. 相似文献
10.
Synthesis,Characterization, and Magnetic Properties of Iron Complexes Bearing Polydentate Nitrogen Ligands 下载免费PDF全文
Four iron complexes {[PhN(CH2)2NH(SiMe3)]4FeLi · Et2O ( 1 ), [PhN(CH2)3NSiMe3]2FeLi(Et2O) ( 2 ), [PhN(CH2)2NCH(Ph)NSiMe3]2FeLi(Et2O)2 ( 3 ), and [PhN(CH2)3NCH(Ph)NSiMe3]2FeLi(Et2O)2 ( 4 )} with polydentate nitrogen ligands were synthesized and structurally characterized by X‐ray crystallography. The X‐ray structures of complexes 1 – 4 show that they crystallize in three different systems. The magnetic properties of 1 – 4 were investigated. The magnetization trends of magnetic field intensity show the curves of Type‐S, illustrating those complexes 1 – 4 are superparamagnetic. 相似文献