确定金属酶及模拟络合物中金属离子氧化态的一种方法——键价和分析

在生物化学领域中弄清金属酶活性中心的结构和氧化态是至关重要的。“键价和分析”是根据金属 配体键长数据确定固体中金属离子氧化态的一种方便可行的方法 ,它已用于金属蛋白、金属酶以及高温超导体中金属氧化态的指派。本文拟介绍该方法的要点及其实际应用。     

Synthesis, characterization and magnetism of binuclear cobalt (II) complexes bridged by tetracarboxylato groups

Three new binudear cobalt (II) complexes with extended te-tracarboxylato- bridge have been synthesized and characterized, namely [Co2 (PMTA) (bpy)4] (1), [Co2(PMTA)-(phen)4] (2) and [Co2(PMTA) (NO2phen)4] (3), where PMTA represents the tetraanion of pyroniellitic acid, and bpy, phen, NO2-phen denote 2,2'-bipyridine, 1,10-phenan-throline; 5-nirto-1, 10-plienanthroline, respectively. Based on elemental analyses, molar conductivity measurements, IR and electronic spectra studies, it is proposed that these complexes have PMTA-bridged structures and consist of two cobalt (II) ions, each in a distorted octahedral environment. These complexes were further characterized by variable temperature magnetic susceptibility measurements (4-300 K) and the observed data were successfully simulated by the equation based on the spin Hamiltonian operator, giving the exchange integral J = - 1.02 cm-1 for 1, J = -1.21 cm-1 for 2 and J = - 1.18 cm-1 for 3, respectively. These results revealed the operation of antiferromagneti     

桥联异双核配合物的设计和合成

异双核配合物在生命科学和分子磁性材料研究领域起着重要作用，但它的合成却难度较大。本文介绍四种常用、有效的合成方法。     

混合桥基双核配合物中的轨道互补与反互补效应

在混合桥基的双核体系中,金属中心的磁轨道的线形组合可与相同对称性的桥基最高占据轨道(HOMO'S)相互作用.如果两种桥联配体稳定同一磁轨道组合,则称它们以互补方式起作用;反铁磁偶合就会被加强.反之,如果桥联配体稳定不同的磁轨道组合,则称它们以反互补方式起作用;这将减小反铁磁偶合.本文就互补和反互补效应以及相关的磁学知识做一简要概述.     

具有强反铁磁相互作用的线性三核铜（Ⅱ）配合物的合成与磁性

具有强反铁磁相互作用的线性三核铜（Ⅱ）配合物的合成与磁性缪明明，廖代正，姜宗慧，王耕霖（南开大学化学系，天津３０００７１）关键词草氨酸根，Ｃｕ（Ⅱ）－Ｃｕ（Ⅱ）－Ｃｕ（Ⅱ），反铁磁偶合多原子桥联配合物的研究［１，２］将有助于了解通过多原子桥联配体控制...     

草酸根桥联的不对称双核铜(Ⅱ)和铜(Ⅱ)-锌(Ⅱ)配合物的合成与磁性

本文合成了一组新的不对称的双核配合物,[Cu_2(C_2O_4)_2terp]和〔Cu Zn(C_2O_4)_2terp〕(图1),terp表示联三吡啶。配合物〔Cu_2(C_2O_4)2terp〕的变温磁化率已测,其数值已用最小二乘法与Bleaney-Bowers方程拟合,求得交换积分J=-47.20cm~(-1)。文中还用Kahn理论解释了这种较弱的反铁磁自旋交换作用。     

Schiff 碱双核配合物的磁性及催化性能的研究

This paper reports the catalytic properties of “porphyrin-like” Schiff base mononuclear complexes MH₂L {M=Mn(Ⅱ), Fe(Ⅲ)Cl, Cr(Ⅲ)Cl, Cu(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ); L=bis[N, N′-ethylene-2, 2′-(phenylmethylene)bis(3,4-dimethylpyrrole-5-aldimino)]} and dinuclear complexes MnML [M=Mn(Ⅱ), Fe(Ⅲ)Cl, Cr(Ⅲ)Cl, Cu(Ⅱ), Co(Ⅱ), Ni(Ⅱ), Zn(Ⅱ)] for cyclohexane monooxygenation with PhIO and magnetic properties of the dinuclear complexes. The magnetic investigations (4～300 K) of the dinuclear complexes revealed that their antiferromagnetic spin exchange with J ranged from -10.49 to -0.482 cm^-1 except MnZnL and antiferromagnetic spin exchange decreased in the following order: Mn^Ⅱ-Cu^Ⅱ > Mn^Ⅱ-Ni^Ⅱ > Mn^Ⅱ-Mn^Ⅱ > Mn^Ⅱ-Fe^Ⅲ > Mn^Ⅱ-Co^Ⅱ > Mn^Ⅱ-Cr^Ⅲ. The results of catalyzed oxidation of cyclohexane indicated that the catalytic property of the dinuclear complex was better than that of the corresponding mononuclear complex. It was found that there was the synergism decreased in the order: Mn-Fe > Mn-Cr > Mn-Cu > Mn-Mn > Mn-Co> Mn-Ni > Mn-Zn. It seems that this synergism increases with the increase of the number of unpaired d electrons and the magnetic exchange between the two metals in these dinuclear complexes.     

钒（Ⅳ）与N，N，N＇，N″，N″─五苯并咪唑甲基二乙三胺多核配合物合成、ESR和生物活性

合成了两种新的Ｎ，Ｎ，Ｎ＇，Ｎ″，Ｎ″─五苯并咪唑甲基二乙三胺ＶＯ（Ⅱ）多核配合物并进行了元素分析、ＩＲ、ＵＶ─ｖｉｓ、ＥＳＲ等表征。求得了配合物的自旋Ｈａｍｉｌｔｏｎ参数，两配合物中Ｖ（Ⅳ）的电子环境差别较大。体外抗癌活性和农药活性测定结果表明配合物具有一定生物活性。     

含水杨酰胺合铜(Ⅱ)酸根的双核铜(Ⅱ)配合物的合成和磁性

本文合成了2个新型双核铜(Ⅱ)配合物,[Cu(samen)Cu(NO_2-phen)]·H_2O和[Cu(sampn)Cu(NO_2-phen)]·2H_2O,samen~(4-),sampn~(4-)和NO_2-phen分别表示N,N′-乙二水杨酰胺根阴离子,N,N′-1,2-丙二水杨酰胺根阴离子和5-硝基-1,10-菲绕啉。经元素分析,IR,电子光谱等手段推知该类配合物具有酚氧桥及其Cu(Ⅱ)离子的配位环境为畸变四方构型。测得配合物的变温磁化率(4—300K),其数值已用最小二乘法与修正的Bleaney-Bowers方程拟合,求得交换积分,J=—63.0cm~(-1)(samen)和—46.5cm~(-1)(sampn),表明标题配合物中有反铁磁性超交换作用。