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1.
合成了三个24元大环双铜(II)配合物作为SOD模拟物, 配体由2, 6-二乙酰基吡啶与3-氧杂戊烷1, 5-二胺缩合而成, 以SCN^-, N~3^-, im^-桥联, 其中前面两个桥联双铜(II)配合物是新配合物。用多种物理方法进行了表征, 并用EPR和电子光谱研究了桥基为im^-的配合物与N~3^-, SCN^-, F^-和Br^-的键合。其中N~3^-发生轴向配位, SCN^-使im^-断裂, 与SOD的键合作用类似, F^-, Br^对模拟物无明显作用。  相似文献   

2.
本文合成了两个新的异双核咪唑桥联配合物[(NH3)5CoimM(tren)](ClO4)4·2H2O[M=Cu(II), Zn(II); im=咪唑基], 用热重差热、反射光谱、ESR等手段进行表征, 证实咪唑桥的存在, 用PH法结合计算机拟合, 定量地模拟了异双核配合物中咪唑桥的断裂过程, 表明在水溶液中, 金属-咪唑键首先从非钴(III)端断裂。  相似文献   

3.
以2-甲基喹 啉为配体合成了五种含有阴离子ClO~4^-或BF~4^-的铜(II)配合物, 利用元素分析、红外光谱、电子光谱、电导、热重谱、ESR谱及变温磁化率的测定推测了配合物的结构, 提出双核铜配合物中含有直线型单氧桥Cu(II)-O-Cu(II)键的可能构型。  相似文献   

4.
本文合成了两个新的异双核咪唑桥联配合物[(NH3)5CoimM(tren)](ClO4)4·2H2O[M=Cu(II), Zn(II); im=咪唑基], 用热重差热、反射光谱、ESR等手段进行表征, 证实咪唑桥的存在, 用PH法结合计算机拟合, 定量地模拟了异双核配合物中咪唑桥的断裂过程, 表明在水溶液中, 金属-咪唑键首先从非钴(III)端断裂。  相似文献   

5.
白令君  李盛荣  王耕霖 《化学学报》1989,47(12):1174-1177
以2-甲基喹 啉为配体合成了五种含有阴离子ClO~4^-或BF~4^-的铜(II)配合物, 利用元素分析、红外光谱、电子光谱、电导、热重谱、ESR谱及变温磁化率的测定推测了配合物的结构, 提出双核铜配合物中含有直线型单氧桥Cu(II)-O-Cu(II)键的可能构型。  相似文献   

6.
廿员大环双核铜(II)配合物的合成和对超氧歧化酶的摸拟   总被引:5,自引:0,他引:5  
罗勤慧  沈孟长  彭庆芸  高伟  张正 《化学学报》1990,48(12):1164-1170
本文合成了六个新的廿员大环双核铜(II)配合物作为Cu,Zn-SOD模拟物, 其配体是用2,6-二甲酰基吡啶与1,3一丙二胺缩合而成, 以SCN,Cl-Br-,I-,N3-,OH-桥联, 用多种物理方法进行表征, 并用核黄素光照法研究与O2-反应的动力学, 结果表明, 反应速率常数大约在107mol-1.Clm3,S-1其中以SCN为桥的配合物速率常数最高,而含N3-桥的最低, ESR谱研究结果表明前者与O2-为可逆的催化反应, 后者为不可逆的氧化还原反应, 这种情况与作者曾研究过的二乙酰基吡啶缩丙二胺合铜配合物一致, N3-桥对配合物的阻化作用与N3-对SOD的阻化作用类似。  相似文献   

7.
本文合成了六个新的廿员大环双核铜(II)配合物作为Cu,Zn-SOD模拟物, 其配体是用2,6-二甲酰基吡啶与1,3一丙二胺缩合而成, 以SCN,Cl-Br-,I-,N3-,OH-桥联, 用多种物理方法进行表征, 并用核黄素光照法研究与O2-反应的动力学, 结果表明, 反应速率常数大约在107mol-1.Clm3,S-1其中以SCN为桥的配合物速率常数最高,而含N3-桥的最低, ESR谱研究结果表明前者与O2-为可逆的催化反应, 后者为不可逆的氧化还原反应, 这种情况与作者曾研究过的二乙酰基吡啶缩丙二胺合铜配合物一致, N3-桥对配合物的阻化作用与N3-对SOD的阻化作用类似。  相似文献   

8.
罗勤慧  杨升  沈孟长  张正 《化学学报》1990,48(4):355-359
由4-叔丁基2,6-二甲酰基苯酚与4-正己基-3-氨基硫脲缩合, 合成了"大乌"配体(H3BB), 它与Cu(II)、Ni(II)、Co(II)、Pb(II)、Cd(II)生成五种电中性的可溶性"大乌"配合物, 除Co(II)配合物外, 其余四种均为乙氧基桥联的双核配合物, 配体是将4-叔丁基2,6-二羟甲基苯酚用MnO2在室温下直接氧化, 得到4-叔丁基-2,6-二甲酰基苯酚, 然后再与4-正己基-3-硫代氨基脲缩合而得, 该反应步骤较少, 产量较高, 优于前人结果。用IR、UV等方法对配合物进行了表征, 并用Evans的核磁共振法研究了吡啶与Ni2BB(OEt)在轴向的作用和配合物两中心原子间的作用。这五种配合物中, 有趣的是Ni2BB(OEt)呈顺磁性, 本文对其原因作了探讨。  相似文献   

9.
本文合成了六个4, 4'-联吡啶桥联配合物: [M(TTA)~2(μ-4, 4'-bipy)]~n,[M=Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II); TTA=噻吩甲酰三氟丙酮], 经元素分析、IR、 1^H NMR和晶体结构分析, 确定配合物具有一维无限链状结构。Mn(II)配合物的晶体属三斜晶系, 空间群PI, 晶胞参数: a=0.9549(2),b=0.9600(3), c=1.1556(3)nm, α=65.99(3), β=83.96(4), γ=68.89(3)°;V=0.9017(4)nm^3; Z=1; Dc=1.417g.cm^-3; μ=5.3cm^-1; F(000)=393; 最终R=0.067。Mn(II)处于畸变八面体配位环境中。由Cu(II)配合物的ESR谱近似了分子轨道系数和键合参数。Mn(II), Cu(II)配合物的变温磁化率表明, 金属离子间磁行为服从Curie定律。  相似文献   

10.
本文合成了两个新的双核配合物, [Cu(sampu)Ni(L)2], sampn^4^-表示N,N'-1,2-丙二水杨酰胺阴离子, L表示2,2-联吡啶(bpy)或1,10-菲咯啉(phen),经元素分析, IR和电子光谱等方法已推定配合物具有酚氧桥结构和Cu(II)及Ni(II)的配位环境分别为平面四方及八面体构型, 配合物的变温磁化率已测(4-300K), 其数值用最小二乘法和从自旋哈密顿算符H=-2JS1S2导出的磁方程拟合, 求得交换参数为J=-1.90cm^-^1(pby)和J=1.68cm^-^1(phen), 表明两个Cu(II)-Ni(II)双核配合物中有弱的反铁磁自旋交换相互作用。  相似文献   

11.
A series of metal complexes were achieved from the metal-assisted solvolysis reaction of di-pyridylketone azine (dpka). The tetranuclear nickel cluster , [Ni(2)[dpk(O)(OH)][dpk(O)(OCH(3))](N(3))(2)](2), is centrosymmetric with a central core described as an edge-shared triangle core. Neighboring Ni(II) ions are alternately bridged by (micro(2)-N(3), micro(3)-O) and (micro(2)-O, micro(3)-O) double bridges. Complex , [Cu(4)[dpk(O)(OCH(3))](4)(N(3))(2)](CuCl(2))(2) contains a tetranuclear cluster and two identical [CuCl(2)]M(-) anions. The tetranuclear structure has two crystallographically imposed twofold axes, in which the four copper ions are arranged to be rhombic shape. The neighboring copper(ii) ions along the lateral are bridged by single micro(2)-O from the ligand dpk(O)(OCH(3)) and the short diagonal copper ions are bridged by two symmetric end-on azides. In dinuclear Cu(ii) complex [Cu(2)[dpka(OCH(2)CH(3))]Cl(2)](ClO(4)) (3), the metal centers are coordinated in a planar configuration and bridged by a -N-N- bridge. It is also observed that the Cl atom coordinated to one Cu(II) center is also weakly coordinated to another inversion related Cu(II) to generate a centrosymmetric dimer. The metal centers in one-dimensional polymeric Cu(ii) complex [Cu(2)[dpka(OCH(3))](N(3))(2)(ClO(4))](n) (4), however, are bridged by a -N-N- bridge and an end-to-end azide bridge, alternately. Magnetic susceptibility measurements indicate that shows ferromagnetic interaction within the tetranuclear cluster, and that displays moderately strong antiferromagnetic interaction (J = -56.7 cm(-1)) for the bis(micro-N(3)) bridge. For compound , it shows strong antiferromagnetic coupling (J = -286 cm(-1)) between the intradinuclear Cu(II) ions mediated by the single N-N bridge and negligible magnetic interactions between the adjacent dinuclear Cu(II) ions mediated by the single end-to-end azide bridge. The mechanism of the metal-assisted solvolysis reaction was also discussed.  相似文献   

12.
含Cu咪唑桥联异多核配合物的合成、表征及ESR研究   总被引:1,自引:0,他引:1  
陈东  唐雯霞  戴安邦 《化学学报》1990,48(6):547-553
用具有低自旋d^6构型的[(NH3)5MIm]^2^+, [(en)2Co(Im)2]^+(M=Co, Rh; Im^-为咪唑基)为配体与配位未饱和的含Cu单核配合物作用, 定向合成了八种新的咪唑桥联含Cu异双核、异三核和异五核配合物。对它们进行了元素分析、差热失重分析、摩尔电导测定及反射光谱研究, 确证了配合物的组成及分子中咪唑桥的存在, 通过对各配合物的ESR谱测定, 得到了它们的自旋Hamilton参数和键参数, 讨论了配合物的成键性质。  相似文献   

13.
A tetra-nuclear, star-shaped hetero-metallic copper(II)-manganese(II) complex, [{CuL(H(2)O)}(2)(CuL)Mn](ClO(4))(2) (1) has been synthesized by reacting the "complex as ligand" [CuL] with Mn(ClO(4))(2) where H(2)L is the tetradentate di-Schiff base derived from 1,3-propanediamine and 2-hydroxyacetophenone. Upon treatment with the polyatomic anions azide, cyanate, or thiocyanate in methanol medium, complex 1 transforms into the corresponding trinuclear species [(CuL)(2)Mn(N(3))(2)] (2), [(CuL)(2)Mn(NCO)(2)] (3) and [(CuL)(2)Mn(NCS)(2)] (4). All four complexes have been structurally and magnetically characterized. In complex 1 the central Mn(II) ion is encapsulated by three terminal [CuL] units through the formation of double phenoxido bridges between Mn(II) and each Cu(II). In complexes 2-4 one of the CuL units is replaced by a couple of terminal azide, N-bonded cyanate or N-bonded thiocyanate ions respectively and the central Mn(II) ion is connected to two terminal Cu(II) ions through a double asymmetric phenoxido bridge. Variable temperature magnetic susceptibility measurements show the presence of moderate ferrimagnetic exchange interactions in all the cases mediated through the double phenoxido bridges with J values (H = -JS(i)S(i + 1)) of -41.2, -39.8 and -12.6 cm(-1) (or -40.5 and -12.7 cm(-1) if we use a model with two different exchange coupling constants) for the tetranuclear MnCu(3) cluster in compound 1 and -20.0, -17.3 and -32.5 cm(-1) for the symmetric trinuclear MnCu(2) compounds 2-4. These ferrimagnetic interactions lead to spin ground states of 1 (5/2 - 3*1/2) for compound 1 and 3/2 (5/2 - 2*1/2) for compounds 2-4.  相似文献   

14.
Zhao JP  Hu BW  Zhang XF  Yang Q  El Fallah MS  Ribas J  Bu XH 《Inorganic chemistry》2010,49(24):11325-11332
Five new isomorphic three-dimensional (3D) heterometallic 3d-3d azide complexes, [CuNi(1-x)Co(x)(N(3))(2)(isonic)(2)](∞) (x = 0 for 1, x = 0.3 for 2, x = 0.5 for 3, x = 0.6 for 4, and x = 1 for 5), were obtained by assembling Cu(II), M(II) (Ni(II) and Co(II)), azide, and pyridyl carboxylate in hydrothermal condition. The 3D structure can be described as end on (EO) azide and syn,syn carboxylates mixed bridged alternate Cu-M chains linked by the pyridyl groups. Dominant ferromagnetic interactions were observed between the Cu(II) and M(II) ions in the chains. At low temperature diverse magnetic phenomena were presented in those complexes. As the Ni(II) ions were replaced by Co(II) ions with large anisotropy, the magnetism of the complexes change gradually from metamagnet to single-chain magnet (SCM)-like behaviors.  相似文献   

15.
某些芳香族羟肟一过渡金属配合物的红外光谱   总被引:1,自引:0,他引:1  
周澄明  陈星  袁承业 《化学学报》1983,41(7):623-629
The preparation and infrared spectroscopic studies of coordination compounds of salicylaldoxime, 2-hydroxy-acetophenone oxime, 2-hydroxy-benzophenone oxime and 2-hydroxy-4-methoxy-benzophenone oxime with copper (II), nickel (II), cobalt (II) and iron (II) have been described. The frquency of the C=N stretching vibration is usually higher in the complex than that in the ligand. The higher the frequency of the C=N vibration is, the larger the stability constant of the complex will be, but there is no quantitative relationship. In the case of complexes of salicylaldoxime with Cu, Ni, Co and Fe, &CC=N values are correlated linearly with the ionization potentials of the central metal ions. The frequency of the OH stretching vibration is closely related to the geometric configuration of the complex. Thus aromatic hydroxyoximes form coordination compound with Co (II) and Fe (II) with cis configuration possessing six membered stronger hydrogen bonding ring. This is indicated in the infrared spectra by the complete absence of the absorption band due to the OH stretching vibration, or by the appearance of an extremely broad and flat band of very low intensity. However, Cu (II) or Ni (II) complex possesses trans configuration with five membered hydrogen-bonding bridge showing characteristic OH absorption band in the infrared region. The &COH of complex investigated is closely related to the polar nature of the substituents on the benzene ring. By examining the spectra of Cu-63 and Cu-65 complexes with 2-hydroxy-4(5)-substituted benzophenone oximes, the characteristic frequencies of M -- O and M -- N in the far infrared region were assigned for a series of aromatic hydroxyoxime-transition metal complexes.  相似文献   

16.
The dinuclear Cu2+ and Zn2+ as well as the mixed Cu2+-Zn2+ complexes of a 5,5'-pentaazaterpyridinophane ligand (L) are able to incorporate imidazolate (Im-) as a bridging ligand. The crystal structure of [Cu(2)L(Im)(Br)(H2O)](CF(3)SO(3))(2).3H2O (1) shows one copper coordinated by the three pyridine nitrogens of the terpyridine unit, one nitrogen of the imidazolate bridge (Im-) and one bromide anion occupying the axial position of a distorted square pyramid. The second copper atom is coordinated by the remaining imidazolate nitrogen, the three secondary nitrogens at the centre of the polyamine bridge and one water molecule that occupies the axial position. Magnetic measurements have been performed in the 2.0-300.0 K temperature range. Experimental data could be satisfactorily reproduced by using an isotropic exchange model H = -JS(1)S(2) with J = -52.3 cm(-1) and g = 2.09. Potentiometric studies have provided details of the speciation and stability constants for the mixed Cu2+-L-HIm, Zn2+-L-HIm (HIm = imidazole) and Cu2+-Zn2+-L-HIm systems. The apparent stability constant obtained at pH = 9 for the addition of imidazole to the dinuclear Cu2+ complexes is one of the highest so far reported (log K = 7.5). UV-Vis spectroscopy and paramagnetic NMR data show that imidazole coordinates to the Cu2+ ions as a bridging imidazolate ligand from pH 5 to 10. Electrochemical reduction of the Cu2+-Zn2+-L complex occurs in two successive one-electron per copper ion quasi-reversible steps. The formal potential of the Cu2+-Zn2+-L/Cu+-Zn2+-L couple is close to that of SOD. The IC50 values measured at pH 7.8 by means of the nitro blue tetrazolium method show significant SOD activity for the dinuclear Cu2+ complexes (IC50 = 2.5 microM) and moderate activity for the Cu2+-Zn2+ mixed systems (IC50 = 30 microM).  相似文献   

17.
The reaction of N,N-bis(2-pyridylmethyl)-2-aminoethanol (bpaeOH), NaSCN/NaN(3), and metal (M) ions [M = Mn(II), Fe(II/III), Co(II)] in MeOH, leads to the isolation of a series of monomeric, trimeric, and tetrameric metal complexes, namely [Mn(bpaeOH)(NCS)(2)] (1), [Mn(bpaeO)(N(3))(2)] (2), [Fe(bpaeOH)(NCS)(2)] (3), [Fe(4)(bpaeO)(2)(CH(3)O)(2)(N(3))(8)] (4), [Co(bpaeOH)(NCS)(2)] (5), and [Co(3)(bpaeO)(2)(NO(3))(N(3))(4)](NO(3)) (6). These compounds have been investigated by single crystal X-ray diffractometry and magnetochemistry. In complex 1 the Mn(II) is bonded to one bpaeOH and two thiocyanate ions, while in complex 2 it is coordinated to a deprotonated bpaeO(-) and two azide ions. The oxidation states of manganese ions are 2+ for 1 and 3+ for 2, respectively, indicating that the different oxidation states depend on the type of binding anions. The structures of monomeric iron(II) and cobalt(II) complexes 3 and 5 with two thiocyanate ions are isomorphous to that of 1. Compounds 1, 2, 3, and 5 exhibit high-spin states in the temperature range 5 to 300 K. 4 contains two different iron(III) ions in an asymmetric unit, one is coordinated to a deprotonated bpaeO(-), an azide ion, and a methoxy group, and the other is bonded to three azide ions and two oxygens from bpaeO(-) and a methoxy group. Two independent iron(III) ions in 4 form a tetranuclear complex by symmetry. 4 displays both ferromagnetic and antiferromagnetic couplings (J = 9.8 and -14.3 cm(-1)) between the iron(III) ions. 6 is a mixed-valence trinuclear cobalt complex, which is formulated as Co(III)(S = 0)-Co(II)(S = 3/2)-Co(III)(S = 0). The effective magnetic moment at room temperature corresponds to the high-spin cobalt(II) ion (~4.27 μ(B)). Interestingly, 6 showed efficient catalytic activities toward various olefins and alcohols with modest to excellent yields, and it has been proposed that a high-valent Co(V)-oxo species might be responsible for oxygen atom transfer in the olefin epoxidation and alcohol oxidation reactions.  相似文献   

18.
Wen HR  Wang CF  Song Y  Zuo JL  You XZ 《Inorganic chemistry》2005,44(24):9039-9045
One-dimensional chiral copper(II) and manganese(II) coordination polymers with single asymmetric end-to-end (EE) azide bridges, [Cu(R-L)2(N3)]n(ClO4)n (1), [Cu(S-L)2 (N3)]n(ClO4)n (2), [Mn(R-L)2(N3)]n(ClO4)n (3), and [Mn(S-L)2(N3)]n(ClO4)n (4) (R-L or S-L = R- or S-pyridine-2-carbaldehyde-imine), have been synthesized, using azide ions as bridging groups and chiral Schiff bases as auxiliary ligands, and characterized. The crystal structure determination of complexes 1 and 2 reveals the formation of one-dimensional chiral chains, in which the central Cu(II) ion is six-coordinate in the form of an elongated octahedron. Complex 3 consists of chiral helical polymeric chains, in which the central Mn(II) has a slightly distorted octahedral geometry. They all crystallize in the chiral space group P2(1). Complexes 1 and 2 are rare examples that exhibit ferromagnetic interaction between copper(II) ions through the single end-to-end azido bridge. Fitting the susceptibility data for 1 using a 1D uniform chain model led to the parameters J = 0.70(3) cm(-1), g = 2.06(2), and zj' = 0.07(2) cm(-1). The magnetic studies on 3 and 4 show that there is weak antiferromagnetic coupling between the manganese(II) ions.  相似文献   

19.
4,4'-联吡啶、吡嗪和咪唑桥联铜、镍配合物的合成和磁性   总被引:3,自引:1,他引:3  
合成了六个含氮杂环桥联配合物: [Ni(salal)2(4,4'-bipy)]n、[Ni(Et-dtp)2(4,4'-bipy)]n、[Cu(acac)2(4,4'-bipy)]n、[Cu(TTA)2(pyz)]n、[Cu(TTa)(Im)]n和[Cu(Im)2]n, 用元素分析、IR、MS、ESR和热重分析对它们的结构和性质作了表征。吡嗪配合物的晶体结构显示, 吡嗪配位于拉伸八面体的轴向位置, 桥联Cu(TTA)2形成一维无限链状结构。变温磁化率表明, 4,4'-联吡啶和吡嗪配合物的磁性遵从Curie-Weiss定律, 分子内没有明显的磁交换作用。咪唑配合物中存在着较强的反铁磁性交换作用, 磁交换常数分别为-75和-107cm^-^1。对4,4'-联吡啶、吡嗪和咪唑传递磁交换的性质作了讨论。  相似文献   

20.
Two transition metal complexes with azide and 3,4-di(2′-pyridyl)-1,2,5-oxadiazole (dpo), [Cu2(dpo)2(N3)4] (1), and [Mn(dpo)2(N3)2] (2), have been synthesized and characterized by single-crystal X-ray diffraction. The Cu(II) complex is binuclear with double end-on (EO) azido bridges, in which each Cu(II) ion assumes a distorted square pyramidal geometry, and each EO azido bridge adopts a quasi-symmetric fashion. In contrast, the Mn(II) complex is mononuclear, in which the Mn(II) ion is ligated by two dpo ligands and two terminal azide ions, with a distorted octahedron geometry. Magnetic studies on the Cu(II) complex revealed that the double EO azido bridge mediates ferromagnetic coupling with J=12.8 cm−1.  相似文献   

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