镍, 锌, 钴(II)-N-(间甲苯基)亚氨基二乙酸-氮三乙酸的量热研究

使用改进的RD-1型热导式量热计测量了镍(II), 锌(II),钴(II)-N-(间甲苯基)亚氨基二乙酸-氮三乙酸三元配合物的生成焓, 发现其大小按金属离子来说符合Irving-William序列。利用配体的多环水化结构等讨论了该三元配合物的生成焓和相应的二元配合物的生成焓, 同时求得了上述三元体系的热力学参数, 指出上述三元体系的生成熵是导致这些三元体系具有较大稳定性的根本原因。     

配合物的生成热与配位体的质子化热之间的直线焓关系——Ⅲ、铜(Ⅱ)-2,2-联吡啶-, 铜(Ⅱ)-邻菲咯啉-N-(间位取代苯基)氨基乙酸三元体系

前文曾报道了铜(Ⅱ)-N-(间位取代苯基)氨基乙酸二元配合物体系的直线焓关系,本文报告铜(Ⅱ)-2,2′-联吡啶,铜(Ⅱ)-邻菲咯啉-N-(间位取代苯基)氨基乙酸三元体系的量热研究。结果表明,在此类三元配合物的生成热与第二配体的质子化热之间亦存在良好的直线焓关系:ΔH_M=Q-βΔH_(L1)。此外,我们还计算了三元配合物的生成熵变和第二配体的质子化熵变,发现两者之间也呈相当好的线性关系,即直线熵关系。     

配合物稳定性与配位体酸碱强度之间的直线自由能关系 IX: Cu(II)[或Ni(II)]-2,2'-联吡啶-N,N'-双(对位取代苯基)乙二胺三元配合物体系的研究

报导了以2,2'-联吡啶为第一配体, N,N'-双(对位取代苯基)乙二胺为第二配体的Cu(II)、Ni(II)三元配合物稳定性的研究, 发现三元配合物的稳定性与第二配体的碱性强度之间存在线性自由能关系.     

配合物的稳定性与配位体酸碱强度之间的直线自由能关系VII,铜(II)-杂环芳香碱-氨基酸三元体系

在25.0±0.2℃,I=0.1mol.dm^-^3NaClO~4存在下,用pH法测定了铜(II)-α,α'-联吡啶-N-(对取代苯基)氨基乙酸(ρ-RPhG;R=CH~3O,CH~3,H,Cl)、铜(II)-邻菲罗啉-N-(间取代苯基)氨基乙酸[在30%(ν/ν)乙醇中]、铜(II)-α,α'-联吡啶-α氨基酸、铜(II)-邻菲罗啉-α-氨基酸[在水溶液中]等三元配合物的生成常数,发现这四个体系三元配合物的稳定性分别与其第二配位体的碱性强度之间存在直线自由能关系,应用ΔlogK~M、logX值讨论了三元配合物的稳定性,在铜(II)-邻菲罗啉-N-(间取代苯基)氨基乙酸三元配位体系中再次发现ΔlogK~m,logX值与pK~2值呈现良好的线性关系。     

配合物生成反应速率常数与配体酸离解常数之间的直线自由能关系 V. 铜(II)-2,9-二甲基邻菲罗啉与α-氨基酸和N-苯基乙二胺生成三元配合物的动力学研究

应用温度跃迁装置和断流分光光度计分别研究了铜(II)-2,9-二甲基邻菲罗啉与α-氨基酸和N-苯基乙二胺在25℃、0.1mol·dm^-^3KNO3水溶液中的生成反应动力学。实验结果表明在铜(II)-2,9-二甲基邻菲罗啉-α-氨基酸三元配合物的生成速率常数与配体α-氨基酸的酸离解常数之间存在着如下的直线自由能关系: logkf=2.84+0.53pK2。根据Eigen机理讨论了铜(II)-2,9-二甲基邻菲罗啉-N-苯基乙二胺三元配合物的生成反应动力学。     

配合物生成反应速率常数与配体酸离解常数之间的直线自由能关系 V. 铜(II)-2,9-二甲基邻菲罗啉与α-氨基酸和N-苯基乙二胺生成三元配合物的动力学研究

应用温度跃迁装置和断流分光光度计分别研究了铜(II)-2,9-二甲基邻菲罗啉与α-氨基酸和N-苯基乙二胺在25℃、0.1mol·dm^-^3KNO3水溶液中的生成反应动力学。实验结果表明在铜(II)-2,9-二甲基邻菲罗啉-α-氨基酸三元配合物的生成速率常数与配体α-氨基酸的酸离解常数之间存在着如下的直线自由能关系: logkf=2.84+0.53pK2。根据Eigen机理讨论了铜(II)-2,9-二甲基邻菲罗啉-N-苯基乙二胺三元配合物的生成反应动力学。     

L-苏氨酸二元和三元配合物的PH电位法研究

本文报道了L-苏氨酸同Cu(II),Zn(II),Fe(II),Mn(II),Ca(II),Mg(II),Ni(II),Cd(II)的二元及三元配合物的pH电位法研究.电位滴定数据是使用MINIQUAD和ESTA计算机程序处理的.在每个体系中确定了最佳配合物粒子模型,并测定了在生理条件下(温度为37±0.1℃离子强度为150mmol.dm^-3NaCl)的稳定常数.结果表明在铜配合物中Cu,Thr.His混配配合物是与Cu(His)~2^-同样重要的配合物,因此需要重新计算在血浆中铜在这些配合物中的分布.虽然苏氨酸可以看作为三齿配位体,但本工作的结果并无证据支持羟基参与配位,然而在Cd-The-His体系中,Cd.Thr.His同它的1:2母体二元配合物相比表现了显著的稳定性,这可能显示了不同的配位状况.但这一点有待于进一步证实.     

邻苯二酚-3,6-二甲撑亚氨基二乙酸的酸离解平衡及其与碱土金属、锰(II)、镉(II)、锌(II)、钴(II)、镍(II)、铜(II)、铁(II)、钍(IV)及铀酰离子配合物稳定性的研究

本文报道用PH滴定法测得KNO3水溶液中邻苯二酚-3,6-二甲撑亚氨基二乙酸(CBMIDA, H6L)的六级酸解离常数及CBMIDA的镁(II)、钙(II)、锶(II)、钡(II)、镍(II)、锌(II)、钴(II)、镉(II)、锰(II)、铜(II)、铁(II)、钍(IV)和铀酰离子的配合物稳定常数及配合物的质子化常数. 讨论了CBMIDA的逐级酸离解的动态平衡机理以及金属离子与CBMIDA形成的各种配合物的配位形式.     

P[(NH3)5CoimM(tren)](ClO4)4·2H2O[M=Cu(II), Zn(II)]的合成、表征及咪唑桥的断裂

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。     

三元配合物Er(Et2dtc)3(phen)的热化学性质

三元配合物Er(Et2dtc)3(phen)的热化学性质;Er(Et2dtc)3(phen); 微量热法; 热动力学; 恒容燃烧能; 标准摩尔生成焓     

镍、锌、钴(II)-N-(对位取代苯基)亚氨基二乙酸的量热

使用改进的RD-1型热导式量热计测定了镍（Ⅱ）-、钴（Ⅱ）-、锌（Ⅱ）-N-（对位取代苯基）亚氨基二乙酸等三个二元配位体系的生成热．这些配合物的生成热不仅与配体的质子化热之间存在着线性关系，而且它们的大小按金属离子来说是完全符合Irving-Williams序列的，并利用配体的多环水化结构解释了N-（取代苯基）亚氨基二乙酸根质子化热呈正值（吸热）的实验事实。     

Complexes of vitamin B6—XV quaternary complexes involving pyridoxamine,glycine and ethylenediamine with Co(II), Ni(II), Cu(II) and Zn

The formation constants of quaternary Co(II), Ni(II), Cu(II) and Zn complexes comprising pyridoxamine as a first, glycine as a second and ethylenediamine as a third ligand were determined by pH-metric titration at I = 0.5 M NaNO₃ and 30°. The complexes are generally protonated in which the ligands may act as bidentate as well as monodentate. The formation of the quaternary species is discussed in relation to pertinent binary and ternary species. The validity of the Van Panthaleon van Eck equation was also tested.     

Potentiometric study of the Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes with 3-hydroxy-2-naphthalene carboxylic acid

Formation constants of Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) complexes with 3-hydroxy-2-naphthalene carboxylic acid have been determined potentiometrically in a 50% (v/v) dioxane—water solution at 25°C and 0.2 M KNO₃. Experimental data are analysed using several computer programs. The obtained values for the log of the formation constant of the first 1 : 1 (metal : ligand) complex with the different metals are: Co 7.9, Ni 7.1, Cu 10.44, Zn 7.8 and Cd 7.3. The log of the formation constant for the 1 : 2 copper complex is 18.20. It is to be noted that Ni(II) yields a 1 : 1 complex weaker than expected from the Irving—Williams series.     

Electrometric Studies on the Ternary Complexes of M(II) With Chlorpromazine and Some Amino Acids

 The stability constants for the binary M(II)- chlorpromazine hydrochloride (CPZ) and the ternary complexes M(II)-chlorpromazine-amino acid, have been studied using pH-measurements. The amino acids (aa) are: glycine, glutamic acid, histidine and the metal ions are: Cu(II), Zn(II), Co(II), Ni(II) and UO₂(II). All experiments were carried out in the presence of 0.1 mol dm⁻³ KNO₃. The resulting stability constants of the binary and the ternary complexes were compared. It was observed that the stability of the ternary complexes-except for glutamic acid – are lower than of the binary ones. Received October 22, 1998. Revision March 14, 1999.     

Spectral,thermal and magnetic investigations of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 4-methylphthalates

Conditions for the preparation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) 4-methylphthalates were investigated and their composition, solubility in water at 295 K and magnetic moments were determined. IR spectra and powder diffraction patterns of the complexes prepared with molar ratio of metal to organic ligand of 1.0:1.0 and general formula: M [ CH₃C₆H₃(CO₂)₂]·nH₂o (n=1-3) were recorded and their decomposition in air were studied. During heating the hydrated complexes are dehydrated in one (Mn, Co, Ni, Zn, Cd) or two steps (Cu) and next the anhydrous complexes decompose to oxides directly (Cu, Zn), with intermediate formation of carbonates (Mn, Cd), oxocarbonates (Ni) or carbonate and free metal (Co). The carboxylate groups in the complexes studied are mono- and bidentate (Co, Ni), bidentate chelating and bridging (Zn) or bidentate chelating (Mn, Cu, Cd). The magnetic moments for paramagnetic complexes of Mn(II), Co(II), Ni(II) and Cu(II) attain values 5.92, 5.05, 3.36 and 1.96 M.B., respectively. This revised version was published online in July 2006 with corrections to the Cover Date.     

New Complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) with 3,3-dimethylglutaric Acid

Conditions for the preparation of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)3,3-dimethylglutarates were investigated and their quantitative composition, solubility in water at 293 K and magnetic moments were determined. IR spectra and powder diffraction patterns of the complexes prepared with general formula MC₇H₁₀O₄⋅nH₂O (n=0−2) were recorded and their thermal decomposition in air were studied. During heating the hydrated complexes of Mn(II),Co(II), Ni(II) and Cu(II) are dehydrated in one step and next all the anhydrous complexes decompose to oxides directly (Mn, Co, Zn) or with intermediate formation free metal (Ni,Cu) or oxocarbonates (Cd). The carboxylate groups in the complexes studied are bidentate. The magnetic moments for the paramagnetic complexes of Mn(II), Co(II), Ni(II) and Cu(II)attain values 5.62, 5.25, 2.91 and 1.41 M.B., respectively. This revised version was published online in August 2006 with corrections to the Cover Date.     

Binary and Ternary Complexes Involved in the Systems Methioninehydroxamic Acid - Glycylglycine - Ni(II) or Cu(II) Ions

The formation constants of binary and ternary complexes involved in the systems methioninehydroxamic acid (MX), glycylglycine (GG) and Cu(II) or Ni(II) were determined by pH-metric titration in aqueous solution at an ionic strength (I)= 0.15 M NaCl) and T = 25°C. Ternary species of the type (MX : GG : Ni(II) or Cu(II) : H) = (1 : 1 : 1 : r), (2 : 1 : 1 : r) and (1 : 2 : 1 : r) exist in the pH range ～3 to ～10. Differential pulse polarography (DPP) was used to follow complex formation and to study the reduction properties of these metal ions in the presence of MX, and GG. The metal oxidation states were more stabilized in the ternary systems than in the binary systems except for a few Ni(II) systems. Spectral studies in the UV-Vis-nIR were used to monitor the presence of ternary species in the Ni(II) and Cu(II) systems. In addition, EPR studies were also used to record the magnetic properties of the binary and ternary species in the Cu(II) systems.     

Structural, spectroscopic and thermal characterization of 2-tert-butylaminomethylpyridine-6-carboxylic acid methylester and its Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and UO(2)(II) complexes

Fe(III), Co(II), Ni(II), Cu(II), Zn(II) and UO(2)(II) complexes with the ligand 2-tert-butylaminomethylpyridine-6-carboxylic acid methylester (HL(2)) have been prepared and characterized by elemental analyses, molar conductance, magnetic moment, thermal analysis and spectral data. 1:1 M:HL(2) complexes, with the general formula [M(HL(2))X(2)].nH(2)O (where M = Co(II) (X = Cl, n = 0), Ni(II) (X = Cl, n = 3), Cu(II) (grey colour, X = AcO, n = 1), Cu(II) (yellow colour, X = Cl, n = 0) and Zn(II) (X = Br, n = 0). In addition, the Fe(III) and UO(2)(II) complexes of the type 1:2 M:HL(2) and with the formulae [Fe(L(2))(2)]Cl and [UO(2)(HL(2))(2)](NO(3))(2) are prepared. From the IR data, it is seen that HL(2) ligand behaves as a terdentate ligand coordinated to the metal ions via the pyridyl N, carboxylate O and protonated NH group; except the Fe(III) complex, it coordinates via the deprotonated NH group. This is supported by the molar conductance data, which show that all the complexes are non-electrolytes, while the Fe(III) and UO(2)(II) complexes are 1:1 electrolytes. IR and H1-NMR spectral studies suggest a similar behaviour of the Zn(II) complex in solid and solution states. From the solid reflectance spectral data and magnetic moment measurements, the complexes have a trigonal bipyramidal (Co(II), Ni(II), Cu(II) and Zn(II) complexes) and octahedral (Fe(III), UO(2)(II) complexes) geometrical structures. The thermal behaviour of the complexes is studied and the different dynamic parameters are calculated applying Coats-Redfern equation.     

Acid equilibria of semi-methylthymol blue and formation constants of cobalt(II), nickel(II), copper(II) and zinc(II) complexes with semi-methylthymol blue

Potentiometric and spectrophotometric studies on Semi-Methylthymol Blue (SMTB or H(4)L) have been performed. The acid-base and Co(II), Ni(II), Cu(II) and Zn(II)-ligand reaction stoichiometries were determined, and the formation constants of the corresponding proton and metal complexes, and the molar absorptivities were calculated. Evidence was found for the formation of 1:1 Co(II), Ni(II) and Cu(II) complexes, and 1:1 and 1:2 Zn(II) complexes. Cu(II) formed the hydroxo-complex, Cu(OH)L(3-), but no hydroxo-complexes of the other metal ions were observed. Suggestions are made concerning the probable structure of the complexes.     

Structural and thermal decomposition characteristics of mixed-ligand complexes of Cu(II), Ni(II), Co(II) and Zn(II)

Mixed-ligand complexes of Cu(II), Ni(II), Co(II) and Zn(II) with 8-hydroxyquinoline and thiophene-2-carboxylic acid as two different ligands, have been isolated in pure state. The formation of these complexes has been inferred potentiometrically. The isolated complexes have been characterized by their elemental analyses, IR and electronic spectra, conductivity and magnetic measurements. Solid state dehydration of the hydrated complexes and subsequent decomposition of the anhydrous complexes have been studied by simultaneous DTA and TG techniques. The thermal stability order of the hydrated compounds is Cu>Co>Ni>Zn, but in the decomposition process the trend observed is Co>Zn>Ni>Cu. Some parameters like activation energy and order of reaction for each process have been computed.