Clarification of Dynamic Behavior of Metal Ions in Solution and Development of Dynamic Analytical Chemistry

溶液中金属离子动态行为的澄清和动态分析化学的发展

基本信息

批准号：
10440221
负责人：
FUNAHASHI Shigenobu
金额：
$ 7.3万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

项目摘要

We can expect the enhancement of the selectivity and sensitivity in analysis by introducing the axis of time. We believe that a key point of the clarification of the mechanisms and reactivities of the reactions in solution is to detect and analyze the reaction intermediates and transition states. Our purpose is to develop the so-called dynamic Analytical Chemistry. We systematically pursued the mechanistic study on the reactions concerning metal ions in solution for Analytical Chemistry.(1) The relation between the solvation structures of metal ions and their reactivities has been clarified based on the following results : (a) the solvation structures of metal ions determined by EXAFS technique, (b) the kinetics and mechanism of the solvent exchange determined by NMR technique, and (c) the transition states of the water exchange on the transition metal (II) ions evaluated by the ab initio molecular orbital method.(2) The solvent, chelate, and pressure effects for the formation of the m … More etal complexes of ligands with stereochemical character have been clarified based on the following mechanisms : (a) the mechanism for the formation and deprotonation of the sitting-atop complexes, (b) the mechanism for the metal ion incorporation of the polyol complexes of boric acid, (c) the cyclopalladation mechanism, and (d) the mechanism for complexation of beryllium (II) ion in non-aqueous solution.(3) The outer-sphere electron transfer reactions between metal (II/III) complexes have been systematically investigated where the structural rearrangement in the inner-sphere is the rate-determining step, and the so-called gated mechanism has been clarified in detail.(4) We pursued the methodology for dynamic analytical chemistry. Detection and analysis of the unstable reaction intermediates produced during reactions have been performed. We developed a time-resolved stopped-flow EXAFS instrument, a spectrophotometric cell and a stopped-flow apparatus for supercritical carbon dioxide, and a high-frequency resonance spectrometer. Less

通过引入时间轴，我们可以期望提高分析的选择性和灵敏度。我们认为，阐明溶液中反应的机理和反应性的关键是检测和分析反应中间体和过渡态。我们的目的是发展所谓的动态分析化学。我们最终对溶液中金属离子的反应机理进行了研究。(1)金属离子的溶剂化结构与其之间的关系。基于以下结果阐明了反应性：（a）通过 EXAFS 技术测定的金属离子的溶剂化结构，（b）通过 NMR 技术测定的溶剂交换动力学和机制，以及（c）水的过渡态通过从头算分子轨道法评估过渡金属 (II) 离子的交换。(2) 溶剂、螯合物和压力对形成具有立体化学特征的配体金属络合物的影响基于以下机制已得到澄清：(a) 坐在顶部配合物的形成和去质子化机制，(b) 硼酸多元醇配合物的金属离子掺入机制，(c) 环钯化机制，和（d）非水溶液中铍（II）离子的络合机理。（3）系统地研究了金属（II/III）络合物之间的外层电子转移反应，其中内层的结构重排是速率决定步骤，所谓的门控机制已被详细阐明。(4)我们探索了动态分析化学过程中产生的不稳定反应中间体的检测和分析方法。我们开发了时间分辨停流 EXAFS 仪器、超临界二氧化碳分光光度计和停流装置以及高频共振光谱仪。