摘要
金属离子与有机配体形成配合物的稳定性与金属离子的特性和有机配体的分子结构密切关系。为了探讨席夫碱与金属离子配位的稳定性规律,本文以二芳基希夫碱为模型配体化合物,选用部分过渡金属离子(Ni^2+、Mn^2+、Fe^3+、Cu^2+、Cr^3+)为配位对象,将金属离子的特性参数和配体中取代基X的电子效应参数Hammett常数作为变量,对模型化合物与金属离子形成的配合物的稳定常数logβ2进行定量构效关系研究,得到具有良好相关性的定量方程并通过实验验证了方程的可靠性。结果表明,金属离子的能量密度(XP/PM+)是影响配合物稳定性的主要因素;对同一金属离子,取代基的吸电子效应增强配合物的稳定性;而金属离子电荷Q和离子半径R需在一个合适的范围内,才利于配合物的稳定。
The stability of complexes formed by metal ions and organic ligands is closely related to the properties of metal ions and the molecular structure of ligands.To systematically investigate coordination stability of Schiff base with metal ions,bi-aryl Schiff bases were taken as the model compounds.The stability constant(logβ2)of complexes was quantified by some characteristic parameters of metal ions(Ni^2+、Mn^2+、Fe^3+、Cu^2+、Cr^3+)and Hammett constants of substituents on ligand.An equation with good correlation was obtained.And then,the reliability of the equation was verified by experiments.The result shows that the energy density(XP/PM+)of metal ions is the major factor affecting the stability of the complexes.For a same kind of metal ion,the electron-withdrawing effect of substituent enhanced the stability of the complex.While the charge Q and radius R of metal ions must be in a suitablerange,which is favorable to the stability of the complex.
作者
肖琰
曹晨忠
XIAO Yan;CAO Chen-zhong(School of resource Environment and Safety engineering,School of Chemistry and Chemical Engineering,Key Laboratory of Theoretical Organic Chemistry and Function Molecule,Ministry of Education,Hunan University of Science and Technology,Xiangtan 411201,China)
出处
《化学研究与应用》
CAS
CSCD
北大核心
2020年第5期782-788,共7页
Chemical Research and Application
基金
国家自然科学基金项目(21672058)资助。
