氯合间取代四苯基卟啉铁与咪唑类配体配位反应的热力学研究  

Thermodynamic Study of Coordination of Meso-substituted Iron(Ⅲ)Tetraporphyrin with Substituted Imidazoles

作　　者：陈红卫[1] 朱志昂[1] 阮文娟[1] 陈正华[1] 张智慧[1] 陈荣悌[1] 

机构地区：[1]南开大学化学系

出　　处：《高等学校化学学报》1996年第10期1608-1612,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金;天津自然科学基金

摘　　要：用紫外可见光谱法，在ＤＭＳＯ中测量了氯合间取代四苯基铁卟啉与多种咪唑类配体反应的平衡常数，研究了卟啉环上取代基、反应温度以及配体等因素对反应平衡常数的影响。利用温度系数法测定了反应体系的热力学函数ΔｒＨｍ和ΔｒＳｍ。The thermodynamics of axial coordination reaction of Fe(Ⅲ)T(m-X)PPCl(X= -CH3,-H,-OCH3,-Cl,-NO2)with ligands of the substituted imidazole(L=Im(imidazole),2-Melm(2-methylimidazole),GMZ(clotrimidazole),at different temperature in DMSO have been studied. Fe(Ⅲ)T(m-X)PPCl+Nl[Fe(Ⅲ)T(m-X)PPLn]+Cl-The standard equilibrium constant K and stoichiometric number n of reaction were measured by visible spectral techniques.The changes of standard molar enthalpyΔrHm and the changes of standard molar entropyΔrSmof reaction were obtained from the plots of lnK vs,1/T.The standard equilibrium constant K increases with the decrease of temperature,andΔrHm<0,ΔrSm<0.The steric and electronic effects of the three axial ligands on the reaction are compared.Hammett linear relationships didn't exist in the system of Fe(Ⅲ)T(m-X)PPCl with GMZ.This is because of steric effect of ligand GMZ on the reaction.

关 键 词：氯 甲苯基卟啉铁 咪唑 配位反应 平衡常数 

分 类 号：O614.811[理学—无机化学] O642.4[理学—化学]