对称及非对称卟啉锌轴配反应的光谱及热力学研究

A STUDY OF THERMODYNAMICS AND SPECTRA IN AXIAL COORDINATIONS OF SYMMETRICAL AND UNSYMMETRICAL DERIVATIVES OF TETRAPHENYLPORPHINATOZINC (Ⅱ)

合成非对称对位取代５－（４－乙酰胺基苯基）－１０，１５，２０－三（４－甲基苯基）卟啉锌。考察了Ｚｎ（ｐ－Ｘ）ＴＰＰ（Ｘ＝Ｃｌ，Ｈ，ＣＨ３，ＯＣＨ３）及非对称Ｚｎ（ｐ－ＮＨＣＯＣＨ３）（ｐ－ＣＨ３）３ＴＰＰ与咪唑类配体［Ｉｍ、２－ＭｅＩｍ、Ｎ－ＭｅＩｍ、ＧＭＺ、ＮｉＩｍ（ｐ－Ｃｌ）］轴配反应的电子吸收光谱。阐述了诸因素对谱带红移和Ａβ／Ａα值降低的影响。用紫外－可见光谱和Ｒｏｓｅ－Ｄｒａｇｅ数据处理方法，测量了轴配反应的配位数和平衡常数。利用温度系数法测量了体系的ΔｒＨｍＯ和ΔｒＳｍＯ。发现对称及非对称卟啉锌与各配体轴配反应的ｌｏｇＫＯ与卟啉环上的取代基的Ｈａｍｍｅｔ参数之间存在线性自由能关系。

5 (4 acetamidophenyl) 10,15,20 tris(4 mthylphenyl) porphinatozinc (Ⅱ) was synthesized. The electric absorption spectra of axial coordination reaction of symmetrical and unsymmetrical Zn( p X)TPP with imedaxole series were investigated. The influence on a red shift of entire spectra and a decrease in A β/ A α was discussed. Coordination number and equilibrium constants of axial coordination reaction were measured by visible spectra techniques and the method of Rose Drage. The changes of standard molar enthapy Δ r H m O and standard molar Δ r S m O of reactions were obtained from the plots of ln K O vs 1/ T . It was found that log K eq O for imedazole series addition varies linearly with the sum of the Hammett sigma constants for all complexes investigated.