金属离子与卟啉的嵌入反应动力学研究(Ⅷ)meso-四对羟基苯卟啉与铜(Ⅱ)在DMF中的配位反应

Kinetics Study on the Incorporating Metal Ion into Porphyrin(Ⅷ)—Formation reaction of Cu(Ⅱ)and meso-tetra-p-hydroxylphenyl porphyrin compound in Dimethylfermamide

在 35.0± 0 .1℃、离子强度 0 .1(0 .1mol·L- 1NaClO4 )条件下 ,研究了在N ,N’ 二甲基甲酰胺溶液中meso 四对羟基苯卟啉与Cu 的配位反应动力学。根据在此体系中CuCl2 的缔合状态 ,溶液氢离子浓度对反应速率的影响 ,得到铜 卟啉生成反应的动力学方程 ,测量了该反应的活化参量。结果表明反应遵循缔合 离解机理 。

Kinetics of the coordination reaction of meso tetra p hydroxylphenyl porphyrin(abbr. TP OHTPP) with Cu? in dimethylformamide(DMF) has been studied under 35.0±0.1℃ and with ion strengh 0.1(NaClO 4). The kinetic equation of the formation reaction of the metalloporphyrin has been obtained as d[Cu?P]/d t = k [CuCl +][P] T /(1.0+[H +]/ K a 3 +[H +] 2/ K a3 K a4 ), k =0.4671 L 2·mol -2 ·s -1 , K a3 =2.226×10 -3 , K a4 = 3.691×10 -4 , accorting to the associated states of CuCl 2 in DMF and the dependence of reaction rate on both [Cu?Cl +] and [H +]. The active parameters of the reaction have been investigated as E a = 81.86 kJ·mol -1 ·K -1 , ΔH ≠= 80.39 kJ·mol -1 , ΔG ≠= 64.20 kJ·mol -1 and ΔS ≠= 52.55J·mol -1 ·K -1 . The results of the study shows that the reaction follows the mechanism of association dissociation with its rate limit step of the dissociation of the activeted complex[CuCl+…H 2P]. $$$$