Kinetic and equilibrium studies of the acid dissociation of the cobalt(II) complexes of <i>N,N'</i>-dialkyl- 1,10-phenanthroline-2,9-dimathanamine ligands
作者:Hongwei Sun、Zhifen Zhou、Huakuan Lin、Guanghua Zhao、Shourong Zhu、Xuncheng Su、Yunti Chen
DOI:10.1139/v99-160
日期:1999.9.1
The complexation property and the acid dissociation kinetics of four N,N'-dialkyl-1,10-phenanthroline-2,9-dimathanamine complexes with cobalt(II) were studied using a pH meter and a stopped-flow spectrophotometer. In 6.6 × 10-3~0.5 mol dm-3 HCl (I = 0.5 mol dm-3 HCl + NaCl), the dissociation rate follows the law kobs = kK2[H+]/(1 + K2[H+]). The acid dissociation can be rationalized in terms of a four-step
使用 pH 计和停流分光光度计研究了四种 N,N'-二烷基-1,10-菲咯啉-2,9-二马胺与钴 (II) 的络合性质和酸解动力学。在 6.6 × 10-3~0.5 mol dm-3 HCl(I = 0.5 mol dm-3 HCl + NaCl)中,解离速率遵循 kobs = kK2[H+]/(1 + K2[H+]) 定律。酸解离可以根据四步动力学过程进行合理化,包括两个快速的预平衡质子化和 Co(II)-N(菲咯啉)键的限速裂解。确定速率的温度依赖性,并获得适当的热力学参数。ΔH 不等于和 ΔS 不等于之间的线性关系表明存在等速温度 Tiso 为 282 ± 2 K。关键词: N,N'-二烷基-1,10-菲咯啉-2,9-二马胺,