Effect of an alkyl chain substituent on the kinetics and thermodynamics of complexation of 8-hydroxyquinolines with Ni2+ and Co2+ in methanolic solutions
作者:M. Boumezioud、C. Tondre、P. Lagrange
DOI:10.1016/s0277-5387(00)86326-3
日期:——
thermodynamic as well as the kinetic parameters for the complexation of this ligand molecule with( Ni2+ and Co2+are compared with that of 8-hydroxyquinoline (HQ) in identical conditions (methanolic solutions with up to 0.4% of water, 0.1 M NaClO4, 0.1 M triethanolamine buffer). From stopped-flow experiments, the alkyl-chain substituent is shown to be responsible for a seven-fold decrease of the rate constant
7-(4-乙基-1-甲基辛基)-8-羟基喹啉(C 11 HQ)是工业萃取Kelex 100的活性组分的热力学以及用于与这种配位体分子的络合的动力学参数(镍2+和Co 2+与在相同条件下(高达水0.4%,0.1M的NaClO甲醇溶液8-羟基喹啉(HQ)的比较4,0.1M三乙醇胺缓冲液),从停流实验中,烷基链取代基表明配体中性形式与Ni 2+离子之间1:1配合物形成的速率常数降低了七倍,Co 2+的行为相似离子,仅使用烷基化的配体可获得定量数据。考虑了两种不同的机理来解释观察到的速率常数的pH依赖性,该速率常数归因于金属水解而不是配体去质子化。