摘要
本文用电位—PH 法测得了5,5,7,12,12,14—六甲基一四氮杂环十叫烷 L^1及其 N-乙酸取代物 L^2和 L^3的加质子常数。发现在大环氮原子α位引入烷基或在氮上引入乙羧基会使配体碱性增强。在水溶液中它们主要似 H_2L 的形式存在。探讨了它们与金属 N^(2+)的配合速率结果表明它们的配合速率有如下关系:L^1》L^2>L^3.
The protonation constants of 5,5,7,12,12,14—hexamethyltetraaza-cyclote- tradecane(L^1)and N—siubsttuted derivations L^2,L^3 were determined by potentiometric titration.It is found that the basicity of these ligands is increased when methyl was introduced to the alpha-carbon of the N—atom or acetic acid to N—atomin L^1.In aqueous solutions of the macrocycles, the main species present is theudiprotonation form H2L.the kinetcs of complex formation between L^1,L^2,L^3and Ni(Ⅰ)have been studied.The complexation rate was obtained as follows:L^1>>L^2>L^3.
出处
《安徽大学学报（自然科学版）》
CAS
1991年第4期72-76,共5页
Journal of Anhui University(Natural Science Edition)
关键词
氮杂大环
配位化学
加质子常数
hexamethyltetraazacyclotetradecame derivations
protonation constants
