Copper(II) Complexes of Bis(1,4,7-triazacyclononane) Ligands with Polymethylene Bridging Groups: An Equilibrium and Structural Study
作者:Reem Haidar、Manus Ipek、Barnali DasGupta、Mohammed Yousaf、Leverett J. Zompa
DOI:10.1021/ic970070f
日期:1997.7.1
CuH(2)(EMn)(4+), and dicopper(II), Cu(2)(EMn)(4+), species. UV-vis spectroscopic continuous variation studies at pH 4.0 and 7.5 are interpreted on the basis of the principal equilibrium species obtained from the equilibrium models. Single-crystal X-ray diffraction studies on four complexes ([Cu(EM2)]SO(4).6H(2)O (1), [Cu(2)(EM2)Cl(4)].2H(2)O (2), [Cu(2)(EM6)Cl(4) ] (3), and [Cu(EM3)][ZnBr(4)].H(2)O (4)) characterize
描述了铜(II)通过一系列包含两个1,4,7-三氮杂环壬烷[9] aneN(3)的配体的络合,基团由长度为2至6个碳的多亚甲基链连接。使用pH电位法在水溶液中进行平衡建模研究表明,该系列的最小同源物EM2在稀水溶液中仅形成Cu(EM2)(2+)。该系列的所有其他配体形成稳定的1:1(质子化和非质子化)和2:1 dicopper(II)(羟基和非羟基)复合物。那些包含四个或更多个碳原子的桥链的配体可能在溶液中形成二聚体或低聚复合物。具有最短的聚亚甲基桥基的EM配体形成最稳定的1:1物种。在质子化的CuH(2)(EMn)(4+)的复杂稳定性中,配体之间的差异很小(n = 3-6),和dicopper(II),Cu(2)(EMn)(4+)物种。基于从平衡模型获得的主要平衡物质,解释了在pH 4.0和7.5下的紫外可见光谱连续变化研究。四种配合物([Cu(EM2)] SO(4).6H(2)O(1)