A series of Ni2+ complexes of N-(7-hydroxy-4-methyl-8-coumarinyl)-glycine (H2mugly) and N-(7-hydroxy-4-methyl-8-coumarinyl)-L-alanine (H2muala) has been prepared by self-assembly of Ni(CH3COO)2·4H2O with ligands in the presence of alkali metal ions. The complexes have been characterized by elemental analysis, thermogravimetry, IR and ESI-MS studies, and several of these complexes have also been structurally characterized by X-ray crystallography. Interestingly, the alkali metal ions have been found to direct the self-assembly processes and facilitate the formation of oligonuclear structures. Structural investigations showed that the molecular clusters displayed intriguing architectures including heptanickel metallocrowns with highly symmetrical hexagonal shapes, a heterobimetallic molecular cage and a pentanickel cluster with a nanobasket shape. The diversity of the coordination geometries and the cluster structures are discussed in detail.
在碱
金属离子存在下,通过 Ni(CH3COO)2-4H2O 与
配体的自组装,制备了一系列 N-(7-羟基-4-甲基-8-
香豆素基)-甘
氨酸(H2mugly)和 N-(7-羟基-4-甲基-8-
香豆素基)-
L-丙氨酸(H2muala)的 Ni2+ 复合物。这些配合物通过元素分析、热重、红外和 ESI-MS 研究进行了表征,其中一些配合物还通过 X 射线晶体学进行了结构表征。有趣的是,研究发现碱
金属离子能引导自组装过程并促进寡核结构的形成。结构研究表明,这些分子簇呈现出奇妙的结构,包括具有高度对称六边形的庚
镍金属冠、杂双
金属分子笼和具有纳米篮形状的戊
镍簇。本文详细讨论了配位几何和簇结构的多样性。