Positional isomerism of unsymmetrical semirigid ligands toward the construction of discrete and infinite coordination architectures of zinc(ii) and cadmium(ii) complexes
Structural diversity in polymeric and discrete complexes constructed by divalent transition metals and unsymmetrical quasi semirigid pyridinecarboxylate isomers
genuine supramolecular isomers have been successfully prepared from divalent transitionmetal ions (Mn(II), Co(II), Ni(II), Cu(II), and Zn(II)) and unsymmetrical quasi semirigid pyridinecarboxylate isomers, InMe-n-py (n = 2, 3, 4). Structural analyses reveal that the unsymmetrical quasi semirigid ligands manage the metal(II) ions to form discrete (0D) armed metallocycle and dinuclear paddlewheel molecule
已成功地从二价过渡金属离子(Mn(II),Co(II),Ni(II),Cu(II)和Zn(II))和不对称物质成功制备了包括两个真正的超分子异构体在内的九种聚合物和离散配合物准半刚性吡啶羧酸酯异构体,InMe- n -py (n = 2,3,4)。结构分析表明,不对称的准半刚性配体能控制金属离子形成离散的(0D)武装金属环和双核桨轮分子,1D色带,简单的2D菱形(4,4)网格,2D手性波浪方形(4,4 )网格,以及带有装饰(4,4)拓扑的2D双层边缘。发现非共价氢键和芳族堆积相互作用是辅助的二级相互作用,有助于金属(II)配合物的最终无机-有机杂化超分子网络的扩展和稳定。非对称准半刚性配体的位置异构和构象多样性以及二价金属离子的配位偏好在支配结构变异和网络复杂性方面起着关键作用。热失重的热重分析表明,这些配合物的骨架在高达约200℃的温度下都是热稳定的。220–400°C。可变温度,固态磁
Positional isomerism of unsymmetrical semirigid ligands toward the construction of discrete and infinite coordination architectures of zinc(ii) and cadmium(ii) complexes
作者:Jing-Yun Wu、Pin-Ting Yuan、Cheng-Chu Hsiao
DOI:10.1039/c3ce42398k
日期:——
Three unsymmetrical semirigid ligands, HInMe-n-py (n = 2, 3, 4), showing positional isomerism have assembled with ZnCl2 and CdCl2 to yield supramolecular coordination assemblies. Compound [Zn(InMe-2-py)2]·1/2THF·1/2CH3OH·1/4H2O (1) has a two-dimensional rhombus gridlike (4,4) layer structure constructed from the dinuclear paddlewheel [Zn2(O2C)4N2] units with two pendant side-arms. Compound [Zn2Cl2(InMe-3-py)2(HInMe-3-py)2] (2) forms a discrete armed M2L2 macrocycle, which connects with others by intermolecular O–H⋯O and C–H⋯Cl hydrogen bonds to give rise to a decorated three-dimensional supramolecular pcu net. Compound [Zn(InMe-4-py)2]·1/2H2O (3) adopts a two-dimensional chiral wavy (4,4) square grid. Opposite-handedness chiral wavy grids are stacked in an ABAB type of sequence that has small voids accommodating lattice water molecules. Compound [CdCl(InMe-3-py)] (4) displays a two-dimensional achiral meso layer in which the opposite-handedness Cd–L helical chains are interconnected by the Cd–O bridging bonds and stitched by zigzag Cd–Cl chains. Compound [Cd(InMe-4-py)2(H2O)2] (5) features a two-dimensional rhombus gridlike (4,4)-net. Through the connections of net-to-net O–H⋯O hydrogen bonds, the grids are offset-stacked to be a hydrogen-bonded three-dimensional oblique pcu net. The structural diversity and complexity in these supramolecular coordination architectures are most likely attributed to the various coordination modes adopted by these N- and O-donor ligands of different substituent position and the coordination preference exhibited by the metal ions. Thermogravimetric (TG) analyses showed that all the frameworks of compounds 1–5 exhibit a thermal stability higher than 300 °C. In addition, the solid-state photoluminescent properties of compounds 1–5 were investigated.