A Variety of 1D to 3D Metal−Organic Coordination Architectures Assembled with 1,1′-(2,2′-Oxybis(ethane-2,1-diyl))bis(1H-imidazole)

A new long flexible ligand, L = 1,1′-(2,2′-oxybis(ethane-2,1-diyl))bis(1H-imidazole), has been prepared. The hydrothermal reactions of L with various metal ions (M(II) = Co, Zn, and Cd) as well as a series of aromatic polycarboxylate co-ligands yielded seven new metal−organic frameworks consisting of 1D, 2D, and 3D structures. Complexes 1–5 are constructed by SBU I (a M2L2 metallocycle), while complexes 6 and 7 are assembled by SBU II (left- and right-handed helical [M(L)]n chains). In 1and 2, the SBUs I are bridged by 1,2-BDC (1,2-benzenedicarboxylate) and 3,5-DNP (3,5-dinitrophthalate) anions with the same coordination modes to generate 1D chains with repeated rings. 3 exhibits a typically 3-fold interpenetrated 3-connected (10,3)-b net. In 4, the Co centers are connected by μ3-OH and carboxylic O atoms to form a cobalt−oxygen tetranuclear cluster. 5 represents an uncommon example of a 3,4-connected net with (83)2(85 × 10) topology. In 6, the SBUs II are extended by 1,4-BDC (1,4-benzenedicarboxylate) anions to afford highly undulated 2D (4, 4) layers. In 7, the [Cd3(1,3-BDC)3] ladders connect to SBUs II to form a corrugated 2D network. A comparison of all complexes demonstrates that the structural characteristics of L ligand and organic counteranions simultaneously play an important role in the construction of the complexes. In addition, complexes 3 and 7 exhibit strong blue photoluminescence, and compound 4 is an antiferromagnet.

一种新型长而柔韧的配体L = 1,1′-(2,2′-氧双(乙烷-2,1-二亚乙基))双(1H-咪唑)，已成功合成。配体L与多种金属离子（M(II) = Co, Zn, 和 Cd）以及一系列芳香族多羧酸共配体进行水热反应，产生了由一维、二维和三维结构组成的七种新型金属-有机框架。复合物1至5通过SBU I（一个M2L2金属环）构建，而复合物6和7则通过SBU II（左旋和右旋螺旋[M(L)]n链）组装。在1和2中，SBU I被具有相同配位方式的1,2-BDC（1,2-苯二羧酸）和3,5-DNP（3,5-二硝基苯甲酸）阴离子桥接，生成具有重复环的一维链。3呈现出典型的三重穿插的三连接（10,3）-b网状结构。在4中，钴中心通过μ3-OH和羧酸O原子相连，形成一个钴-氧四核簇。5代表了一种不常见的3,4连接网络，具有(83)2(85 × 10)拓扑结构。在6中，SBU II被1,4-BDC（1,4-苯二羧酸）阴离子扩展，形成高度波动的二维（4,4）层。在7中，[Cd3(1,3-BDC)3]梯状结构连接到SBU II，形成一个波纹状的二维网络。对所有复合物的比较表明，L配体和有机反离子在复合物的构建中同时发挥着至关重要的作用。此外，复合物3和7显示出强烈的蓝色光致发光，而化合物4则是一种反铁磁性物质。