College of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, Henan, P. R. China.
Dalton Trans. 2013 Oct 21;42(39):14268-80. doi: 10.1039/c3dt51486b.
2-Carboxylphenyl, 3-carboxylphenyl and 4-carboxylphenyl groups were introduced into the 2-position of imidazole-4,5-dicarboxylate system, respectively, obtaining three multi-functional ligands 2-(2-carboxylphenyl)-1H-imidazole-4,5-dicarboxylic acid (o-CPhH4IDC), 2-(3-carboxylphenyl)-1H-imidazole-4,5-dicarboxylic acid (m-CPhH4IDC) and 2-(4-carboxylphenyl)-1H-imidazole-4,5-dicarboxylic acid (p-CPhH4IDC). Then the three organic ligands are employed to react with Sr(II) and Cd(II) ions. Subsequently, five 3D or 2D polymers, [Sr(o-CPhH2IDC)]n (1), [Sr3(m-CPhHIDC)2(H2O)3]n (2), [Sr(p-CPhH2IDC)(H2O)]n (3), [Cd(o-CPhH2IDC)(H2O)2]n (4) and {[Cd3(m-CPhHIDC)2(H2O)8]·2H2O}n (5), have been hydro(solvo)thermally synthesized and structurally characterized. Compound 1 is a (5,5)-connected 3D structure with unique “H-shape” channels. Three kinds of coordination environments around the Sr atoms are exhibited in compound 2. Both compounds 1 and 2 contain unusual irregular cages. Compound 3 displays a (4,6)-connected 3D porous framework composed of right-handed helices connected by p-CPhH2IDC(2−) anions. Both compounds 4 and 5 present net-like layer structures. These various architectures demonstrate the versatile coordination abilities of the three imidazole-based multi-carboxylate ligands.
2-羧基苯基、3-羧基苯基和 4-羧基苯基分别被引入咪唑-4,5-二羧酸的 2-位，得到三个多功能配体 2-(2-羧基苯基)-1H-咪唑-4,5-二羧酸(o-CPhH4IDC)、2-(3-羧基苯基)-1H-咪唑-4,5-二羧酸(m-CPhH4IDC)和 2-(4-羧基苯基)-1H-咪唑-4,5-二羧酸(p-CPhH4IDC)。然后，这三个有机配体与 Sr(II)和 Cd(II)离子反应。随后，通过水热合成法得到了五个 3D 或 2D 聚合物，[Sr(o-CPhH2IDC)]n (1)、[Sr3(m-CPhHIDC)2(H2O)3]n (2)、[Sr(p-CPhH2IDC)(H2O)]n (3)、[Cd(o-CPhH2IDC)(H2O)2]n (4)和{[Cd3(m-CPhHIDC)2(H2O)8]·2H2O}n (5)，并对它们的结构进行了表征。化合物 1 是一个具有独特“H 形”通道的(5,5)-连接的 3D 结构。化合物 2 中展示了三种不同的 Sr 原子配位环境。化合物 1 和 2 都含有不规则的笼状结构。化合物 3 呈现出由右手螺旋通过 p-CPhH2IDC(2−)阴离子连接而成的(4,6)-连接的 3D 多孔骨架。化合物 4 和 5 则呈现出网状层状结构。这些不同的结构展示了三种基于咪唑的多羧酸配体的多功能配位能力。
