College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, PR China.
Dalton Trans. 2010 Sep 21;39(35):8210-8. doi: 10.1039/c002581j. Epub 2010 Aug 5.
Six transition metal coordination polymers, [Cu(3)(nbta)(2)(bipy)(2)(H(2)O)(2)] x 2 H(2)O (1), [Cu(3)(nbta)(2)(bpp)(2)(H(2)O)(2)] x 2 H(2)O (2), [Co(3)(nbta)(2)(bipy)(3)(H(2)O)(2)] x 2 H(2)O (3), [Co(3)(nbta)(2)(bpp)(2)(H(2)O)(2)] (4), [Ni(2)(Hnbta)(2)(bipy)(2)(H(2)O)(2)] (5) and [Ni(3)(nbta)(2)(bpa)(3)(H(2)O)(2)] x 2 H(2)O (6) (H(3)nbta = 5-nitro-1,2,3-benzenetricarboxylic acid, bipy = 4,4'-bipyridine, bpa = 1,2-bis(4-pyridyl)ethane, bpp = 1,3-bis(4-pyridyl)propane), have been hydrothermally synthesized by the reactions of Cu(II), Co(II) and Ni(II) salts with H(3)nbta in the presence of dipyridyl-type co-ligands, respectively. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and TG analyses. Compounds 1-4 and 6 exhibit 3D pillared-layer structures while compound 5 has a 2D layer. The nbta(3-) ligands in the 2D carboxylate layer motifs of 1-4 and 6 connect transition metal ions in different coordination modes, and the dipyridyl-type co-ligands in compounds 1-4 and 6 serve as the pillar between the 2D layers, creating 3D open frameworks. From a topologic point of view, complex 1, 2 and 4 present 4-connected 3D coordination frameworks with the topologies of (4(2) x 6(2) x 8(2)) (6(2) x 7(2) x 8(2)) (4(2) x 6(2) x 7 x 8), (6(4) x 8(2)) (4(2) x 6(4)) (4(2) x 6(4)) and (4 x 6(4) x 8)(4(4) x 6(2))(4(3) x 6(3)) respectively. Complex 3 shows a (4,5)-connected 3D network with (4(2) x 6(7) x 8)(6(4) x 8(2))(4(2) x 6(4)) topology. Whereas the structure of 5 is a 2D (4,4) net due to the partially deprotonated H(3)nbta ligand existed. Complex 6 features a 3D (4,5)-connected framework with (4 x 6(8) x 8) (6(5) x 8) (4 x 6(5)) topology, also exhibiting the intriguing helical motif. The variable-temperature magnetic susceptibility studies reveal antiferromagnetic interactions between Cu(II) or Co(II) ions in 1, 2, 3, 4 and ferromagnetic interactions between Ni(II) ions for 5 and 6, respectively.
六种过渡金属配位聚合物，[Cu(3)(nbta)(2)(bipy)(2)(H(2)O)(2)] x 2 H(2)O (1)、[Cu(3)(nbta)(2)(bpp)(2)(H(2)O)(2)] x 2 H(2)O (2)、[Co(3)(nbta)(2)(bipy)(3)(H(2)O)(2)] x 2 H(2)O (3)、[Co(3)(nbta)(2)(bpp)(2)(H(2)O)(2)] (4)、[Ni(2)(Hnbta)(2)(bipy)(2)(H(2)O)(2)] (5) 和 [Ni(3)(nbta)(2)(bpa)(3)(H(2)O)(2)] x 2 H(2)O (6) (H(3)nbta = 5-硝基-1,2,3-苯三甲酸，bipy = 4,4'-联吡啶，bpa = 1,2-双(4-吡啶基)乙烷，bpp = 1,3-双(4-吡啶基)丙烷)，分别通过 Cu(II)、Co(II)和 Ni(II)盐与 H(3)nbta 在二吡啶型共配体存在下的反应水热合成。它们的结构通过单晶 X 射线衍射分析确定，并通过元素分析、红外光谱和热重分析进一步表征。化合物 1-4 和 6 表现出 3D 支柱层结构，而化合物 5 具有 2D 层。nbta(3-)配体在 1-4 和 6 的 2D 羧酸层图案中以不同的配位模式连接过渡金属离子，并且二吡啶型共配体在化合物 1-4 和 6 中充当 2D 层之间的支柱，形成 3D 开放框架。从拓扑学的角度来看，配合物 1、2 和 4 呈现出具有拓扑结构的 4-连接 3D 配位骨架(4(2) x 6(2) x 8(2)) (6(2) x 7(2) x 8(2)) (4(2) x 6(2) x 7 x 8)、(6(4) x 8(2)) (4(2) x 6(4)) (4(2) x 6(4))和(4 x 6(4) x 8)(4(4) x 6(2))(4(3) x 6(3))，而 3 显示出(4,5)-连接的 3D 网络，具有(4(2) x 6(7) x 8)(6(4) x 8(2))(4(2) x 6(4))拓扑结构。而 5 的结构是由于部分去质子化的 H(3)nbta 配体的存在，是一个 2D(4,4)网。配合物 6 具有 3D(4,5)-连接的框架，具有(4 x 6(8) x 8) (6(5) x 8) (4 x 6(5))拓扑结构，也表现出有趣的螺旋图案。变温磁化率研究表明，1、2、3、4 中 Cu(II)或 Co(II)离子之间存在反铁磁相互作用，5 和 6 中 Ni(II)离子之间存在铁磁相互作用。
