Syntheses, Structures, and Properties of Honeycomb and Square Grid Coordination Polymers with In Situ Formed 5-(2′-Pyrimidyl)tetrazolate

Solvothermal reactions of Zn(II), Cd(II), Mn(II), Co(II), or Ni(II) salts and 2-pyrimidinecarbonitrile (pymCN) in the presence of NaN3 in DMF yielded seven metal−organic coordination polymers formulated as [Zn(pymtz)2]n (1), [NaMII(pymtz)3]n·G (M = Zn 2, Cd 3, Mn 4, Co for 5, and Ni for 6; G = DMF and/or H2O) and [Cd(pymtz)2]n (7) [pymtz = 5-(2′-pyrimidyl)tetrazolato]. Compounds 2−6 are isomorphous and all contain neutral honeycomb layers in which pymtz serves as a bis(chelating) bridge between M(II) (M = Zn for 2, Cd for 3, Mn for 4, Co for 5, and Ni for 6) and Na+, and the ellipse stacking of the layers generates one-dimensional hexagonal channels. Compounds 1 and 7 exhibit different (4,4) square grid networks. In 1, the Zn ions are octahedrally coordinated and linked by pymtz ligands in the μ2 tridentate bridging mode, while in 7, the Cd(II) ions are eight-coordinated with a square prismatic geometry and bridged by bis(chelating) pymtz ligands. Compounds 2 and 3 can transform into 1 and 7, respectively, by immersing the sample in appropriate solvents. Interestingly, photoluminescence measurements on Zn(II) and Cd(II) compounds show that the emission bands can be correlated to the coordination modes of the pymtz ligands.

在二甲基亚砜（DMF）介质中，通过溶热反应将Zn(II)、Cd(II)、Mn(II)、Co(II)或Ni(II)盐与2-吡啶甲腈（pymCN）及NaN3共同作用，成功制备出七种金属-有机配位聚合物，其化学式分别为[Zn(pymtz)2]n（1）、[NaMII(pymtz)3]n·G（其中M = Zn（2）、Cd（3）、Mn（4）、Co（5）和Ni（6）；G = DMF及/或H2O）以及[Cd(pymtz)2]n（7），其中pymtz代表5-(2'-吡啶基)四唑ato。化合物2至6具有同质结构，均包含中性蜂窝状层，其中pymtz充当M(II)（M = Zn（2）、Cd（3）、Mn（4）、Co（5）和Ni（6））与Na+之间的双螯合桥连，层状椭圆堆积形成了二维六角通道。化合物1和7呈现出不同的（4,4）方形网格结构。在1中，Zn离子以八面体配位，通过pymtz配体以μ2三齿桥连模式相连接；而在7中，Cd(II)离子以八配位和方形棱柱几何结构存在，并由双螯合的pymtz配体桥连。化合物2和3可通过将样品浸入适当的溶剂中转变为1和7。有趣的是，对Zn(II)和Cd(II)化合物的光致发光测量表明，其发射带可以与pymtz配体的配位模式相关联。