Syntheses, Crystal Structures, Luminescent Properties, and Electrochemical Synthesis of Group 12 Element Coordination Polymers with 4-Substituted 1,2,4-Triazole Ligands

The self-assembly of Zn(II), Cd(II), or Hg(II) salts with long flexible 1,2,4-triazole-based ligands resulted in coordination polymers and mononuclear complexes of diverse topology. Indeed, the 1D chain [ZnCl2(btpm)] (1) (P (1) over bar), the 2D square grid [Zn(btpm)(2) (H2O)](BF4)(2) center dot 2btpm.8H(2)O (2) (P2(1)2(1)2), and the 1D chain [Cd3Cl6(btpm)(2)]center dot 8H(2)O(3) (P (1) over bar) with btpm = bis(4-(1,2,4-triazol-4-yl)phenyl)methane were crystallized. In addition, the mononuclear complexes [ZnCl2(ppt)(2)] (4) (I2) and [HgBr2(ppt)(2)] (5) (C2) were obtained along with the 1D polymer [Cd2Cl2(PPt)(4)](CdCl4)center dot 4DMF (6) (P1) with ppt = (4-phenoxyphenyl)-1,2,4-triazole. 1D chains of the formula [ZnCl2(tpca)] ( 7 ) (P2(1)/c) and [HgBr2(tpca)] (8) (P2(1)/c) along with the 2D net [Cd(tpca)(2)(H2O)(2)]center dot 2H(2)O (C2/c) (9) with tpca = N-(1,2,4-triazol-4-yl)pyridine-3-carboxamide were obtained. In addition, the X-ray structures of tpca and ppt are described. All compounds display solid-state blue luminescence, which has been investigated in detail. Electrochemical synthesis of 2, which has been rarely applied for MOF synthesis, revealed hollow particles.