A novel two-dimensional framework based on unprecedented cadmium(II) chains

Abstract

The bent ligand 4-[(1H-1,2,4-triazol-1-yl)methyl]benzoic acid (HL) has been used to create the novel two-dimensional coordination polymer poly[mu(2)-aqua-mu(2)-chlorido-{mu(2)-4-[(1H-1,2,4-triazol-1-yl)methyl]benzoato}cadmium(II)], [Cd(C(10)H(8)N(3)O(2))Cl(H(2)O)](n), under hydrothermal reaction of HL with cadmium chloride. The crystallographically unique Cd atom is seven-coordinated in an approximately pentagonal-bipyramidal environment of two carboxylate O atoms, two water O atoms, two Cl atoms and one triazole N atom. A notable feature is the presence of zigzag ...Cd...Cd... inorganic chains, in which neighboring Cd(II) ions are doubly bridged by pairs of mu(2)-Cl atoms and mu(2)-H(2)O ligands in an alternating fashion. To the authors' knowledge, this is the first example containing this bridging mode in a cadmium(II) framework. The chains are connected to one another through the bridging L(-) ligand into a two-dimensional undulating network. All of the two-dimensional nets stack exactly together in an ...AA... stacking sequence along the crystallographic b axis. Neighboring layers are further linked into a three-dimensional framework via interlayer hydrogen-bonding interactions.

Poly[[{μ4-3-[(1H-1,2,4-triazol-1-yl)methyl]benzoato}zinc(II)] hemihydrate]: a novel two-dimensional framework formed by self-association of zinc(II) sulfate with 3-[(1H-1,2,4-triazol-1-yl)methyl]benzoic acid

“…The water molecules do not appear to interact strongly with the framework. The cavities in this structure are smaller than similar cavities composed of two Cd II centres and two similar bent 4-[(1H-1,2,4-triazol-1-yl)methyl]benzoate ligands, in which the CdÁ Á ÁCd separation is 12.40 (4) Å (Qin et al, 2009). The smaller cavity size in (I) may be caused by the 3-substituted ligand being shorter than the 4-substituted ligand in terms of the distance from the carboxylate O atoms to the triazole N atom.…”

“…Supramolecular complexes based on bent unsymmetric ligands containing 1,2,4-triazole and carboxylic acid groups have been less extensively studied (Ding et al, 2008), so these bent unsymmetric ligands offer great potential for creating novel frameworks. Previously, we have reported the M II (M = Co, Cd and Zn) coordination chemistry of the carboxylate-substituted 1,2,4-triazole 4-[(1H-1,2,4-triazol-1yl)methyl]benzoic acid (Zhao et al, 2007;Qin et al, 2009). In the present work, the new isomeric bent organic ligand 3-[(1H-1,2,4-triazol-1-yl)methyl]benzoic acid (HL) was employed in a self-assembly reaction with zinc sulfate under hydrothermal conditions to create the title novel supra-…”

Supramolecular Coordination Assemblies Constructed From Multifunctional Azole-Containing Carboxylic Acids

“…NETXIU and NOFGAR use the title ligands as 3-connected nodes and metal atoms with terminal water as linkers. BOKXUV[130]FIBJEG[133]TIVZOO[132]WOFVET[94]NOFGAR[136]FENSUN[131]KEKWIH[134]TIVZUU[132]VIQZAX[98]NOFGEV[136]FENSUN03[132]TIVZII[132]TIWBAD[132]NETXIU[135]EHAGAW[137]…”

catena-Poly[zinc(II)-bis[μ-2-(2,4-dichlorophenoxy)acetato]]

“…For metal-organic coordination polymers, see: Qin et al (2009); Huang et al (2008); Reineke et al (1999); Xiong et al (2002).…”