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The reaction of the dithioether ligand, 2,3-bis(5-methyl-1,3,4-thiadiazole-2-thiomethyl) quinoxaline ( L) with AgBF4, leads to the formation of a novel complex {[Ag L](BF4)}∞ 1, which has been characterized by single-crystal X-ray diffraction analysis: monoclinic, space group C2/ c, with a = 20.316(7) Å, b = 12.401(4) Å, c = 18.039(6) Å, β = 108.404(6)° and V = 4312(3) Å3. The crystal structure of the complex consists of 1D {[Ag L]+}∞ cation chain and BF4 − anions. In 1, the coordination geometry of AgI center can be best described as trigonal planar coordinated by three N from two distinct L ligands. The ligand is polydentate with one end adopting a bidentate conformation to chelate an AgI resulting in an infinite chain along b axis. There exist Ag⋯N weak coordination, π–π stacking and F⋯S weak interactions in the complex, and these weak interactions link the 1D complex into 3D supramolecular structure and further stabilize the crystal structure in the solid state. [ABSTRACT FROM AUTHOR]I resulting in an infinite chain along b axis. There exist Ag⋯N weak coordination, π–π stacking and F⋯S weak interactions in the complex, and these weak interactions link the 1D complex into 3D supramolecular structure and further stabilize the crystal structure in the solid state. [ABSTRACT FROM AUTHOR]

The crystal structure of a one-dimensional ladder-shape complex [CoL(H2O)]·2H2O, (L being 1,5-diazacyclooctane- N, N′-diacetate acid), has been determined by X-ray diffraction analysis: monoclinic, space group P21/c with a = 14.406(4) Å, b = 7.380(2) Å, c = 14.594(5) Å, β = 112.685(2)°, M r = 341.23, V = 1431.5(8) Å3, Z = 4. The CoII center is penta-coordinated by two O atoms of the carboxylic pendant arms, two nitrogen donors of the 1,5-diazacyclooctane (DACO) moiety, and a water molecule. The coordination geometry of CoII could be described as a distorted square pyramid and the DACO backbone adopts a normal boat/chair conformation. The complex forms a one-dimensional ladder-shape structure through inter- and intra-molecular O—H···O hydrogen bonds. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) network complex [Cd( L)2(NCS)2(H2O)2], L being 2,5-bis(4-pyridyl)-1,3,4-oxadiazole, has been synthesized and structurally determined by X-ray diffraction analysis: triclinic, space group P-1 with a = 7.8863(9) Å, b = 8.6287(10) Å, c = 11.4696(12) Å, α = 94.346(2)°, β = 109.331(2)°, γ = 94.354(2)°, Mr = 713.04, V = 730.13(14) Å3, Z = 1. The crystal structure of the title complex reveals that it is a neutral molecule and the Cd(II) ion is at the center of symmetry. Each Cd(II) is six-coordinated and the CdN4O2 coordination sphere can be considered as an octahedron. The most striking feature of this complex resides in the formation of a 3D network through hydrogen bonds and π-π stacking interactions. [ABSTRACT FROM AUTHOR]

The diprotonated perchlorate salt of a new 1,5-diazacyclooctane (DACO) mesocycle functionalized by two imidazole pendants, N,N′-bis(1-methylimidazole-2-methyl)-1,5-diazacyclo-octane (C16H28N6Cl2O8), has been synthesized and the structure determined by X-ray diffraction analysis. The title compound crystallizes in the monoclinic system, space group P21/ c with a = 11.964(2), b = 13.251(3), c = 14.741(3) Å, β = 106.00(3)°, Mr = 503.34, V = 2246(1) Å3, Z = 4. The crystal structure of the title compound reveals that the DACO ring is also folded up into the “chair/boat” configuration, which is consistent with the configuration in most of the transition metal complexes of DACO and its derivatives. The two imidazole pendants of the compound are in cis position with a dihedral angle of 16.0(4)°. [ABSTRACT FROM AUTHOR]