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A flexible bis(pyridylurea) ligand, 1,1′-[oxybis(2,1-phenylene)] bis(3-pyridin-3-ylurea) (L), has been synthesized and characterized. The interaction of L with ZnCl 2 and CdCl 2 has been investigated. In the structure of {[ZnLCl 2 ]·2DMF} n ( 1 ), the flexible ligands bridge the Zn II centers to form 1D helical chains with a pitch of 9.743 Å. The P and M helical chains are arranged equally, and the whole complex 1 is racemic. In the structure of [CdLCl 2 (DMF)] n ( 2 ), the flexible ligands bridge Cd II centers to form one-dimensional P and M helical chain structures in a similar manner. Then the chlorine atoms act as bridges in bidentate modes linking the P helical chain with M helical chain to form a 1D looped chain coordination polymer. [ABSTRACT FROM AUTHOR]

Highlights: [•] The helicity of one-dimensional chains is much dependent on the chirality of the building blocks. [•] The molecular building blocks may change the helicity of helical chain, but not affect the displayed Cotton effects. [•] Two different one-dimensional helical chains were obtained from the same reactions. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of 4,4′-di(3-pyridyl-4-pyrimidinyl) disulfide (3-PPDS) with AgNO3 leads to a unique 2D extended structure {[Ag(3-PPDS)(NO3)]} n (1) based on [Ag2(3-PPDS)2] macrocycle units, of which 1D inorganic [Ag(NO3)] n helical chains are generated. By contrast, definite Ag–S bonding interactions associated with the disulfide function have been established in {[Ag(2-PPDS)]ClO4} n (2), which is assembled of 4,4′-di(2-pyridyl-4-pyrimidinyl) disulfide (2-PPDS) with AgClO4. Solid state luminescent properties of complexes 1 and 2 are also examined. [Copyright &y& Elsevier]

Abstract: Two novel complexes [Cu(DBA)2(1,10-phen)] n (1) and [Cd(DBA)2(1,10-phen)2] (2) [HDBA=benzilic acid: (C6H5)2C(OH)COOH] have been synthesized and characterized by element analysis and fluorescence spectroscopy. The crystal structures of compounds 1, 2 and HDBA (3) were also determined. Complex 1 is a one-dimensional (1D) helical infinite chain, in which [(1,10)-phen]Cu(II) units were bridged by benzilic acid. Complex 2 is a mononuclear structure, and is self-assembled through π–π stacking interactions to form a 1D helical chain. Compound 3 is self-assembled to form a 1D helical chain through hydrogen bonds interactions. Thermal analyses indicate that complexes 1 and 2 are stable under 200 and 254°C in solid state, respectively. [Copyright &y& Elsevier]

Abstract: Three homochiral metal–organic coordination networks [Co2(l-Trp)2(Py)6]·Py·(ClO4)2 (1), [Ni(l-Trp)(Py)3]·H2O·ClO4 (2) and [Co2(l-Trp)(INT)2(H2O)2(ClO4)] (3), all containing natural amino acid l-HTrp (l-typtophan), were hydrothermally synthesized and structurally characterized. The compounds 1 and 2 crystallize in the orthorhombic space group C2221, with a =10.731(2)Å, b =19.709(4)Å, c =27.365(6)Å and Z =4 for 1 and a =10.710(10)Å, b =20.088(18)Å, c =27.63(3)Å and Z =8 for 2, respectively. The compound 3 has the monoclinic space group P21, with a =8.1934(14)Å, b =13.209(2)Å, c =12.464(2)Å, β =104.107(3)° and Z =2. Both 1 and 2 consist of 1D helical chains. Compound 3 is composed of 2D networks, which further assemble into a 3D supramolecular structure via weak interlayer interactions. The optically pure amino acid l-HTrp plays an important role leading to homochiral structures reported here. [Copyright &y& Elsevier]

Abstract: Six 2D and 3D supramolecular complexes [Cu(L1)(O2CCH3)2]·H2O (1), [Cu2(L2)2(μ2-O2CCH3)2](BF4)2 (2), [Cu2(L1)2(BDC)(NO3)2]·0.5H2O (3) [Cu2(L2)2(BDC)(NO3)2] (4), [Cu2(L3)2(BDC)(NO3)2]·0.5H2O (5) and [Cu2(L2)2(BDC)(H2O)2](BDC)·8H2O (6) (L1 =4′-(4-pyridyl)-2,2′:6′,2″-terpyridine, L2 =4′-(2-pyridyl)-2,2′:6′,2″-terpyridine, L3 =4′-phenyl-2,2′:6′,2″-terpyridine, BDC=1,4-benzenedicarboxylate), have been prepared and structurally characterized by X-ray diffraction crystallography. In complexes 1, 3, and 4, 1D channels are formed through C–H⋯O and C–H⋯N hydrogen-bonding interactions, and further linked into 3D structure via C–H⋯O and O–H⋯O interactions. Complex 2 is a 2D layer constructed from intermolecular C–H⋯F and π–π stacking interactions. In the structure of 6, the BDC2− ions and solvent water molecules form a novel 2D layer containing left- and right-handed helical chains via hydrogen-bonds, and an unusual discrete water octamer is formed within the layer. In 2, 4, 6 and [Ag2(L2)2](PF6)2 (7) the bonding types of pendent pyridines of L2 depending on the twist about central pyridines are involved in intramolecular (2 and 4), intermolecular (6) or coordination bonds (7) in-twist-order of 5.8°, 3.7°, 28.2° and 38.0°, respectively. Differently, the pendent pyridines of L1 in 1 and 3 form intermolecular hydrogen bonds despite of distinct corresponding twist angles of 25.1° (1) and 42.6°(3). Meanwhile, π–π stacking interactions are present in 1–6 and responsible for the stabilization of these complexes. [Copyright &y& Elsevier]

Abstract: A novel spring-like organotin complex [(Ph3Sn)(C7H5ClNO2)] n·3C6H6 (1), has been synthesized by treatment of 6-chloro-3-pyridineacetic acid bis(triphenyltin)oxide on the condition of reflux. The complex was characterized by elemental analysis, FT-IR, NMR (1H, 13C and 119Sn) spectroscopy, and X-ray crystallography diffraction analysis. The structure analyses reveals that complex 1 is an 1D infinite chain linked by intermolecular Sn–O bonds, in which the guest benzene molecules are established in the cavity of this helical chain; all the tin atoms of complex 1 are five-coordinated. [ABSTRACT FROM AUTHOR]