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Two new three-dimensional metal–organic frameworks, [H2N(CH3)2]2[Zn(btec)]·DMF (1, H4btec=1,2,4,5-benzenetetracarboxylate acid) and [H2N(CH3)2][ZnLi(btec)]·DMF (2), have been solvothermally synthesized and structurally characterized by single crystal X-ray diffraction. Compound 1 based on μ4-btec features an anionic homometallic framework with 4-connected pts topology. Compound 2 is a heterometallic organic framework with rare (4, 4, 8)-connected network topology, which can be considered as constitute of a Li-btec (pts) net and a Zn-btec net. Moreover, the luminescent properties of two compounds are investigated in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: Four homochiral metal camphorates with auxiliary bipyridine ligands are hydrothermally synthesized and structurally characterized. The structure of compound [Cd(d-Hcam)2(bpa)(H2O)] n (1; d-H2cam= d-(+)-camphoric acid, bpa=1,2-bis(4-pyridyl)-ethane) presents a rare case where the d-Hcam is not a bridging ligand, but a dangling unit attached to the infinite [Cd(bpa)] chain. Compounds [M2(d-cam)2(4,4′-bipy)(H2O)4] n (M=Co, 2; M=Cd, 3; 4,4′-bipy=4,4′-bipyridine) are isostructural and have homochiral [M(d-cam)] n chains linked by the 4,4′-bipy ligands into a honeycomb-like 63 layer. Compound [Zn2(d-cam)2(PPE)2] n (4, PPE=1-(4-pyridyl)-2-(2-pyridyl)-ethylene) consists of the grid-like 44 layers with the dinuclear Zn2(COO)4 units and d-cam ligands, where the PPE ligands are only monodentately coordinated to the dinuclear units and act as the separators between two homochiral layers. The results demonstrate the rich coordination chemistry of the enantiopure d-camphorate ligand and the structural diversity of metal–camphorate compounds. [Copyright &y& Elsevier]

The hydrothermal reaction of an aqueous solution of Cu(CH3COO)2.H2O, 1,2,4,5-benzenetetracarboxylic acid and 4,4'-bipyridine gave rise to the interesting title three-dimensional polymer {[Cu6(btec)3(4,4'-bpy)3(H2O)n(btec is 1,2,4,5-benzenetetracarboxylate, C10H2O84-, and 4,4'-bpy is 4,4'-bipyridine, C10H8N2), in which each btec ligand links six copper(II) cations into a lamellar [Cu6(btec)3(H2O)2]n subpolymer framework. There are two distinct diamine units and two distinct carboxylate units, with one of each lying across an inversion centre. [ABSTRACT FROM AUTHOR]

In the title compound, [Zn2(SO3)2(C10H8N2)2], Zn2+ and SO32− form a dinuclear unit, with an inversion center at the mid-point of the Zn...Zn vector. Each Zn atom has distorted octahedral geometry and is coordinated by four O atoms from two SO32− anions and two N atoms of the 2,2′-bipyridine ligand. [ABSTRACT FROM AUTHOR]

The title complex, [Zn(C8H6NO2)2(H2O)4], consists of a central zinc(II) atom coordinated by two trans 3-(4-pyridyl)­acrylate ligands via their N atoms and by four water ligands. The Zn atom is located on a centre of inversion. Extensive inter-complex hydrogen bonding occurs between the water ligands and the carboxyl­ate groups, resulting in a three-dimensional network. [ABSTRACT FROM AUTHOR]

A novel layered MOF, {[Pb(HBic)(HBic)Cl] · 2HO} ( I), was hydrothermally obtained by the reaction of PbCl with 1- H-benzimidazole-5-carboxylic acid (HBic) and fully characterized by single-crystal X-ray diffraction, elemental analysis, FT-IR, TG-DTA, and luminescent spectra. Structural analysis suggests that complex I is a 2D layer assembled from helical Pb(II)-HBicchains and bridging chloride linkers, which is H-bonded together into a 3D supramolecular network. Additionally, I in the solid-state exhibits a favorable fluorescent emission at room temperature due to the intraligand charge transfer, suggesting its potential application as fluorescence materials. [ABSTRACT FROM AUTHOR]

Two novel lead(II) coordination polymers with the same mixed ligands, [Pb(AAP)(NIP)] ( I) and {[Pb(AAP)(NIP)] · 2HO} ( II) (AAP = 4-aminoantipyrine and NIP = 5-nitroisophthalate), were prepared by controlling the pH value of the reaction mixture. Complexes I and II were characterized by X-ray single-crystal diffraction analyses (CIF files CCDC nos. 936101 ( I) and 936102 ( II)). Complex I with terminal AAP molecule displays a linear chain with hemidirected Pb ions connected by bis-bidentate chelating-NIP anions. By contrast, complex II exhibits a dimeric {Pb(AAP)}-based coplanar layer extended by bidentate chelating-bidentate chelating and bridging-NIP anions. Obviously, the pH-directed structural difference is dominated by the competitive binding modes of the AAP and carboxylate groups of NIP ligands. Both complexes display different thermal stability due to structural difference and similar emissions originated from the intra- and/or inter-ligand electron transfer, suggesting their potential application as luminescent materials. [ABSTRACT FROM AUTHOR]

In the title complex, [CdBr2(C10H8N2)2], a crystallographic twofold rotation axis passes through the CdII ion, which is six-coordinated by four N atoms of two symmetry-related 2,2′-bipyridine ligands and two symmetry-related Br− anions. [ABSTRACT FROM AUTHOR]