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A novel 3D coordination polymer, ∞3[{Cu3(felden)}4(btec)3]·17H2O, has been assembled using cationic trigonal nodes, [CuII3(felden)]3+, generated by a tricompartmental ligand, H3felden, which results from the Schiff condensation reaction between 2,4,6-triformylphloroglucinol and N,N-dimethylethylenediamine. The tetraanion of the 1,2,4,5-benzenetetracaboxylic acid (H4btec) was employed as a spacer. The structure of 1 shows large icosahedral cavities and channels and the magnetic interaction between the copper(II) ions within the triangles is weak and antiferromagnetic. [ABSTRACT FROM AUTHOR]

Four new heterometallic 3d-4f complexes have been obtained using bi- and trinuclear building blocks: 1 ∞[Ni(L1)Gd(NO3)3(azbbpy)]·CH3CN (1), [Zn(L1)Eu(NO3)3(azbbpy)]·H2O (2), 1 ∞[(CuL2)2Gd(NO3)2(dca)] 3 and 1 ∞[(NiL2)2Dy(H2O)4(oxy-bbz)]NO3·3H2O (4), [H2L1 = 1,3-propanediyl-bis(2-iminomethylene-6-methoxyphenol), H2L2 = 2,6-di(acetoacetyl)pyridine, azbbpy = 1,3-bis(4-pyridyl)azulene, dca- = dicyanamide anion, and oxy-bbz = the dianion of the 4,4'-oxy-bis(benzoic) acid]. 1 and 2 represent the first complexes containing 1,3-bis(4-pyridyl)azulene as a ligand. 1, 3, and 4 are one-dimensional coordination polymers constructed from heterometallic nodes connected by the exo-dentate ligands. Helical chains are assembled in the case of 4. The analysis of the packing diagram for 1 reveals the occurrence of π-π stacking interactions established between the azulene rings from neighboring chains, which lead to supramolecular layers. The magnetic properties of 3 in the temperature range 1.9-300 K have been investigated. Intra-node ferromagnetic interactions are established between the CuII and GdIII ions (J = +2.7 cm-1, Ĥ = -J(ŜCu.ŜGd + ŜCu.ŜGd). [ABSTRACT FROM AUTHOR]

Abstract: Reaction of the copper precursor [Cu(MeOsaltn)(H2O)] (H2MeOsaltn= N,N′-bis(3-methoxysalicylidene)-1,3-diaminopropane) with Ln(NO3)3·6H2O (Ln=Sm and Tb) and pyrazine-2,3-dicarboxylic acid (H2pyrdic) results in the formation of 1D zigzag chains with the general formula of [Cu(MeOsaltn)Ln(NO3)(pyrdic)] n ·nDMF. X-ray crystal structures reveal that the samarium and terbium compounds are isostructural and crystalize in the orthorhombic space group Pbcn. The chains are composed of heterodinuclear copper–lanthanide building blocks which are linked by the pyrazine-2,3-dicarboxylate bridging units. Temperature-dependent susceptibility measurements indicate antiferromagnetic exchange interactions for the samarium–copper chain whereas for the terbium–copper compound ferromagnetic interactions are observed. [Copyright &y& Elsevier]