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Three new isostructural 3D lanthanide metal–organic frameworks (Ln‐MOFs), {H[LnL(H2O)]⋅2 H2O}n (1‐Ln) (Ln=Eu3+, Gd3+ and Tb3+), based on infinite lanthanide‐carboxylate chains were constructed by employing an ether‐separated 5,5′‐oxydiisophthalic acid (H4L) ligand under solvothermal reaction. 1‐Eu and 1‐Tb exhibit strong red and green emission, respectively, through the antenna effect, as demonstrated through a combination of calculation and experimental results. Moreover, a series of dichromatic doped 1‐EuxTby MOFs were fabricated by introducing different concentrations of Eu3+ and Tb3+ ions, and they display an unusual variation of luminescent colors from green, yellow, orange to red. 1‐Eu with channels decorated by ether O atoms and the open metal sites displays good performance for CO2 capture and conversion between CO2 and epoxides into cyclic carbonates. [ABSTRACT FROM AUTHOR]

Under solvothermalconditions, six new Zn(II) coordination polymers,[(CH3)2NH2]2[Zn(L)]·2H2O (1), [Zn2(L)(py)2] (2), [Zn2(L)(bpe)2]·bpe·6H2O (3), [Zn2(L)(bpe)(DMA)(H2O)]·5H2O (4), [Zn2(L)(bpy)0.5(H2O)2]·2.5H2O (5), and [Zn2(L)(bpe)(H2O)]·3H2O (6) [H4L = 5,5′-(p-xylylenediamino)-1,1′,3,3′-(benzenetetra-carboxylicacid), py = pyridine, bpy = 4,4′-dipyridine and bpe = 1,2-bis(4-pyridyl)ethane],have been synthesized by employing a flexible tetracarboxylic acidH4L and different auxiliary pyridine-based ligands. In 1–6, all L4–ligandsare 4-connected nodes; however, the diverse configurations of thetwo terminal isophthalate units of L4–around thecentral −NHCH2PhCH2NH– spacerlead to various topological nets. 1shows a three-dimensional(3D) 2-fold interpenetrated 4-connected dianetwork resultingfrom the vertical configuration of the two isophthalate units of L4–. 2displays a 3D (4,4)-connected ptsnet in which the two isophthalate units of L4–adopt a parallel configuration. The two isophthalate units of L4–in 3are also almost parallel, resultingin an intriguing 3D 2-fold interpenetrated network with the (4,4)-connected bbfnet. 4is a two-dimensional bilayer structure,extending into a 3D supramolecular framework through interlayer hydrogen-bondinginteractions. 5and 6disclose similar 3Dstructural architectures, in which the two isophthalate units of L4–are almost vertical and exhibit tetrahedral topologicalnodes, inducing a rare (4,5)-connected xwwnet and anunprecedented (4,6)-connected network, respectively. The thermal stabilitiesand luminescent properties of 1–6have also been studied in detail. The complexes exhibit intensesolid-state fluorescent emissions at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: Five novel transition metal (Zn, Cd, Mn and Co)-based coordination polymers 1–5 with a flexible rodlike N,N′-donor ligand (bbi=1,1′-(1,4-butanediyl)bis(imidazole))and four O-donor polycarboxylate anions (H2oxa=oxalic acid; H2fma=fumaric acid; H2bpdc=2,2′-biphenyldicarboxylic acid; H4cit=citric acid) have been successfully synthesized and characterized by elemental analysis, IR spectra, and X-ray diffraction, namely {[Zn(bbi)3(NO3)]Br·2H2O} n (1), [Zn(oxa)(bbi)] n (2), [Mn(fma)2(bbi)2(H2O)2] n (3), [Cd2(bpdc)2(bbi)2] n (4) and {[Co8(cit)4(bbi)6(H2O)10]·7H2O} n (5). Compounds 1–5 display various coordination motifs due to different conformations of the bbi ligand, at the same time, owing to diverse coordination modes of the polycarboxylate ligands. And the effect of the polycarboxylate ligands plays important roles in the construction of extended networks. Compounds 1, 2 and 5 all exhibit 2D layer structures, in which 1 displays a 3-fold interpenetration framework containing 2D networks with (6,3) topology and 2 is a 2D structure with (4,4) topology. Compound 5 contains a 2D 44 grid-like layer with (44·62) topology composed of octanuclear cobalt clusters. Two high-dimensional compounds (3D) with a microporous network, containing 1D flower-like metal–organic motifs interlinked by bbi ligands for 4 and a 3-fold interpenetrating network with 66-dia topology by considering the manganese ion as a four-connected node for 3, are observed. The biological activities of the title compounds have been studied. The results indicate that 1–5 exhibit certain selective antimicrobial activities against Escherichia coli, Staphylococcus aureus and Enterobacter aerogenes, besides, 5 exhibits more obvious radical-scavenging activities than that of bbi ligand. Furthermore, Solid-state properties of thermal stability and the photoluminescence properties at room temperature for these crystalline materials have also been investigated. [Copyright &y& Elsevier]

Abstract: Three ZnII/CdII-coordination polymers based on 2-propyl-4,5-imidazoledicarboxylate (H3pimdc), namely, [Zn(Hpimdc)H2O] n (1), [Cd(H2pimdc)2] n (2) and [Cd2(Hpimdc)2(bbi)0.5(H2O)2] n [bbi=1,10-(1,4-butanediyl)bis(imidazole)] (3), have hydrothermally been synthesized, which exhibit a systematic dimensional variation by changing the metal ions or introducing the auxiliary ligand. Complex 1 is a 1D zig-zag polymeric chain, which is finally extended into a 3D supramolecular network through (12) O–H⋯O H-bonding rings. Complex 2 shows a 2D layer comprised alternately arranged left- and right-handed helical chains. Complex 3 features a rare (3,3)-connected 83 network with opposite chiral layers in a slipped ABAB fashion. The photoluminescent properties and thermal stabilities of three complexes are also discussed. [Copyright &y& Elsevier]