Xianmin Guo

A series of coordination polymers assembled from 9,9-dimethylfluorene-2,7-dicarboxylic acid and various flexible bis(imidazole) ligands: synthesis, structures and properties

Seven new coordination polymers, namely, [Co2(mfda)2(bip)(H2O)2]·2H2O (1), [Zn2(mfda)2(bip)]·H2O (2), [Co2(mfda)2(bib)(H2O)] (3), [Zn2(mfda)2(bib)2]·(DMF)3·H2O (4), [Zn2(mfda)2(bib)] (5), [Zn2(mfda)2(bite)] (6) and [Ni4(mfda)4(bite)3(μ2-H2O)2]·4H2O (7) (H2mfda = 9,9-dimethylfluorene-2,7-dicarboxylic acid, bip = 1,3-bis(imidazole)propane, bib = 1,4-bis(imidazole)butane and bite =1,4-bis(imidazole)butene), have been synthesized and structurally characterized. Compounds 1 and 3 feature a two-fold interpenetrating framework of pcu topology. Compound 2 exhibits a three-fold interpenetrating framework of pcu topology. Compound 4 displays a four-fold interpenetrating framework of dia topology. Compounds 5 and 6 exhibit a uninodal six-connected network with unusual acs topology. Compound 7 shows a uninodal eight-connected framework with CsCl topology. The luminescence properties of compounds 2, 4, 5 and 6 were also measured.

Syntheses, structures and luminescent properties of seven metal–organic frameworks constructed with a rigid bis(imidazole) ligand and versatile carboxylate acids

Seven new metal–organic frameworks, namely, [Zn5(μ3-OH)2(bdc)2(bimf)2]·4H2O (1), [Zn(bdc)(bimf)]·2H2O (2), [Cd(bdc)(bimf)(H2O)]·2H2O (3), [Cd4(cdc)4(bimf)2(H2O)2]·2H2O (4), [Cd(cdc)(bimf)] (5), [Zn2(Hbtc)2(bimf)2]·H2O (6) and [Cd3(btc)2(bimf)3(H2O)]·2H2O (7) have been synthesized and structurally characterized (H2bdc = 1,4-benzenedicarboxylic acid, H2cdc = 1,4-cyclohexanedicarboxylic acid, H3btc = 1,3,5-benzenetricarboxylic acid and bimf = 9,9-dimethyl-2,7-bisimidazolylfluorene). Compound 1 displays a uninodal 12-connected fcu-framework based on pentanuclear zinc clusters. Compound 2 exhibits a 4-fold interpenetrating framework of SrAl2-topology. Compound 3 presents a 2-fold interpenetration of (4,4) net. Compound 4 shows a uninodal 8-connected framework of hex-topology. Compound 5 features a binodal framework of PtS-topology. Complex 6 features a binodal framework with an unusual (66)·(64·82) topology. Complex 7 defines a pentanodal framework containing 3, 4 and 8-connecting nodes. Their photochemical properties were measured.

Five new coordination polymers based on a semi-rigid dicarboxylic acid and versatile N-donor ligands: synthesis, characterization and properties

Based on a semi-rigid dicarboxylic acid and N-donor ligands with versatile conformations, five new coordination polymers, namely, [Zn(pdda)(bpy)] (1), [Ni(pdda)(bib)]·H2O (2), [Ni(pdda)(bpp)] (3), [Cd2(pdda)2(bit)(H2O)2] (4) and [Mn4(pdda)4(phen)2]·H2O (5) (H2pdda = 4,4′-(1,3-phenylenedioxy)dibenzoic acid, bpy = 2,2′-bipyridine, bib = 1,4-bis(imidazole)butane, bpp = 1,3-bis(4-pyridyl)propane, bit = 1,4-bis(imidazol-1-ylmethyl)benzene, phen = 1,10-phenanthroline), have been synthesized under hydrothermal conditions. Their structures have been characterized by single-crystal X-ray diffraction analysis, elemental analysis, IR spectroscopy and thermogravimetric analysis. Compound 1 shows the interweaving of single helical chains. Compound 2 displays a polycatenane framework with the entanglement of (4,4) layers. Compound 3 exhibits a mutual incorporation of two (4,4) layers. Compound 4 is also a (4,4) layer structure which can be split into interesting double helixes. Compound 5 features a 3D framework of NbO topology. Their photochemical and magnetic properties were measured.

Seven entangled coordination polymers assembled from triphenylamine-based bisimidazole and dicarboxylates: interpenetration, self-penetration and mixed entanglement

Seven new entangled coordination polymers, namely, [Zn(sdc)(bita)] (1), [Zn(1,4-ndc)(bita)] (2), [Zn2(bdc)2(bita)2] (3), [Zn2(sda)2(bita)2] (4), [Cd(odc)(bita)]·0.5H2O (5), [Cd2(bpdc)2(bita)2] (6) and [Cd3(bpdc)3(bita)2]·2DMF (7) [bita = 4,4′-bisimidazyltriphenylamine, H2sdc = 4,4′-sulfonyldibenzoic acid, 1,4-H2ndc = naphthalene-1,4-dicarboxylic acid, H2bdc = 1,4-benzenedicarboxylic acid, H2odc = 4,4′-oxybisbenzoic acid, H2sda = 4,4′-stilbenedicarboxylic acid, H2bpdc = biphenyl-4,4′-dicarboxylic acid], have been synthesized and structurally characterized. Compound 1 exhibits a 2D → 2D polycatenane of three-fold interpenetrated sql networks. Compound 2 displays a four-fold interpenetration of a dia network in a [2 + 2] mode. Compound 3 features both polyrotaxane and polycatenane composed of two interlocked sets of hcb network. Compound 4 shows three-fold interpenetration of a pcu network. Compound 5 presents unusual two-fold interpenetration of a self-penetrating framework with (42·6·83) topology. Compound 6 displays a 2D → 3D polycatenane of three-fold interpenetrated sql networks. Compound 7 exhibits an unusual self-penetrating framework with (425·63) topology. The thermal stabilities and photochemical properties of these compounds have also been studied.

A series of entangled coordination polymers assembled by a V-shaped bisimidazole ligand and various dicarboxylic acids: synthesis, characterization and luminescence properties

Based on a V-shaped bisimidazole ligand and various dicarboxylic acids, nine entangled coordination polymers, namely, [Zn(o-bdc)(bips)]·2H2O (1), [Zn2(cdc)2(bips)2]·2H2O (2), [Zn2(bpedc)2(bips)2] (3), [Zn(odc)(bips)]·H2O (4), [Zn2(sdc)2(bips)2]·5H2O (5), [Co2(sdc)2(bips)2(H2O)]·2H2O (6), [Cd2(bpdc)2(bips)2]·3H2O (7), [Cd2(2,6-ndc)2(bips)2(H2O)2]·2H2O (8) and [Cd(1,4-ndc)(bips)]·DMF·H2O (9) (bips = bis(4-imidazol-ylphenyl)sulfone, o-H2bdc = o-phenyldicarboxylic acid, H2cdc = 1,4-cyclohexanedicarboxylic acid, H2bpedc = 4,4′-stibenedicarboxylic acid, H2odc = 4,4′-oxybisbenzoic acid, H2sdc = 4,4′-sulfonyldibenzoic acid, H2bpdc = biphenyl-4,4′-dicarboxylic acid, 1,4-H2ndc = naphthalene-1,4-dicarboxylic acid, 2,6-H2ndc = naphthalene-1,4-dicarboxylic acid), have been synthesized and structurally characterized. Compound 1 exhibits a 2D → 2D polycatenane of 3-fold interpenetrated sql layers. Compound 2 shows a 2D → 3D polycatenane of 3-fold interpenetrated sql layers. Compound 3 displays a 2D → 3D polycatenane of 5-fold interpenetrated sql layers. Compound 4 exhibits a 2-fold interpenetration of CdSO4 networks. Compound 5 presents a 2D → 3D polycatenane by three-fold interpenetrated {42·63·8}2 layers. Compound 6 features an unusual 2D → 2D polycatenane framework assembled by the entanglement of sql layers containing 2-membered loops. Compound 7 exhibits a 1D → 3D polycatenane by the 3-fold interpenetration of 3-connected ribbons. Compound 8 displays a 3-fold interpenetration of SrAl2 networks. Compound 9 exhibits a 4-fold interpenetration of dia networks in a [2 + 2] mode. Their luminescence properties were also measured.

Syntheses, characterization and luminescence properties of five entangled coordination polymers based on bis(4-imidazolphenoxy)methane and various dicarboxylic acids

Five novel entangled coordination polymers, namely, [Cd(sdc)(bipm)(H2O)]·DMF (1), [Cd2(bdc)2(bipm)2(DMF)2] (2), [Cd2(ndc)2(bipm)2]·2H2O (3), [Cd(bdc)(bipm)] (4) and [Cd2(bpdc)2(bipm)2] (5) [bipm = bis(4-imidazolphenoxy)methane, H2sdc = 4,4′-sulfonyldibenzoic acid, H2bdc = 1,4-benzenedicarboxylic acid , H2bpdc = biphenyl-4,4′-dicarboxylic acid, and H2ndc = naphthalene-2,6-dicarboxylic acid], have been synthesized and structurally characterized. Compound 1 exhibits a 2-fold interpenetration of (4,4)-connected sql network. Compound 2 displays an inclined catenation of (6,3)-connected hcb network. Compound 3 features an unusual twofold interpenetrating polyrotaxane motif composed of two interlocked sets of identical pcu nets. Compounds 4 and 5 both show 3D polycatenane motifs generated by the 2D → 2D parallel → 3D parallel interpenetration of (4,4)-connected sql network. But in 4, one net is interpenetrated by five others, while in 5, unusually, one net is interpenetrated by eight others. The thermal stabilities and photochemical properties of these compounds have also been studied.

A microporous cationic metal–organic framework for the efficient removal of dichromate and the selective adsorption of dyes from water

A unique microporous cationic metal–organic framework, namely [Cd(tipo)(HCOO)(H2O)]·NO3·DMF (1), has been synthesized and structurally characterized [tipo = tris(4-(1H-imidazol-1-yl)phosphine oxide)]. This compound exhibits rapid and selective separation of methyl orange. Meanwhile, it has also been developed as a potential adsorbent material for the efficient removal of Cr2O72− from aqueous solutions with a high uptake of up to 228 mg g−1.

Structural diversity of six metal–organic frameworks from a rigid bisimidazole ligand and their adsorption of organic dyes

Six metal–organic frameworks, namely, [Cd2(odc)2(2,6-bin)2]·(CH3)2NH (1), [Cd2(tdc)2(2,6-bin)2(H2O)2] (2), [Cd2(bzdc)2(2,6-bin)2]·4DMF (3), [Cd2(hfdc)2(2,6-bin)2]·H2O (4), [Cd3(tpo)2(2,6-bin)3(H2O)4]·2DMF·2H2O (5) and [Zn3(btb)2(2,6-bin)]·8DMF (6) {2,6-bin = 2,6-bisimidazoylnaphthalene, H2odc = 4,4′-oxybisbenzoic acid, H2tdc = thiophene-2,5-dicarboxyl acid, H2bzdc = benzophenone-4,4′-dicarboxylic acid, H2hfdc = 2,2′-bis(4-carboxyphenyl)hexafluoropropane, H3tpo = tris-(4-carboxylphenyl)phosphine oxide and H3btb = 4,4′,4′′-benzene-1,3,5-triyl-tribenzoic acid} have been synthesized and structurally characterized. Compound 1 exhibits a three-fold interpenetration of 4T25 network. Compound 2 presents a five-fold interpenetration of dia network. Compound 3 displays a 2D → 2D three-fold interpenetration of sql layers. Compound 4 features a 2D → 3D parallel polycatenation of sql layers. Compound 5 exhibits an unusual 3,4,6-connected self-catenated network of 3,4,6T206 topology. Compound 6 shows a rare 3,8-connected self-catenated network of 3,8T72 topology. Their adsorption behaviors to organic dyes have been studied.