Yu-Hui Luo

Copper(II) and nickel(II) coordination polymers assembled from 2,4-dibenzoylisophthalic acid and different N-donor co-ligands: syntheses, crystal structures, and magnetic properties

Four new coordination polymers based on 2,4-dibenzoylisophthalic acid and different N-donor auxiliary co-ligands, {Cu2L2(4,4′-bpy)}n (1), {Ni2L2(4,4′-bpy)}n (2), {[Cu10(L)8(bbi)(μ3–OH)4(H2O)6]·4H2O}n (3) and {[CuL(bth)(H2O)]·H2O}n (4) (H2L = 2,4-dibenzoylisophthalic acid, 4,4′-bpy = 4,4′-bipyridine, bbi = 1,1′-(1,4-butanediyl)bis(imidazole) and bth = 1,6-bis(1,2,4-triazol-1-yl)hexane), have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopy, UV-Vis spectra, powder X-ray diffraction and thermogravimetric analysis. Complexes 1 and 2 are isostructural and crystallized in the chiral space groupP3221. They both possess three-dimensional (3D) coordination frameworks with 6-connected (44·510·7) topology that are incorporated left-handed helices and right-handed double helices substructures based on M(II) (M = Cu, Ni) paddle-wheel clusters. Complex 3 exhibits a 3D (4,5)-connected network with (44·62) (44·66) topology, in which dinuclear Cu2(CO2)4 clusters act as 4-connected nodes and tetranuclear [Cu4(μ3–OH)2]6+clusters serve as 5-connected nodes. Complex 4 shows a two-dimensional (2D) parallelogrammic network with (4,4) topology. The magnetic properties for 1–3 have been investigated and exhibited antiferromagnetic interaction.

A series of entangled ZnII/CdII coordination polymers constructed from 1,3,5-benzenetricarboxylate acid and flexible triazole ligands

Five new coordination polymers, namely, [Zn(HBTC)(L1)]·4H2O (1), [Zn3(BTC)2(L2)2(H2O)2]·2H2O (2), [Zn(HBTC)(L3)] (3), [Cd(HBTC)(L1)(H2O)]·H2O (4) and [Cd(H2BTC)2(L3)2]·2H3BTC (5) (H3BTC = 1,3,5-benzenetricarboxylic acid, L1 = 1,6-di(1,2,4-triazol-1-yl)hexane, L2 = 1,3-di(1,2,4-triazol-1-yl)propane and L3 = 1,3-bis((1,2,4-triazol-1-yl)methyl)benzene) have been successfully isolated under hydrothermal conditions. Compound 1 exhibits a rare 2D → 3D entangled structure with the coexistence of polycatenation and interdigitation. Compound 2 contains new trinodal (5.62)(52.6)(54.82) layers and features a 2D → 2D entangled network with the coexistence of polycatenation and polythreading motifs. Compound 3 shows a 2D → 2D polythreaded framework. When O–H⋯O hydrogen-bonding interactions are taken into consideration, the framework of 3 can be regarded as a 2-fold interpenetrating hms network. Compound 4 displays an unusual 2D → 3D interdigitated framework. Compound 5 displays a 1D chain structure. The thermal stabilities and fluorescence properties of compounds 1–5 have been investigated.

A series of coordination polymers constructed from in situ amidation ligands: syntheses, structures and luminescent properties

From the hydrothermal in situ amidation reactions of aromatic polycarboxylates and hydrazine hydrate (N2H4·H2O), four complexes, dinuclear [Cu(μ2-H3bbch)(H2O)]2·2H2O (1), 3-D grid-like [Fe3(μ5-Hbbch)2(μ2-H2O)2(H2O)2]·2H2O (2), 2-D layer [Zn(μ2-H2bbh)(μ2-N2H4)1/2(H2O)]·2H2O (3) and 3-D supramolecular structure [Cd(H2bch)2(2,2′-bpy)(H2O)2][Cd(μ2-H2bch)(2,2′-bpy)(H2O)2](H2bch) (4) have been prepared. The two different in situ amidated ligands in 1, 2 and 3, benzene-4,5-bicarboxylate-1,2-hydrazide (H4bbch) and benzene-1,2,4,5-bihydrazide (H4bbh), were formed through adjusting the ratios of pyromellitic acid (PMA) and N2H4·H2O, of which H4bbch was generated through hydrothermal in situ amidation reactions for the first time. Benzene-4-carboxylate-1,2-hydrazide (H3bch), displaying three new coordination modes in 4, was also an in situ amidation product of benzene-1,2,4-tricarboxylic acid (H3btca) and N2H4·H2O. 1–4 were characterized by elemental analysis, infrared spectroscopy, and thermogravimetric analysis. Their structures were determined by single-crystal X-ray diffraction. The fluorescence properties of compounds 1, 3 and 4 were also investigated.

Temperature-dependent assembly of two 3D [BW12O40]5−-based coordination polymers with visible light driven photocatalytic properties

Two new 3D coordination polymers, namely, [CuII3Cl(BBTZ)5(BW12O40)(H2O)2]·6H2O (1) and [CuI3CuII(BBTZ)5(BW12O40)(H2O)]·H2O (2) (BBTZ = 1,4-bis(1,2,4-triazol-1-lmethyl)benzene), have been successfully synthesized under hydrothermal conditions. Compound 1 is a 3D architecture with octa-nuclear water clusters while compound 2 is a 1D + 3D → 3D interpenetrated framework, which represents the first example of a POM-based coordination polymer with the co-existence of self-catenation and poly-threading. The structure–property correlations between the title compounds have been discussed. Compound 2 with narrow band-gap size exhibits more favorable efficiency of photocatalytic activity under visible light irradiation than compound 1.

Three Novel Polymeric CoII/CuII Complexes Assembled from 5-Nitro-1,2,3-benzenetricarboxylate and 4,4'-Bipyridine: Syntheses, Crystal Structures, and Magnetic Properties

To investigate the coordination behaviour of tricarboxylate ligands that always induced the formation of intriguing metal organic frameworks, three CoII/CuII complexes constructed with bi-/tri-nuclear secondary building units (SBUs), namely CoII3(O2N-btc)2(4,4′-bpy)3(H2O)2 (1), [CuII3(O2N-btc)2(4,4′-bpy)2(H2O)2]·2H2O(2) and [CuII5(O2N-btc)2(O2N-btcH)2(4,4′-bpy)2(μ2 -OH2)2(H2O)8]·4H2O(3) (O2N-btcH3 = 5-nitro-1,2,3-benzenetricarboxylate, 4,4′-bpy = 4,4-bipyridyl), were hydrothermally synthesized using O2N-btcH3 and 4,4′-bpy as ligands. Complexes 1 and 2 exhibit the 3D framework constructed from a binuclear [M2(COO)2] (M = CuII and CoII) unit and a mononuclear MII unit, displaying (4·6·8)2(64·82) (42·68·83·102) and (4·6·8)2(62·84) (42·62·810·12) topology, respectively. Complex 3 displays an interesting 2D ladder-layered network constructed from a trinuclear [Cu3(μ2-OH2)2] unit and a mononuclear CuII unit as the linking nodes, showing (42.6)2(46.66.83) nets. These compounds are well characterized by elemental analysis, FTIR, thermogravimetric analysis and powder X–ray diffraction. The direct current magnetic susceptibility measurements were carried out to study their magnetic properties.

Coordination polymers of lanthanide complexes with benzene dicarboxylato ligands

Three kinds of coordination polymers of lanthanide complexes with benzene dicarboxylato ligands, [Ln(L1)1.5(H2O)2]·H2O (H2L1 = 2,5-dibenzoylterephthalic acid; Ln = Pr (1), Nd (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7)), [Ln(L2)(phen)(OH)] (H2L2 = 4,6-dibenzoylisophthalic acid; phen = 1,10-phenanthroline; Ln = Sm (8), Eu (9), Tb (10), Dy (11), Er (12), Yb (13)) and [Ln(L1)0.5(L2)(H2O)2] (Ln = Er (14), Ho (15)), were synthesized under hydrothermal conditions. They were characterized by elemental analysis, IR spectroscopy and thermogravimetric analysis. Their solid-state structures were determined by single-crystal X-ray diffraction. Complexes 1–7 are isostructural, each featuring the L1 connected dinuclear unit of Ln2O2(CO2)6 to produce a 6-connected 3D network with (412·63) topology. Isostructural complexes 8–13 possess 2D layer structures consisting of left- and right-handed helical chains that are further assembled into 3D supramolecular architectures through C–H⋯O, C–H⋯π and π⋯π interactions. Complexes 14 and 15 display 2D layer structures, and are further linked into 3D supramolecular architectures through C–H⋯O and π⋯π interactions. The luminescence properties of 3, 4 and 6–11 were investigated.

An eight-connected porous metal–organic framework based on hetero pentanuclear clusters

A new MOF based on hetero pentanuclear clusters, [(CH3)2NH2]1.66[Cd1.84Na0.66(BDC)3]·DMF·0.5EtOH (1), has been prepared. Iodine adsorption studies reveal that 1 can reversibly adsorb iodine. Furthermore, electrochemical impedance spectroscopy (EIS) of 1⊃I2 shows that it has a relatively high conductivity at room temperature.

Assembly of three stable POM-based pillar-layer CuI coordination polymers with visible light driven photocatalytic properties

Three new POM-based pillar-layer CuI coordination polymers (CPs), CuI12Cl(trz)8[PW12O40] (1), CuI12Cl(trz)8[PMo12O40] (2) and CuI12Cl(trz)8[HSiW12O40] (3) (trz = 1,2,4-triazole), have been hydrothermally synthesized. Characterized by single-crystal X-ray diffraction analyses, compounds 1–3 are isostructural, and copper ions coordinate with trz to form double layers with the help of Cl ions, which are supported by POMs to a 3D framework with continuous channels. The same two frameworks interwine to form a 3D two-fold interpenetrating network. The compounds display high heat stability and excellent acid and alkali resistance. Ultraviolet-vis diffuse-reflectance spectra suggest that compounds 1–3 exhibit their nature of semi-conductivity. Thus, reactions of photocatalytic degradation of organic dye were performed, and its relevant photocatalytic mechanism was also finely investigated. All the title compounds show efficient visible-light-driven photocatalytic activities in the degradation of organic dyes. Moreover, hydroxyl radicals (˙OH) are proved to play a crucial role in visible photocatalytic degradation reaction.

An ultrastable, flexible POM-based coordination polymer with redox properties

A new flexible coordination polymer based on the Keggin-type structure H3PW12O40·xH2O, [Cu(L)2(H2O)H(PW12O40)]·7H2O (1), has been prepared. The framework of 1 shows dynamic behavior accompanied with the removal/adsorption of guest water molecules. Compound 1 can remain intact even in 8 mol L−1 hydrochloric acid, dilute NaOH solution (pH = 12) and boiling water.

Solvothermal synthesis, structure, and luminescence of a 3-D Cd(II) complex assembled with biphenyl-2,5,2′,5′-tetracarboxylic acid involving in situ ligand reaction

A 3-D metal-organic framework [Cd3(L)2(DMF)2] · 2H2O · 2DMF (1) (H3L = 2-(dimethylcarbamoyl)biphenyl-5,2′,5′-tricarboxylic acid, DMF = N,N-dimethylformamide) with trinuclear Cd(II) units has been prepared. Complex 1 is a (3, 6)-connected (42 · 6)2(44 · 62 · 88 · 10) coordination net, which results from the solvothermal in situ formation of a new asymmetric ligand, 2-(dimethylcarbamoyl)biphenyl-5,2′,5′-tricarboxylic acid (H3L), through amidation of biphenyl-2,5,2′,5′-tetracarboxylic acid (H4bptc). Additionally, the luminescence of 1 has been investigated.