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A scandium-based coordination polymer (Sc-CP), Sc(ox)1.5(H2O)2·4H2O (1) (H2ox = oxalic acid), with a two-dimensional (2D) layered structure was prepared by both hydrothermal synthesis and ultrasound-assisted heating methods using glutaric acid as a modulator. Then, the single crystal of 1 as a precursor was transformed into another 2D Sc-CP, Sc(ox)1.5(H2O)2·H2O (2), by increasing the temperature. Due to the difference in hydrogen bond interactions between the host framework and guest water molecules, 2 showed good tolerance to various solvents, while 1 exhibited poor stability even exposed in air. After activation, 2 could be used as a heterogeneous Lewis acid catalyst for two classic C–C bond formation reactions, the cyanosilylation reaction and Strecker reaction at room temperature, showing excellent catalytic activity and selectivity. [ABSTRACT FROM AUTHOR]

The solvothermal reaction of Mn(II) salts and 5-((4′-(tetrazol-5′′-yl)benzyl)oxy)isophthalic acid (H3L) affords an Mn(II) based coordination polymer Mn(H2L)2(H2O)2 (1), which possesses a one-dimensional (1D) chain structure. Using 1 as the precursor, three Mn(II) metal–organic frameworks, Mn3L2(2,2′-bpy)2·5H2O (2), Mn3L2(H2O)4 (3), and Mn4L2(HL)(H2O)5·0.5H2O (4), with three-dimensional (3D) networks can be obtained by different strategies of crystal transformation. Upon introduction of 2,2′-bipyridine (2,2′-bpy) as the ligand and 2,2′-biquinoline-4,4′-dicarboxylic acid as the structural-directing agent, 1 undergoes irreversible crystal transformation into 2 and 3, respectively, and 1 can be transformed into 4 by increasing the reaction temperature. Interestingly, the irreversible structural transformation of 3 into 2 can be carried out by adding a 2,2′-bpy ligand. Notably, after the removal of coordinated water molecules, 1 and 3 exhibit good catalytic performance for the cyanosilylation reaction even at 0 °C. [ABSTRACT FROM AUTHOR]

Two scandium coordination polymers (Sc-CPs), [Sc(L1)2(DMF)] (DMF = N,N′-dimethyl formamide, H2L1 = pyrazine-2,3-dicarboxylic acid) (1) and [Sc(L2)(C2O4)0.5(H2O)2]·H2O (H2L2 = pyrazine-2,5-dicarboxylic acid) (2), were prepared via hydrothermal and microwave (MW) heating techniques. It is noted that MW heating can effectively accelerate the reaction compared with a conventional hydrothermal method and decrease the crystal size of the samples. 1 shows a 1D non-planar double chain, while 2 exhibits a brick-like 2D network. After activation, 1 and 2 exhibit good catalytic performance for the cyanosilylation reaction of aromatic aldehydes; in addition, the catalysts prepared by the MW method exhibit better catalytic activity compared with those synthesized by the conventional hydrothermal method. [ABSTRACT FROM AUTHOR]

Based on flexible 5-(4-pyridyl)-methoxylisophthalic acid ligand (H2L), three layered cadmium coordination polymers, namely [CdL(H2O)]·2H2O (1), [CdL(H2O)(4,4′-bipy)0.5]·H2O (2) (4,4′-bipy = 4,4′-bipyridine), and [CdL(H2O)2]·0.5H2bdc (3) (H2bdc = 1,4-benzene dicarboxylic acid), have been prepared by a rapid microwave (MW)-assisted solvothermal synthesis method. It is noteworthy that the MW-assisted method can effectively accelerate the reaction rate compared with a conventional solvothermal method. 1 exhibits a 2D layer with the quadrangle windows built from dinuclear [Cd2N2O10] SBUs and L2− ligands. 2 shows an interesting two-fold interpenetrated 2D layered structure, in which the 4,4′-bipy ligands link the adjacent sheets constructed from Cd2+ cations and L2− ligands to build a double-layered structure with rhombic windows. For 3, the Cd2+ ions are linked with L2− ligands to form a 2D layer and free H2bdc ligands penetrate into the rhombic windows of the adjacent layers. Moreover, the activated samples of 1, 2 and 3 possess excellent luminescence sensing properties for Fe3+ ions in aqueous solution with high sensitivity and selectivity, respectively. [ABSTRACT FROM AUTHOR]

Three layer-structured coordination polymers (CPs), namely, [Pb2(TZI)(μ3-OH)(H2O)·(H2O)]n (1), [Pb(HTZI)(phen)·(H2O)]n (2) and [Zn2(TZI)(μ3-OH)(H2O)2·(1/2H2O)]n (3) have been constructed from the 5-(1H-tetrazol-5-yl)isophthalic acid (H3TZI) ligand. Notably, 1 can function as a host for the encapsulation of lanthanide(iii) ions by encapsulating different Ln3+ ions. As-prepared Ln3+@1 materials show tunable luminescent emission including white-light emission. Moreover, 1 exhibits highly luminescent sensing properties for small organic molecules. [ABSTRACT FROM AUTHOR]

Two new isostructural lanthanide coordination polymers (Ln-CPs) [Ln 2 (bpdc) 3 (DMF) 2 ] (Ln = Tb for 1 , Eu for 2 ) with two kinds of one-dimensional channels along the a axis, were synthesized by 2,2′-bipyridyl-4,4′-dicarboxylic acid (H 2 bpdc) under solvothermal conditions. With exposed Lewis acid Ln 3+ centers, 1 as a heterogeneous catalyst shows good catalytic reactivity and selectivity for the Strecker reaction affording medium to excellent conversion yields. Luminescent studies illustrate that 1 and 2 show intensive green and red luminescence triggered by efficient antenna effect of ligands under UV light, respectively. Moreover, 1 exhibits sensitive fluorescent response to Cu 2+ in DMF solution. [ABSTRACT FROM AUTHOR]

A series of lanthanide coordination polymers (LnCPs), namely [Ln(TZI) (H2O)5]n (1–5) [Ln = Nd (1), Eu (2), Gd (3), Tb (4) and Sm (5)], were synthesized through the self-assembly of 5-(1H-tetrazol-5-yl)isophthalic acid (H3TZI) ligand and lanthanide ions. X-ray crystallographic analysis reveals that compounds 1–5 are isostructural, featuring a 1D double-chain structure. The luminescence spectra in the solid state reveal that compounds 2 and 4 exhibit the characteristic luminescence of Eu(iii) and Tb(iii) ions, respectively, while compound 3 exhibits much enhanced blue-green emission which is derived from the H3TZI ligand. Further, by introducing single dopant Eu(iii) and codopants Eu(iii)/Tb(iii) into the Gd(iii) framework, white light emission and color-tunable luminescence from yellow to blue were realized. [ABSTRACT FROM AUTHOR]

• A new 3D manganese-organic frameworks (1) constructed by semi-rigid 5-((4′-(tetrazol-5′'-yl)benzyl)oxy)isophthalic acid has been synthesized. • 1 possesses left- and right- hand helical O-Mn-O chains constructed from trinuclear Mn 3 O 13 N 2 units by sharing vertex and eadge along b axis. • 1 shows high stability under different pH conditions and various organic solvents. • 1 exhibits excellent catalytic properties for cyanosilylation and knoevenagel condensation reactions of various aldehydes under solvent-free condition at room temperature. A new three-dimensional manganese-based metal–organic framework Mn 4 L 2 (HL)(H 2 O) 5 , (1), based on semi-rigid 5-((4′-(tetrazol-5′'-yl)benzyl)oxy)isophthalic acid ligand (H 3 L) have been prepared and characterized under solvothermal condition. In the structure of 1 , trinuclear Mn 3 O 13 N 2 units are linked each other by sharing vertex and edge to form left- and right- hand helical O-Mn-O chains along b axis, then adjacent left and right handed helical chains are interconnected by L3− and HL2− ligands to generate a 2D layer and L3− ligands with mode II connect the neighboring layers to form a 3D network. 1 shows high stability under different pH conditions and various organic solvents. After activation, 1 exhibits excellent catalytic properties for two typical C C bond reactions, cyanosilylation and Knoevenagel condensation reaction of aldehydes, under solvent-free conditions at room temperature. [ABSTRACT FROM AUTHOR]

[Display omitted] • A 3D Eu-MOF (1) based on H 4 DPB ligand has been successfully synthesized and characterized. • 1 could be used as selective and sensitive chemical sensor for hemin and p-nitrophenol detection. • Using 1 as filter and PVDF as matrix, 1 @PVDF has been fabricated and can be used for hemin and p-nitrophenol sensing. A new lanthanide metal–organic framework (Ln-MOF) {[Eu(DPB)(H 2 O)](Me 2 NH 2 +)} n (1) (H 4 DPB = (1,1′:3′,1′'-terphenyl)-3,3′',5,5′'-tetracarboxylic acid）was synthesized under solvothermal conditions and presented a fascinating three-dimensional (3D) framework with 4,8-connected diamond topology, which were built from Eu3+ ions and tetra carboxylate groups. 1 showed strong red luminescence emission in the solid state at room temperature and exhibited good stability in different solvents. 1 could be used as a multi-responsive luminescent sensor for hemin and p-Nitrophenol (4-NP) with detection limits of 3.91 × 10−6 M and 1.98 × 10−4 mM, respectively. Moreover, using 1 as a filler and poly (vinylidene difluoride) (PVDF) as matrix, a mixed matrix membrane 1 @PVDF was successfully prepared. 1 @PVDF also exhibited fluorescence emission comparable to that of 1 and could be used for hemin and 4-NP sensing with good selectivity and remarkable recyclability. [ABSTRACT FROM AUTHOR]

Graphical abstract Tunable luminescence from green to red was successfully achieved by co-doping Eu into isostructural Tb framework. White-light emission was successfully realized by co-doping Eu/Tb into analogic Gd framework. Abstract Three new compounds (Ln–CPs) [Ln(PPDA)(C 2 O 4) 0.5 (H 2 O) 2 ] n · n H 2 O (Ln = Tb (1), Eu (2) and Gd (3)) were synthesized based on semirigid ligand 4-(pyridin-3-yloxy)-phthalic acid (H 2 PPDA) under solvothermal conditions. Ln–CPs 1 – 3 exhibit isomorphic 2D layered network with rhombic windows. Notably, oxalic acid in the resulting framework is formed by in situ reaction under solvothermal and acidic conditions. Solid state luminescent studies indicate that 1 and 2 show characteristic green and red emissions of the corresponding Ln3+ ions, respectively, while 3 exhibits blue emission arising from PPDA2− ligand. Then, by adjusting the co-doping ratio of different Ln3+ ions into the well-defined host framework, a series of codoped Ln–CPs Eu3+-doped 1 and Eu3+, Tb3+-doped 3 are synthesized, showing tunable luminescence emissions including white-light emitting. [ABSTRACT FROM AUTHOR]

Two zinc(II) coordination polymers (CPs), namely, {[Zn 2 (µ 5 -tzbt)(µ-trz)]·3.5H 2 O} n (trz = 1,2,4-triazolate) (1) and {[Zn 2 (µ 5 -tzbt)(µ-OH)(phen)]·4H 2 O} n (phen = 1,10-phenanthroline) (2) have been constructed from 1-(triazol-1-yl)-2,4,6-benzene tricarboxylic acid (H 3 tzbt) under hydrothermal conditions. Single crystal X-ray diffraction analysis reveals that 1 displays 3D framework containing left - handed and right - handed helical chains, whilst 2 is a 2D layered structure. These new CPs both exhibit intensive fluorescence emission at room temperature. Notably, they perform as host for the encapsulation of Ln(III) ions and serve as an antenna to sensitize Tb(III) ions. By encapsulating different Ln(III) ions, both Eu 0.2 Tb 0.8 @ 1 and Eu 3+ @ 2 present white-light emission. In addition, 2 exhibits highly luminescent sensing properties for acetone. [ABSTRACT FROM AUTHOR]

Abstract: Two new zinc-triazole-biphenyldicarboxylate frameworks based on secondary building units (SBUs), namely, Zn4(μ4-O)(trz)2(4,4′-bpdc)2 ( 1 ) and Zn2(trz)2(2,4′-bpdc) ( 2 ), [Htrz = 1,2,4-triazole, H2bpdc = biphenyldicarboxylate] have been synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction analyses, X-ray power diffraction, elemental analyses, infrared absorption spectra, and thermogravimetric analyses. Compound 1 is a 2-fold interpenetrating diamond topology constructed from [Zn4(μ4-O)(trz)2]4+ SBUs with tetrahedral [Zn4(μ4-O)] core and two trz ligands. Compound 2 is a 2D 6-connected hxl network based on [Zn2(trz)2]2+ SBUs. Additionally, these two compounds show emission properties at room temperature in the solid state. [Copyright &y& Elsevier]

A new anionic indium coordination polymer, (Me 2 NH 2)[In(OH-BDC) 2 ]·H 2 O (1), has been designed and synthesized under solvothermal conditions based on organic ligand 5-hydroxyisophthalic acid. 1 exhibits a 2D layered structure with rhombic windows, which is stacked to form 3D supramolecular network by the π-π stacking interactions of phenyl rings of ligand in adjacent layers. It not only shows excellent resistance to acid or basic conditions but also has good tolerance to various common solvents. Moreover, due to the negative charge of the host framework, it shows remarkable selective adsorption for positive charge dyes such as methylene blue (MB), rhodamine B (RhB) and crystal violet (CV), and the removal rates are higher than 90%. In particular, the adsorption capability of 1 to RhB is higher than most CPs based adsorbents. In addition, MB@ 1 is a high-efficiency reactive oxygen species (ROS) producer with good photocatalytic activity for the oxidation of 1,5-dihydroxynaphthalene (1,5-DHN) and can be recycled five times without loss of activity. To our knowledge, it is the first time that dye@CP was used for ROS production and photooxidation of 1,5-DHN. Image 1 • A new 2D layer anionic Indium coordination polymer has been prepared and characterized under solvothermal condition • In the structure of 1 , there is a rhombic windows along c axis, and the layers are stacked to form 3D supramolecular network • Negative charge of 1 host framework shows remarkable adsorption property for positive charge dyes. • MB@ 1 is a high-efficiency ROS producer for the oxidation of 1,5-dihydroxynaphthalene [ABSTRACT FROM AUTHOR]

Sc-CP 1 , 1A , 1B and 1C with controllable morphologies were successfully synthesized by the conventional hydrothermal method and microwave (MW) assisted hydrothermal method. 1 was macroscopic, 1A was nano sized, while 1B and 1C were micron sized. Sc-CP 1 showed two-dimensional (2D) layered structure which was constructed from the connections of left- and right-hand helical chains. Catalytic experiments showed the catalytic performances of Sc-CP 1 , 1A , 1B and 1C for the cyanosilylation reaction of aromatic aldehydes were dependent on the morphologies of the particles. Flower-ball-like 1C featuring a high concentration of Lewis acidic Sc(III) sites on its exposed external surfaces showed better catalytic activity than others, the best constant rate of which was 6.4 ​× ​10−3 min−1. 2D layered Sc-CPs with tunable morphologies were synthesized by conventional and MW-assisted hydrothermal methods and their catalytic performance for cyanosilylation reaction of aromatic aldehydes was dependent on the morphology and size of the particles. Image 1 • A Sc-CP were synthesized through conventional hydrothermal method and Microwave-assisted method. • Microwave-assisted method is environmental friendly and energy saving. Notably, it could reduce the synthesis time obviously. • Four morphologies of the Sc-CP- 1 were obtained by controlling the conditions of synthesis procedures. • Catalytic performance of the Sc-CP- 1 for cyanosilylation reaction was dependent on the morphology and size of the particles. [ABSTRACT FROM AUTHOR]