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• MOFs 1–2 show a 3D supramolecular network structure with microporous. • MOFs 1–2 have abundant active sites of Lewis acid due to the fact that the metal center of MOFs 1–2 is rare earth metal. • MOFs 1–2 have good catalytic activity for the chemical fixation of carbon dioxide with epoxides under mild conditions. • MOFs 1–2 showed universality and remarkable conversion for epoxides of different sizes. The burning of a large number of fossil fuels leads to the increase of CO 2 content in the air, causing environmental problems such as greenhouse effect and ocean acidification, which has attracted wide attention. It is of great significance to utilize microporous metal-organic frameworks (MOFs) for carbon dioxide conversion and utilization. Herein, two MOFs {[Ln(dppa)(H 2 O) 2 ·2H 2 O]·dima·H 2 O·0.5O} (1: Sm-MOF; 2: Gd-MOF; H 4 dppa = 5-(3′ 4′-dicar- boxylphenoxy) isophthalic acid, dima = dimethylamine, which is decomposed by DMF hydrothermal reaction), and its structural characterization and CO 2 catalytic conversion performance were studied. The BET test of MOFs 1–2 shows that it has good microporosity. At 273 K and 298 K, MOFs 1–2 showed lower adsorption capacity for CH 4 , but higher adsorption capacity for CO 2. The adsorption enthalpy of CO 2 was calculated by Virial equation, and the adsorption selectivity of CO 2 at different separation ratios was discussed respectively. The heterogeneity of MOFs 1–2 was proved by thermal filtration experiments. The reproducibility test shows that the catalyst structure is still intact after five cycles, indicating that the catalyst still has good repeatability. In addition, the catalytic mechanism of cycloaddition reaction was discussed. The low coordination Ln-MOFs not only exhibit abundant Lewis acidsites, but also show high catalytic activity and selectivity in the CO 2 cycloaddition reaction, as well as strong recyclability and substrate versatility. In addition, the catalytic mechanism of cycloaddition reaction was discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

abstract Two novel coordination polymers (CPs), [Cd 2 (cbta)(phen) 2 (H 2 O)] n (1), {[Zn 2 (cbta)(phen) 2 ] [Zn 2 (cbta) (phen) 2 (H 2 O)]·4H 2 O} n (2) (H 4 cbta = 1-(2-carboxylphenoxy)-2,3,5-benzene tricarboxylic acid; phen = 1,10-phenanthroline), were synthesized and characterized by elemental analyses, FT-IR spectra, single-crystal X-ray diffraction analyses. CP 1 shows a 2D network structure based on tetranuclear CdII clusters and (cbta)4- ligands, which are arranged in a [ABAB···] alternation to form a 3D supramolecular structures through π···π stacking interactions. Noticeably, CP 2 contains two kinds of independent units [Zn 2 (cbta)(phen) 2 ] (A) and [Zn 2 (cbta)(phen) 2 (H 2 O)]·4H 2 O (B) to form a 1D+1D structure. A shows 1D double chain based on Zn1, Zn2, which are recognized each other to generate a 2D supramolecular network (A) by hydrogen bonding interactions. While B are ring chains comprised of Zn3, Zn4, which are linked into 2D supramolecular network (B) through π···π stacking interactions. The peculiar structural feature is that the neighboring 2D networks are arranged in a [ABAB···] alternation to form a 3D supramolecular structure through hydrogen bonding interactions and C H···π and C H⋯O week interactions. Especially the (ctba)4- ligands in 1 – 2 adopt three different conformations and coordination modes. The thermal stabilities, XRD, UV, photoluminescence properties of CPs 1–2 were also studied. Remarkably, CPs 1–2 exhibit photocatalytic activities for degradation of dye (MB) under UV light irradiation and show good stabilities toward UV-light photocatalysis. Graphical abstract Two novel d10 metal CPs have been successfully synthesized and structurally characterized. 1 is a 2D network structure based on tetranuclear CdII clusters. 2 contains two kinds of independent units [Zn2(cbta)(phen)2] (A) and [Zn2(cbta) (phen)2(H2O)]·4H2O (B) to form an 1D+1D structure. The peculiar structural feature is that the neighboring A and B chains are arranged in a [ABAB···] alternation to form 3D supramolecular structure through hydrogen bonding interactions and π ... π stacking interactions. In addition, the thermal stability, photoluminescence and photocatalysis of 1–2 were also studied. Image 1 Highlights • Two Cd/Zn CPs with H 4 cbta and phen ligands. • 1 shows a 2D network based on tetranuclear CdII clusters and (cbta)4- ligand. • 2 contains two independent units (A) and (B) to form an 1D+1D structure. • The thermal stabilities and luminescence properties were also studied. • 1–2 exhibit photocatalytic activities for degradation of dye under UV light irradiation. [ABSTRACT FROM AUTHOR]

Abstract: Two new co-crystal copper(II) melamine complexes, [Cu(HBA)2(MA)2] [Cu(HBA)2] (1) and [Cu2(OAc)4(MA)·(H2O)]2[Cu(HPE)2] (2), MA, melamine; HBA, 2-hydroxybenzaldehyde; HPE, 1-(2-hydroxyphenyl)ethanone, have been synthesized and characterized by elemental analysis, IR and single crystal X-ray diffraction. Crystal structural analysis reveals that 1 and 2 all are co-crystal complexes and composed of two neutral coordination units. In 1, two mononuclear units adopt square planar and distorted octahedral coordination environments, respectively. In 2, one is a mononuclear unit with a square planar geometry and the other is a dinuclear unit with a paddle wheel structure in which the apical positions are rarely occupied by two different donor ligands. The 2D supramolecular structures are formed through strong hydrogen bonds with different modes. The electrochemical behaviors of complexes 1 and 2 were investigated. [Copyright &y& Elsevier]

• Two new types of Zn-MOF { [Zn(CIA2−)(4,4′-BB)]·0·75H 2 O} n and Co-MOF [Co(CIA2−)(4,4′-BB)·H 2 O] n were synthesized by solvothermal method. • Zn-MOF sensor can achieve the quantitative detection of His, TC, NB and PTH with high sensitivity and selectivity. • Co-MOF can be used as a photocatalyst to photo-catalyze the basic fuchsin and methylene blue dyes. In this paper, two metal-organic frameworks { [Zn(CIA)(4,4′-BB)]·0·75H 2 O} n (1) and [Co(CIA)(4,4′-BB)·H 2 O] n (2) were synthesized by using ligands 5-methoxyisophthalic acid (5-H 2 CIA) and 4,4′-bis((1 H -imidazol-1-yl)methyl)-1,1′-biphenyl (4,4′-BB) under solvothermal conditions. The structures were characterized by TG, IR, PXRD, BET, single-crystal X-ray diffraction and elemental analysis. The results show that 1 and 2 form a three-dimensional structure, where 1 and 2 have good thermal stability. Further study reveals that 1 shows good fluorescence properties and can be used as a fluorescence sensor to detect histidine (His), nitrobenzene (NB), tetracycline (TC) and pyrimethanil (PTH) in water. (LOD: His 0.23 μM, TC 0.17 μM, PTH 0.08 μM, NB 0.03 μM). However, 2 shows better photocatalytic activity and can be used to degrade dyes in water, such as BF (basic fuchsin) and MB (methylene blue). Under visible light irradiation, the degradation rate of BF is 95.5 % and that of MB is 76.1 %. Finally, the mechanism of detection of 1 as a fluorescence probe and the mechanism of photocatalytic degradation of 2 are discussed. Zn-MOF (1) fluorescence sensor was synthesized by hydrothermal method using carboxylic acid and imidazole. The 1 as a fluorescent probe has high sensitivity, selectivity, anti-interference and circulation ability for His-TC PTH and NB. Co-MOF (2) was synthesized by the same method. It is found that 2 can be used as photocatalyst for degradation of BF and MB dyes under visible light. Finally, the detection mechanism of 1 and the degradation mechanism of 2 were discussed. [Display omitted] [ABSTRACT FROM AUTHOR]

One new heterometallic complex [Cd 2 Cu(BTC) 2 (H 2 O) 2 ]⋅2H 2 O ( 1 ) (BTC = benzene-1,3,5-tricarboxylate), has been synthesized and characterized by elemental analysis and single-crystal X-ray diffraction techniques. The structure indicates that the complex 1 crystallizes in triclinic, space group P ī, in which, the carboxylate groups of BTC ligand adopt μ 2 –η 1 :η 1 , and μ 2 –η 2 :η 1 coordination modes, bridging Cd(II) and Cu(II) atoms to generate 2D Cd-BTC bilayer then to a (4,6)-connected open 3D framework with 1D channels occupied by guest water molecules. In addition, thermal gravimetric analysis (TGA) and luminescent property of 1 were investigated. [ABSTRACT FROM AUTHOR]

• Two new zn (II) coordination polymers were synthesized and characterized. • Complex 1 and complex 2 can detect 2,4,6-Trinitrophenol (TNP), tetracycline (TET) and fluazinam (FLU) with a high sensitivity and selectivity. • Coordination polymers have shown great potential in clinical diagnosis and treatment. Two new Zn(II) coordination polymers, namely, {[Zn 2 (L)(4,4′-bip) 2 ] ·4H 2 O} n (1) {[Zn (H 2 L) (1,2-die)] · H 2 O} n (2) [H 4 L = 5, 5′-(ethane-1, 2-diyl) diisophthalic acid, 4, 4′-bip = 4, 4′ - bis (1-imidazolyl) biphenyl , 1, 2-die = 1,2-di(pyridin-4-yl)ethene] have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, IR spectra and fluorescent analysis. Coordination polymers 1 and 2 are 2D network structures. They both have 3D supramolecular structures based on the interspersion of 2D networks. They can detect 2, 4, 6-trinitrophenol (TNP), tetracycline (TET) and fluazinam (FLU) by fluorescence quenching. And the possible reasons for the quenching of TNP, TET, and FLU were discussed in detail, which may be energy resonance transfer. These new zinc coordination polymers could be used multifunctional sensors on NACs, antibiotics and pesticides in the future. In addition, the results of fluorescence sensing experiments show that Zn(II) coordination polymers composed of different auxiliary N donors have significant influence on the detection limits. [ABSTRACT FROM AUTHOR]

• Two new zn (II) coordination polymers were synthesized and characterized. • Complex 1 and complex 2 can detect 2,4,6-Trinitrophenol (TNP), tetracycline (TET) and fluazinam (FLU) with a high sensitivity and selectivity. • Coordination polymers have shown great potential in clinical diagnosis and treatment. Two new Zn(II) coordination polymers, namely, {[Zn 2 (L)(4,4′-bip) 2 ] ·4H 2 O} n (1) {[Zn (H 2 L) (1,2-die)] · H 2 O} n (2) [H 4 L = 5, 5′-(ethane-1, 2-diyl) diisophthalic acid, 4, 4′-bip = 4, 4′ - bis (1-imidazolyl) biphenyl , 1, 2-die = 1,2-di(pyridin-4-yl)ethene] have been synthesized under hydrothermal conditions and characterized by single-crystal X-ray diffraction, thermogravimetric analysis, IR spectra and fluorescent analysis. Coordination polymers 1 and 2 are 2D network structures. They both have 3D supramolecular structures based on the interspersion of 2D networks. They can detect 2, 4, 6-trinitrophenol (TNP), tetracycline (TET) and fluazinam (FLU) by fluorescence quenching. And the possible reasons for the quenching of TNP, TET, and FLU were discussed in detail, which may be energy resonance transfer. These new zinc coordination polymers could be used multifunctional sensors on NACs, antibiotics and pesticides in the future. In addition, the results of fluorescence sensing experiments show that Zn(II) coordination polymers composed of different auxiliary N donors have significant influence on the detection limits. [ABSTRACT FROM AUTHOR]

Abstract: Four new mixed-ligand complexes, namely [Zn2(pam)2(2,2′-bpy)2] (1), [Cd(pam)(2,2′-bpy)2] n (2), [Zn(pam)(phen)] n (3) and [Cd (pam)(phen)] n ·0.5n CH3CH2OH·0.5nH2O (4) (H2pam=pamoic acid, 2,2′-bpy=2,2′-bipyridine, phen=1,10-phenanthroline) have been synthesized under hydro(solvo)thermal conditions. Complex 1 possesses a discrete dinuclear metallamacrocyclic structure. Complex 2 is a 1D homochiral helical coordination polymer that is built from achiral components, whereas 3 displays a 1D helical chain structure. 4 is an unusual 2D double-layered structure generated by π⋯π interactions of two 2D networks. The structural differences of these complexes are mainly due to the differences of the size of the rigid aromatic chelate ligands and d10 metal ions. It appears that the chelate ligands and metal ions of the larger size favor the formation of high-dimensional structures, whereas those of the smaller size favor the formation of low-dimensional structures in the present system. The photoluminescence and thermal stability of these complexes were investigated. [Copyright &y& Elsevier]

Abstract: Two metal-organic coordination polymers, [Cd(dpa)(pytpy)]·(H2O)3 (1) and [Cd3(dpa)(pytpy)2(SO4)2]·(H2O)3 (2), have been synthesized by the reactions of 4′-(3-pyridyl)-2,2′:6′,2′′-terpyridine (pytpy), diphenic acid (H2dpa) with Cd(ClO4)2·6H2O and CdSO4·8/3H2O, respectively, in the presence of base. Compound 1 is a one-dimensional helical chain, in which (dpa)2− as bridging ligand is responsible for the formation of the main framework and pytpy as chelating ligand grafts on one side of the helical chain and forms π–π stacking interactions with adjacent chains. This compound is further extended into a two-dimensional supramolecular framework through hydrogen bonds. Compound 2 is a one-dimensional chain simultaneously composed of bridging neutral organic ligand, bridging anionic organic ligand and bridging anionic inorganic ligand. The (dpa)2− and sulfate anions connect CdII atoms into neutral [Cd3(dpa)(SO4)2] subunits and the trinuclear units are bridged by pytpy ligand into one-dimensional double-layer chain. This structure is further extended into two-dimensional layer architecture through face-to-face π–π interactions. [Copyright &y& Elsevier]