Cationic Europium-Organic Framework for Chromatographic Column Separation of Ionic Dyes and Stimuli-Responsive Chromic Properties.

A novel 3D europium-based cationic framework (Eu-CMOF) has been constructed solvothermally by employing a viologen derivative as an organic functional building unit. Notably, Eu-CMOF demonstrates its capability as a proficient aqueous-phase ion-exchange host, facilitating the remarkable rapid chromatographic column separation of new coccine and malachite green (NC/MG), as well as new coccine and methylene blue (NC/MLB), in mere 2 to 4 min. Adsorption thermodynamics and kinetics of anionic dyes demonstrate that Eu-CMOF exhibits a higher adsorption capacity for NC, as evaluated by the Langmuir model, reaching a value of 173 mg·g.

A viologen-based Cd(II) coordination polymer as a multifunctional platform for photochromism, chemochromism and a broad range of fluorescence pH sensing.

A multi-responsive Cd(II) coordination polymer (1) has been constructed by introducing a viologen derivative as both the framework backbone and ligand side pendant. Notably, compound 1 exhibits intriguing properties, including photochromism, methanol-assisted photochromism and chemochromism to ammonia. Furthermore, compound 1 also displays fluorescence pH sensing ability in a wide pH range.

A Multifunctional Coordination Polymer Constructed by Viologen Derivatives: Photochromism, Chemochromism, and MnO Sensing.

A multifunctional Cd-based coordination polymer based on a viologen derivative and a secondary carboxylic ligand, namely, {[Cd(bcbp)(pta) (HO)]·2HO} (, HbcbpCl = 1,1'-bis(4-carboxyphenyl)-(4,4'-bipyridinium) dichloride, Hpta = -phthalic acid), has been solvothermally synthesized and structurally characterized. Compound is a 3D framework built on {Cd(pta) (HO)} net with square channels which intalls bcbp ligands at the diagonal position of the two adjacent square channels. Notably, compound exhibits a reversible photochromic transformation between yellowish gray and dark green under xenon light irradiation, which should be attributed to the formation of free viologen radicals.

Sodalite Cd-Cage-Based Metal-Organic Framework Constructed by Cd and Cd Metal-Organic Clusters.

A sodalite Cd-cage-based metal-organic framework (MOF), namely, CPM-9S, has been constructed based on Cd and Cd metal-organic clusters (MOCs), which, to the best our knowledge, represents the first Cd-cage-based MOF that contains the highest-nuclear Cd-based MOC and the largest number of Cd ions in a cage. The iodine adsorption performances in terms of the iodine adsorption capacity, adsorption isotherm, and adsorption kinetics, as well as the adsorption mechanism, have been further studied.

Cationic coordination polymers with thirteen-fold interpenetrating dia networks: selective coloration and ion-controlled photochromism.

A novel Cd-based cationic coordination polymer (Cd-CCP) constructed using viologen derivatives, which exhibits an unusual thirteen-fold interpenetrating diamondoid network, has been synthesized. Notably, Cd-CCP displays selective and naked-eye distinguished coloration and ion-controlled photochromism towards halide anions.

Viologen-Based Cationic Metal-Organic Framework for Efficient CrO Adsorption and Dye Separation.

A novel cationic metal-organic framework composed of {Cu(COO)} paddle-wheel units and a tetracarboxylic viologen derivative, namely, {[Cu(bdcbp)(HO)]·2NO·2HO} (, HbdcbpCl = 1,1'-bis(3,5-dicarboxyphenyl)-4,4'-bipyridinium dichloride), has been successfully synthesized and structurally characterized. In , the {Cu(COO)} unit and viologen derivative both act as four-connected nodes forming an ssb-type cationic network with 4.8 topology, in which the positive charges are distributed on the organic viologen moieties.

Two novel lead-based coordination polymers for luminescence sensing of anions, cations and small organic molecules.

Two novel lead-based coordination polymers, namely [Pb(cbdcp)]·0.5HO·0.5CHOH (1) and [Pb(cbdcp)] (2), have been solvothermally constructed by using a zwitterionic ligand 4-carboxy-1-(3,4-dicarboxy-benzyl)-pyridinium chloride (abbreviated as HcbdcpCl).

A new strategy for constructing a disulfide-functionalized ZIF-8 analogue using structure-directing ligand-ligand covalent interaction.

Inter-ligand van der Waals forces play a key role in the synthesis of different ZIF types. Here we report an unusual case involving covalent inter-ligand interactions through disulfide bond formation in a ZIF-8 analogue. It exhibits high CO2 uptake and stepwise adsorption of light hydrocarbons with potential applications in ethane/ethylene separation.

Extremely stable europium-organic framework for luminescent sensing of CrO and Fe in aqueous systems.

Three novel 3D lanthanide-organic frameworks, namely [Ln2L(1,3-bdc)3]·5H2O (Ln: Eu, Sm and Dy), with a 412·63 topology based on a zwitterionic ligand, 4-bis(4-carboxylatopyridinium-1-methylene)benzene dichloride (H2LCl2), and 1,3-benzene dicarboxylic acid (1,3-H2bdc) have been synthesized hydrothermally. Notably, the Ln-MOFs are extremely stable in an aqueous system and are capable of resisting acids or bases over a wide pH range from 3 to 11. Meanwhile, an Eu-MOF is further proven to be a promising dual sensor in an aqueous system toward Cr2O72- and Fe3+.

A cyano-bridged Cu(i)-based organic framework coupled with the C-C bond cleavage of acetonitrile for selective and sensitive sensing of Fe ions.

A cyano-bridged Cu(i) organic framework based on [Cu6(CN)6]n was synthesized, in which cyano anions were generated in situ from the C-C bond cleavage of acetonitrile. The as-synthesized compound displays orange-red luminescence and is further proven to be a promising Fe3+ luminescent sensor with high selectivity and sensitivity.

Open pentameric calixarene nanocage.

A novel open helmetlike coordination cage has been synthesized based on Co4-calixarene shuttlecock-like secondary building units and in situ generated phosphate anions, where the opening of the cage comprises a large 16-membered ring. The above unprecedented Co20 nanocage presents the first pentameric calixarene coordination compound. Sorption behavior and magnetic properties are also investigated.

Photophysical studies of europium coordination polymers based on a tetracarboxylate ligand.

Reaction of europium sulfate octahydrate with p-terphenyl-3,3″,5,5″-tetracarboxylic acid (H4ptptc) in a mixed solvent system has afforded three new coordination polymers formulated as {[Eu(ptptc)0.75(H2O)2]·0.5DMF·1.

A series of novel zinc(II) entangled coordination polymers based on carboxyphenyl-terpyridine ligands.

Hydrothermal synthesis has afforded five divalent zinc coordination polymers containing 4-(4-carboxyphenyl)-2,2':6',2''-terpyridine (HL1) or its isomer 4-(4-carboxyphenyl)-2,2':4',4''-terpyridine (HL2), with or without the addition of auxiliary ligands, 1,3,5-benzenetricarboxylic acid (H3btc) and 1,4-benzenedicarboxylic acid (H2bdc). Their structures have been characterized by single crystal X-ray analyses and further characterized by infrared spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses and photoluminescent spectra. Across this series, the π···π interactions have a dramatic impact on the self-assembly of these entanglement structures, in either case it can exert an important structure-directing role.

Thiacalix[4]arene-supported kite-like heterometallic tetranuclear Zn(II)Ln(III)3 (Ln = Gd, Tb, Dy, Ho) complexes.

Four kite-like tetranuclear Zn(II)Ln(III)3 (Ln= Gd 1, Tb 2, Dy 3, Ho 4) clusters supported by p-tert-butylthiacalix[4]arene (H4BTC4A) have been prepared under solvothermal conditions and structurally characterized by single crystal X-ray diffraction and powder X-ray diffraction (PXRD). In the structures of these four complexes, each of them is capped by two tail-to-tail p-tert-butylthiacalix[4]arene molecules to form a bent sandwich-like unit. The photoluminescent analyses reveal that the H4BTC4A is an efficient sensitizer for Tb(3+) ions in 2.

Visible and NIR photoluminescence properties of a series of novel lanthanide-organic coordination polymers based on hydroxyquinoline-carboxylate ligands.

A series of novel two-dimensional (2D) lanthanide coordination polymers with 4-hydroxyquinoline-2-carboxylate (H(2)hqc) ligands, [Ln(Hhqc)(3)(H(2)O)](n)·3nH(2)O (Ln = Eu (1), Tb (2), Sm (3), Nd (4), and Gd (5)) and [Ln(Hhqc)(ox)(H(2)O)(2)](n) (Ln = Eu (6), Tb (7), Sm (8), Tm (9), Dy (10), Nd (11), Yb (12), and Gd (13); H(2)ox = oxalic acid), have been synthesized under hydrothermal conditions. Complexes 1-5 are isomorphous, which can be described as a two-dimensional (2D) hxl/Shubnikov network based on Ln(2)(CO(2))(4) paddle-wheel units, and the isomorphous complexes 6-13 feature a 2D decker layer architecture constructed by Ln-ox infinite chains cross-linked alternatively by bridging Hhqc(-) ligands. The room-temperature photoluminescence spectra of complexes Eu(III) (1 and 6), Tb(III) (2 and 7), and Sm(III) (3 and 8) exhibit strong characteristic emissions in the visible region, whereas Nd(III) (4 and 11) and Yb(III) (12) complexes display NIR luminescence upon irradiation at the ligand band.

Heterometallic thiacalix[4]arene-supported Na2Ni(II)12Ln(III)2 clusters with vertex-fused tricubane cores (Ln = Dy and Tb).

Two heterometallic thiacalix[4]arene-supported complexes possess a trinary-cubane core composed of one [Ni(2)Ln(2)] cubane unit and two [NaNi(2)Ln] cubane units sharing one Ln(III) ion (Ln = Dy and Tb). Only the Dy(III) complex exhibits slow magnetic relaxation behaviour of single molecule magnet nature.

Chlorine-induced assembly of a cationic coordination cage with a μ5-carbonato-bridged Mn(II)24 core.

Chlorine caged in! The chlorine-induced assembly of six shuttlecock-like tetranuclear Mn(II) building blocks generated in situ based on p-tert-butylthiacalix[4]arene and facial anions gave rise to a novel truncated distorted octahedral cationic coordination cage with a μ(5)-carbonato-bridged Mn(II)(24) core.

A series of octanuclear-nickel(II) complexes supported by thiacalix[4]arenes.

A series of discrete complexes, [Ni(8)(BTC4A)(2)(μ(6)-CO(3))(2)(μ-CH(3)COO)(4)(dma)(4)]·H(2)O (1), [Ni(8)(BTC4A)(2)(μ(6)-CO(3))(2)(μ-Cl)(2)(μ-HCOO)(2)(dma)(4)]·2DMF·2CH(3)CN (2), [Ni(8)(PTC4A)(2) (μ(6)-CO(3))(2)(μ-CH(3)COO)(4)(dma)(4)]·DMF (3), and [Ni(8)(PTC4A)(2)(μ(6)-CO(3))(2)(μ-OH)(μ-HCOO)(3) (dma)(4)] (4) (p-tert-butylthiacalix[4]arene = H(4)BTC4A, p-phenylthiacalix[4]arene = H(4)PTC4A, dma = dimethylamine, and DMF = N,N'-dimethylformamide), have been prepared under solvothermal conditions and structurally characterized by single-crystal X-ray diffraction analyses, powder XRD, and IR spectroscopy. These four complexes are stacked by dumbbell-like building blocks with one chairlike octanuclear-nickel(II) core, which is capped by two thiacalix[4]arene molecules and connected by two in situ generated carbonato anions and different auxiliary anions. This work implied that not only the solvent molecules but also the upper-rim groups of thiacalix[4]arenes have significant effects on the self-assembly of the dumbbell-like building blocks.