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A new coordination polymer, namely, {[Zn(DTPP)(H2O)2]·H2O}n (H2DTPP = 3-(3,5-di(2H-tetrazol-5-yl)phenoxy)pyridine, compound 1), was successfully assembled by using a new semirigid tripodal nitrogen-containing heterotopic ligand and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectroscopy, TG, and luminescence. X-ray single-crystal diffraction analysis revealed that compound 1 crystallizes in an orthorhombic crystal system with space groups of Ibca. It is a 2D coordination network with (4·82) topology, and the 2D networks are further connected by hydrogen bonds between coordinated water molecules and tetrazole N atoms to form a 3D supramolecular framework. Moreover, compound 1 exhibits intense blue emission centered at 345 nm upon excitation at 276 nm and has the ability to sense Fe3+ via photoluminescence quenching. A new coordination polymer synthesized from a new semirigid tripodal nitrogen-containing heterotopic ligand, {[Zn(DTPP)(H2O)2]·H2O}n, was characterized. [ABSTRACT FROM AUTHOR]

A strategy for constructing binary metal–organic cage (MOC)-based materials was developed. The cationic MOCs were covalently linked by organic linkers to a cationic extended network, whereas the anionic MOCs acted as counterions and were encapsulated in the network. Compared with the corresponding unary materials, the binary MOC-based materials exhibited improved porosity and adsorption performance. [ABSTRACT FROM AUTHOR]

A Zn(II) coordination polymer (CP), namely, {[Zn(DTPB)]·DMF}n (H2DTPB = 1-(3,5-di(2H-tetrazol-5-yl)phenyl)-1H-benzeimidazole, Zn-DTPB), was assembled from a new tetrazolyl–benzimidazolyl heterotopic triangular ligand. In Zn-DTPB, the tetrazolyl groups connect the Zn(II) ions into a 2D network with a (4·82) topology, and the 2D network is further interconnected by Zn–N bonds between Zn(II) and benzimidazolyl groups to a 3D framework featuring a 4-connected sra topology. The DMF molecules were tightly encapsulated in the framework and could not be released until the framework decomposed. The framework is stable up to 300 °C and can be retained in water for 72 h. The luminescence in the solid-state and in various solvents was investigated, implying that Zn-DTPB can be used to detect acetone and triethylamine (TEA) in water by fluorescence quenching with good sensitivity and selectivity. Moreover, Zn-DTPB exhibited excellent reproducibility in sensing acetone. Mechanistic studies have shown that the fluorescence quenching of acetone and triethylamine is caused by competitive absorption and structural amorphization, respectively. Interestingly, the amorphous product can be transformed into Zn-DTPB crystals through a solvent-media structural transformation process. [ABSTRACT FROM AUTHOR]

For the first time, hierarchical porous amorphous metal–organic frameworks (HP-aMOFs) containing ultramicropores, micropores, and mesopores were synthesized by etching a composite of MOF glass (agZIF-76) and ZnO using ammonia. These materials show potential applications in the adsorption of C2 hydrocarbons. [ABSTRACT FROM AUTHOR]

The research on amorphous metal–organic frameworks (aMOFs) is still in its infancy, and designing and constructing aMOFs with functional pores remains a challenge. Two aMOFs based on Co(II) and heterotopic triangular ligands with large conjugated aromatic planes, namely aMOF-1 and aMOF-2, were constructed and characterized by IR, XPS, EA, ICP, XANS and so on. aMOF-1 possesses mesopores, whereas aMOF-2 possesses micropores. The porosity, conjugated aromatic plane and uncoordinated N atoms in the framework allow these aMOFs to adsorb iodine and dyes. The iodine adsorption capacity of aMOF-1 is 3.3 g per g, which is higher than that of aMOF-2 (0.56 g per g), mainly due to the expansion or swelling of aMOF-1 after iodine adsorption. The uptake of cationic dyes by aMOF-2 showed more rapid kinetics and a higher removal rate than that by aMOF-1, mainly due to the difference in the porosity and surface charge. Although the surface charges of aMOF-1 and aMOF-2 are negative, both of them showed significantly faster adsorption kinetics toward anionic dyes, among which methyl orange (MO) and Congo red (CR) can be removed in 5 min. This occurs possibly because the quick adsorption of Na+ ions alters the surface charge of the framework and promotes dye uptake. The adsorption capacities of aMOF-1 for MO and CR reached 921 and 2417 mg g−1, respectively. The correlation data for aMOF-2 are 1042 and 1625 mg g−1, respectively. All adsorption capacities are among the highest compared to many cMOFs. Adsorption in mixed dye solution is found to be charge-dependent, kinetic-dependent, and synergetic in these systems. The porosity, surface charge regulation during adsorption, weak interactions and multiple adsorption processes contribute to the dye adsorption performance. [ABSTRACT FROM AUTHOR]

A metal–organic cage (MOC)-based porous salt composed of cationic Zr-MOC and anionic Cu-MOC was incorporated into SBA-15 nanopores via a two-step impregnation method for the first time. The encapsulated MOC-based porous salt showed improved iodine adsorption capacity when compared with the bulk sample. [ABSTRACT FROM AUTHOR]

Mixed-ligand metal–organic frameworks (MOFs) are usually synthesized from two or more organic ligands as initial reactants, and MOFs synthesized from one organic ligand precursor through partial in situ reactions remain very limited. Herein, by introducing an imidazole-tetrazole bifunctional ligand, 5-(4-imidazol-1-yl-phenyl)-2H-tetrazole (HIPT), as a single ligand and performing in situ hydrolysis of the tetrazolium group, a mixed-ligand Co(II)-MOF based on HIPT and 4-imidazol-1-yl-benzoic acid (HIBA), [Co2(μ3-O)(IPT)(IBA)]·x solvent (Co-IPT-IBA), was constructed and applied to capture I2 and methyl iodide vapours. Single crystal structural analyses reveal that Co-IPT-IBA exhibits a 3D porous framework with 1D channels based on the relatively few reported ribbon-like rod SBUs. The nitrogen adsorption–desorption isotherms indicate that the BET surface area of Co-IPT-IBA is 168.5 m2 g−1 and it possesses both micropores and mesopores. Due to its porosity, nitrogen-rich conjugated aromatic rings, and Co(II) ions, Co-IPT-IBA was applied to capture iodine molecules in vapour and exhibited an adsorption capacity of 2.88 g g−1. By combining the IR, Raman, XPS and grand canonical Monte Carlo (GCMC) simulation results, it was deduced that the tetrazole ring, coordination water molecules, and the redox potential of Co3+/Co2+ facilitate iodine capture. The presence of mesopores was also responsible for the high iodine adsorption capacity. In addition, Co-IPT-IBA showed the ability to capture methyl iodide in vapours with a moderate capacity of 625 mg g−1. The transformation of crystalline Co-IPT-IBA to amorphous MOFs may be due to the methylation reaction. This work represents a relatively rare example of methyl iodide adsorption by MOFs. [ABSTRACT FROM AUTHOR]

Two Cu(I) coordination polymers (CPs), namely, [CuI(DBPT)(H2O)]n (HDBPT = 3,5-di((1H-benzeimidazol-yl)phenyl)-2H-tetrazole, CP 1) and [CuI(DBPT)·DMF]n (CP 2), were constructed based on a new N-containing heterotopic triangular ligand. CP 1 is a 2D network consisting of binuclear secondary building units (SBUs). The 2D layers are connected by strong hydrogen bonds to form a 3D supramolecular framework. CP 2 possesses a 3D framework based on binuclear SBUs and features a (3,6)-connected rtl topology. Both CP 1 and CP 2 have high stability in water in the pH range from 3–13 and exhibit energy band gaps of 2.70 and 2.79 eV, respectively, which indicate their possibility in visible-light-driven photocatalysis. The photocatalytic results show that both CP 1 and CP 2 display good activity for MLB degradation in the presence of H2O2 as an oxidant under visible light irradiation. A mechanistic investigation indicated that the photogenerated holes trapped by Cu(I) generate Cu(II). Cu(II) may be involved in a Fenton-like CuI/CuII redox reaction to generate ˙OH. Thus, holes and ˙OH contribute to the degradation of MLB. In addition, the degradation product of MLB was further studied by LC-MS, which indicates that MLB is almost degraded to small molecules. [ABSTRACT FROM AUTHOR]

Metal‐organic cages (MOCs) that assemble from metal ions or metal clusters and organic ligands have attracted the interest of the scientific community because of their various functional coordination cavities. Unlike metal‐organic frameworks (MOFs) with infinite frameworks, MOCs have discrete structures, making them soluble and stable in certain solvents and facilitating their application as starting reagents in the further construction of single components or composite materials. In recent years, increasing progress has been made in this field. In this review, we introduce these works from the perspective of design strategies, and focus on how presynthesized MOCs can be used to construct functional materials. Finally, we discuss the challenges and development prospects in this field. [ABSTRACT FROM AUTHOR]

Two amorphous metal–organic frameworks (aMOFs) were obtained from crystalline Co-MOF (SCNU-Z6) via temperature-induced (aT-SCNU-Z6) and water-immersed (aW-SCNU-Z6) approaches. They exhibited high iodine uptake, with the adsorption capacities of aT-SCNU-Z6 and aW-SCNU-Z6 reaching 2.05 and 5.04 g g−1, respectively. This work is the first report of iodine uptake by aMOFs. [ABSTRACT FROM AUTHOR]

Radioactive iodine is a major nuclear waste, and its capture and immobilization are highly desirable. Herein, a new Ni(II) metal–organic framework based on a newly designed imidazole–tetrazole heterotopic tripodal ligand, namely, SCNU-Z5, was constructed and applied to the capture of iodine from solution and the vapor phase. SCNU-Z5 has an interesting high-connectivity chiral framework with 1D helical channels. The combination of 1D channels and two other crossed 1D channels resulted in a porous framework with N,N-dimethylacetamide (DMAc) guest molecules. The guest molecules were exchanged by iodine molecules present in cyclohexane, water and vapor, with maximum adsorption capacities of 442, 352, and 1680 mg g−1, respectively. Mechanism studies showed that iodine adsorption was attributed to the charge transfer between iodine molecules and the framework and the interaction of iodine molecules themselves. Interestingly, the adsorption of iodine molecules led to amorphization of the framework, and I2 was buried and fixed stably inside the framework, thus providing a new strategy for stable immobilization of iodine in MOFs. [ABSTRACT FROM AUTHOR]

Since Fe(III) ions are of importance in biological systems, the development of new sensors for detecting Fe(III) with excellent selectivity and low detection limit is desirable. Herein, a new stable hydrazone-linked covalent organic framework (COF), namely, Tfpa–Mth COF, was synthesized by the Schiff-base condensation reaction between tris(4-formylphenyl) amine (Tfpa) and a chiral hydrazide precursor (Mth). The ethanol-dispersed Tfpa–Mth COF can be used as a fluorescence sensor for the detection of Fe(III) ions, showing high selectivity and low detection limit (64 nM). Moreover, a novel COF-based quartz crystal microbalance (QCM) sensor has been fabricated by the in situ growth of the Tfpa–Mth COF on an amino-modified QCM chip. Such a COF-based QCM sensor, with a uniform surface and thickness of the Tfpa–Mth COF film on the surface, is able to monitor Fe(III) ions in real-time with high selectivity. The recognition process, as a result of Fe(III) immobilization on the Tfpa–Mth COF framework, is further verified by zeta potential measurements and X-ray photoelectron spectroscopy. To the best of our knowledge, this represents the first report on the development of COF-based QCM sensors for metal ion detection. Exploration of the COF-based QCM sensor in our work demonstrates the new pathway for the selective detection of metal ions. [ABSTRACT FROM AUTHOR]

A metal–organic framework (MOF), namely SCNU-Z3, based on an imidazole-tetrazole tripodal ligand and Mn(II), has been constructed. It exhibits a porous 3D framework composed of truncated octahedron cage subunits. Unexpected ligand-induced missing metal-ion defects were observed in the framework. In addition, the application of SCNU-Z3 in a supercapacitor was performed. [ABSTRACT FROM AUTHOR]

The development of a robust and efficient stationary phase for chromatographic biopharmaceutical purification is of prime importance but remains challenging. Herein, we have developed a series of protein A-mesoporous silica composites for the first time by covalently coupling protein A with the tagged carbonyl imidazole moieties in the column, which constitutes a facile and efficient route for the preparation of protein A immunoaffinity materials. The resultant composites are employed as the stationary phase for chromatographic purification of immunoglobulin G (IgG). The effect of silica's pore size and coupled protein A on the antibody purification is systematically investigated. When the pore size of silica increased from 100 to 1000 Å, the amount of coupled protein A decreased, and the surface coverage on the silica significantly improved, accompanied by an increase in the amount of purified rabbit IgG. With an increasing coupled protein A, the surface coverage increased at first and decreased subsequently, which shows a similar trend to the amount of purified IgG and specific activity. When practically implemented for purifying several immunoglobulins that are central for commercial ELISA Kits, the protein A-mesoporous silica composite exhibited superior performance compared to the GE-Mabselcetxtra rProtein A column, particularly in the purification of immunoglobulin M (IgM), which cannot be realized by the GE-Mabselcetxtra rProtein A column. This study sheds new light on the rational development of protein-affinity chromatography for biopharmaceutical purification. [ABSTRACT FROM AUTHOR]

A new strategy of using a MOF as an effective amplifier in a QCM miRNA sensor was presented based on the selective interaction between a MOF (UiO-66) with different zeta potentials and different miRNAs. The signal can be significantly enhanced, which leads to significantly improved performance in miRNA detection. [ABSTRACT FROM AUTHOR]

The interaction between an aMOC and miRNA/DNA is studied and the use of a signal probe DNA (spDNA)@aMOC complex as an effective amplifier in a QCM sensor to detect miRNA is developed. The signal can be significantly enhanced, which leads to improved performance when detecting and distinguishing miRNAs. [ABSTRACT FROM AUTHOR]

A 2D imine-linked COF with a hitherto unreported htb type topology was synthesized from a linear diamine linker and a judiciously designed tetra-aldehyde building block. This work opens the door to the development of COFs with unprecedented topologies and may broaden the scope of COF functional materials by pore size and pore surface engineering. [ABSTRACT FROM AUTHOR]

Two new heterometallic coordination polymers, namely, [SmNa(μ2-HBIP)(μ3-HBIP)3]n (1) and {[TbAg2(μ3-HBIP)(μ3-BIP)(μ4-BIP)(H2O)]·4H2O}n (2), have been successfully synthesized under suitable conditions by selecting a N-heterocyclic carboxylic acid, 3-(1H-benzimidazol-2-yl)propanoic acid (H2BIP), as the multidentate ligand. Single-crystal X-ray diffraction studies indicate that both two compounds are one-dimensional (1D) heterometallic infinite chains, but showing distinctly different structural features. Compound 1 exhibits an interesting 1D heterometallic coordination chain constructed by the combination of two type of sub-chains [Sm(μ2-HBIP)] and [Na(μ3-HBIP)] with the μ3-HBIP− ligands. While compound 2 shows another 1D heterometallic chain built by the connection of discrete [Ag2(μ3-HBIP)(μ3-BIP)(μ4-BIP)] dinuclear units with Tb(III) centers. Moreover, various interactions, which are N–H···N hydrogen bonds and π...π stacking interactions, further link the 1D heterometallic chains into different 3D supramolecular frameworks of compounds 1 and 2, respectively. Additionally, the thermogravimetric analyses of both two compounds and the photoluminescent property of 2 have been investigated as well. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks are a new class of crystalline porous materials that have various potential applications. However, utilization of covalent organic frameworks as new stationary phases for gas chromatography separation has been less explored. In this work, a hydrazone‐linked chiral covalent organic framework has been covalently bonded onto the inner surface of fused silica capillary. The fabricated hydrazone‐linked covalent organic framework‐bound capillary column displays a moderate polarity nature and exhibits relatively high resolution performances for separation of linear alkanes and alcohols, as well as aromatic positional isomers including xylene, nitrotoluene, chloronitrobenzene, benzenediol, and naphthol isomers. The present study reveals that the hydrazone‐linked covalent organic framework‐bound capillary column is quite promising for the gas chromatography separation of aromatic positional isomers. [ABSTRACT FROM AUTHOR]

A new two-dimensional (2D) 3d-4f heterometallic coordination polymer, which is {[Tb2Zn4(µ3-TFMIDC)4(µ4-HTFMIDC)(H2O)8]·2H2O}n, has been successfully synthesized by the solvothermal reaction of 2-(trifluoromethyl)-1H-4,5-imidazole dicarboxylic acid (H3TFMIDC) with Zn(II) and Tb(III) ions. The title compound was structurally characterized by diverse characterization techniques including single-crystal X-ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Single-crystal structure analysis reveals that the as-preprared compound is a 2D heterometallic 3d-4f coordination network based on interesting planar tetranuclear squares [Zn4(TFMIDC)4] as building blocks, representing the first example of novel heterometallic coordination polymer based on the H3TFMIDC ligand. In addition, the title compound exhibits very intense green luminescence and characteristic transitions of the Tb(III) ion when excited at 291 nm. Lattice parameters for the title compound: a = 11.1449(12) Å, b = 12.8498(13) Å, c = 37.553(4) Å, α = β = γ = 90°, V = 5378.0(10) Å3, Z = 4.Graphical Abstract: A unique 2D 3d-4f heterometallic coordination polymer containing interesting planar tetranuclear square building blocks has been constructed by the solvothermal reaction of 2-(trifluoromethyl)-1H-4,5-imidazole dicarboxylic acid (H3TFMIDC) with Zn(II) and Tb(III) ions. [ABSTRACT FROM AUTHOR]

To explore the influence of in situ hydrolysis reaction on the assembly of coordination polymers (CPs), seven new CPs based on in situ formed 3,5-di(1H-1,2,4-triazol-1-yl)benzoic acid (HDTBA) from two different precursors, 3,5-di(1H-1,2,4-triazol-1-yl)benzonitrile (DTBN) and 5-(3,5-di(1H-1,2,4-triazol-1-yl)phenyl)-2H-tetrazole (HDTPT), were constructed. When DTBN is used as a precursor, four CPs, namely, [Zn(DTBA)2]n (1), [Cd(DTBA)2]n (2 and 3), and {[Cd(DTBA)2]·H2O}n (4), were obtained under hydrothermal conditions. Compound 1 is a nested double layer structure based on (6,3) networks. Compounds 2 and 3 are supramolecular isomers which were synthesized from Cd(NO3)2·6H2O and Cd(ClO4)2·6H2O, respectively. Compound 2 displays a 3D framework with a two-folded interpenetrating bimodal (3,6)-connected rtl network topology, while compound 3 possesses a 2D network with a CdI2-type network topology. Compound 4 presents a 3D framework that can be denoted as a new (3,5)-connected topological net with point symbol of {4·6·8}{4·64·85}. When HDTPT was used as a precursor under similar conditions, three CPs, namely, Zn(DTBA)NO3]n (5), [Zn(DTBA)Cl]n (6) and {[Cd(DTBA)(NO3)(H2O)]·H2O}n (7), were obtained. Compound 5 is a 2D network with a (4·82) topology, while compounds 6–7 are 2D networks with the same (6,3) network topology. Interestingly, anion…π interaction between inorganic anions and triazolyl ring can be observed and plays an important role in connecting the 2D layer into 3D supramolecular frameworks in 5–7. The results show that the in situ hydrolysis reactions affect the assembly processes significantly. The in situ reactions regulate the structure via changing the concentration (but not the total amount) of HDTBA during the assembly process, which in turn regulates the coordination competition between HDTBA and inorganic anions, thus generating different structures. Furthermore, their solid-state fluorescent properties were investigated at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: A new 3D Zn(II) MOF based on 2-(hydroxymethyl)-1H-imidazole-4,5-dicarboxylic acid (H4hmIDC), formulated as {[Zn3(HhmIDC)2(H2O)2]·2H2O}n, has been successfully prepared under hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction, elemental analysis and infrared spectroscopy, as well as power X-ray diffraction. It is worth noting that the unique HhmIDC3− ligand in the title compound adopts an unusual coordination mode, namely µ4-kN,O: kN′,O′: kO″,O‴: kO′′′′ to link the Zn(II) ions into an interesting 3D coordination framework. Such a 3D network can be further simplified as a binodal 4-connected mog (moganite) topology with the Schläfli symbol of (4·64·8)2(42·62·82). Moreover, the title Zn(II) MOF shows a relatively high thermal stability up to 340 °C, and exhibits an intense blue emission centered at 450 nm upon excitation at 370 nm.Graphical Abstract: A new 3D microporous Zn(II) MOF with an uncommon binodal 4-connected mog topology has been constructed from 2-(hydroxymethyl)-1H-imidazole-4,5-dicarboxylic acid (H4hmIDC). Such a Zn(II) MOF displays a relatively high thermal stability and exhibits very strong blue photoluminescence with a maximum emission band at 450 nm when excited at 370 nm. [ABSTRACT FROM AUTHOR]

Two new imidazole-based dicarboxylate ligands, which are 2-(pyridin-4-ylmethyl)-1H-imidazole-4,5-dicarboxylic acid (H3pPyMIDC) and 2-(pyridin-3-ylmethyl)-1H-imidazole-4,5-dicarboxylic acid (H3mPyMIDC), have been designed and successfully synthesized. Both these multidentate ligands are then used to react with different kinds of alkaline earth metal ions under solvothermal conditions, leading to the construction of a series of new coordination polymers (CPs), namely, [Ba(μ5-HpPyMIDC)(H2O)]n (1), [Sr(μ5-HpPyMIDC)(H2O)]n (2), [Ca2(μ4-HpPyMIDC)2(H2O)2]n (3), {[Ca2(μ3-HpPyMIDC)(μ4-HpPyMIDC)(H2O)2]·H2O}n (4), [Ba(μ5-HmPyMIDC)(H2O)]n (5), {[Mg10(μ3-mPyMIDC)3(μ4-mPyMIDC)3(H2O)21]·SO4·12H2O}n (6) and {[Sr(μ2-H2mPyMIDC)2(DMF)2]n·H2O}n (7). Compounds 1 and 2 are isostructural, exhibiting two-dimensional (2D) network structures with a hexagonal honeycomb (6,3) topology if the corresponding metal ions are seen as 3-connected nodes. Compound 3 displays another type of 2D network, which is built by the connection of μ4-HpPyMIDC ligands and Ca(ii) centres. Compound 4 is a binodal (3,4)-connected 3D framework with the Schläfli symbol of (6·82)(65·8). The 2D structure of compound 5 is similar to those of compounds 1 and 2, although different kinds of ligands are employed. Compound 6 exhibits an interesting 3D framework with a pcu topology by considering each unusual heptanuclear magnesium cluster as a 6-connected node. In compound 7, connection of μ2-H2mPyMIDC ligands with Sr(ii) ions results in the formation of an uncommon 3D chiral framework containing two different types of 1D helical chains. The present results reveal that both these new imidazole-based dicarboxylate ligands containing flexible pyridinylmethyl groups show versatile coordination abilities and are good candidates for fabricating new CPs. Moreover, the thermogravimetric and solid-state luminescence properties of all the compounds have also been studied. [ABSTRACT FROM AUTHOR]

Two new imidazole-based dicarboxylate ligands, which are 2-(pyridin-4-ylmethyl)-1H-imidazole-4,5-dicarboxylic acid (H3pPyMIDC) and 2-(pyridin-3-ylmethyl)-1H-imidazole-4,5-dicarboxylic acid (H3mPyMIDC), have been designed and successfully synthesized. Both these multidentate ligands are then used to react with different kinds of alkaline earth metal ions under solvothermal conditions, leading to the construction of a series of new coordination polymers (CPs), namely, [Ba(μ5-HpPyMIDC)(H2O)]n (1), [Sr(μ5-HpPyMIDC)(H2O)]n (2), [Ca2(μ4-HpPyMIDC)2(H2O)2]n (3), {[Ca2(μ3-HpPyMIDC)(μ4-HpPyMIDC)(H2O)2]·H2O}n (4), [Ba(μ5-HmPyMIDC)(H2O)]n (5), {[Mg10(μ3-mPyMIDC)3(μ4-mPyMIDC)3(H2O)21]·SO4·12H2O}n (6) and {[Sr(μ2-H2mPyMIDC)2(DMF)2]n·H2O}n (7). Compounds 1 and 2 are isostructural, exhibiting two-dimensional (2D) network structures with a hexagonal honeycomb (6,3) topology if the corresponding metal ions are seen as 3-connected nodes. Compound 3 displays another type of 2D network, which is built by the connection of μ4-HpPyMIDC ligands and Ca(ii) centres. Compound 4 is a binodal (3,4)-connected 3D framework with the Schläfli symbol of (6·82)(65·8). The 2D structure of compound 5 is similar to those of compounds 1 and 2, although different kinds of ligands are employed. Compound 6 exhibits an interesting 3D framework with a pcu topology by considering each unusual heptanuclear magnesium cluster as a 6-connected node. In compound 7, connection of μ2-H2mPyMIDC ligands with Sr(ii) ions results in the formation of an uncommon 3D chiral framework containing two different types of 1D helical chains. The present results reveal that both these new imidazole-based dicarboxylate ligands containing flexible pyridinylmethyl groups show versatile coordination abilities and are good candidates for fabricating new CPs. Moreover, the thermogravimetric and solid-state luminescence properties of all the compounds have also been studied. [ABSTRACT FROM AUTHOR]

A series of new two-dimensional (2D) lanthanide(III) coordination polymers, namely {[Ln( μ -HTFMIDC)(DMA)] · 2HO} [Ln = Pr ( 1); Nd ( 2); Sm ( 3); Eu ( 4); HTFMIDC = 2-(trifluoromethyl)-1 H-imidazole-4,5-dicarboxylic acid, DMA = N, N′-dimethylacetamide] for type I and {[Ln( μ -HTFMIDC)(DMA)(HO)] · DMA} [Ln = Eu ( 5); Gd ( 6)] for type II, have been successfully prepared under solvothermal conditions and structurally characterized for the first time. Both two types of structures exhibit similar 2D honeycomb-like networks, which are constructed by the linkages of μ -HTFMIDC bis-(bidentate) bridging ligands and Ln(III) metal centers. However, slightly different ABAB stacking fashions of the 2D layers and distinctly different hydrogen bonding interactions between the neighboring 2D layers are observed in crystal structures of type I and type II, which may be attributed to the lanthanide contraction effect. Meanwhile, the solid-state luminescent properties of 4 and 5 have been also investigated. [ABSTRACT FROM AUTHOR]

The imidazole-based dicarboxylate ligand 2-(4-(pyridin-4-yl)phenyl)-1H-imidazole-4,5-dicarboxylic acid (H3PyPhIDC), was synthesized and its coordination chemistry was studied. Solvothermal reactions of CaII, MnII, CoII, and NiII ions with H3PyPhIDC produced four coordination polymers, [Ca(µ3-HPyPhIDC)(H2O)2]n (1), {[M3(µ2- H2PyPhIDC)2(µ3-HPyPhIDC)26(H2O)2]·6H2O}n [M = Mn (2), Co (3)], and {[Ni(µ3-HPyPhIDC)(H2O)]·H2O}n (4). Compounds 1-4 were analyzed by IR spectroscopy, elemental analyses, and single-crystal and powder X-ray diffraction. Compound 1 displays a one-dimensional (1D) infinite chain. Compounds 2 and 3 are of similar structure, showing 2D network structures with a (4,4) topology based on trinuclear clusters. Compound 4 has another type of 2D network structure with a 3-connected (4.8²) topology. The results revealed that the structural diversity is attributed to the coordination numbers and geometries of metal ions as well as the coordination modes and conformations of H3PyPhIDC. Moreover, the thermogravimetric analyses of all the compounds as well as luminescence properties of the H3PyPhIDC ligand and compound 1 were also studied. [ABSTRACT FROM AUTHOR]

Three coordination polymers, {[CdI(DBBA)]∙0.5H2O}n(1, DBBA = 3,5-di(1Hbenzo[d]imidazol-1-yl)benzoate), [Cd(DBBA)(CH3COO)]n(2) and [Cd(DBBA)2]n(3), were obtained through reactions between Cd(II) salts and 3,5-di(1H-benzo[d]imidazol-1-yl)benzoic acid under different pH conditions. Compounds1and2are 3-D frameworks withrtltopology based on different binuclear Cd(II) secondary building units. Compound3was formed at lower pH and showed a 1-D chain assembled with M2L2ring units. Moreover, phase purities, thermal behaviors, and photoluminescent properties have also been investigated. [ABSTRACT FROM AUTHOR]

Six new d–f heterometallic Ln(iii)–Zn(ii) coordination polymers (CPs), namely, {[EuZn(NIPH)1.5(INC)(H2O)(OH)]·0.5H2O}n (1), [LnZn(NIPH)2(INC)(H2O)]n [Ln = Eu (2), Tb (3)], [EuZn2(NIPH)2.5(INC)2]n (4) and [LnZn(NIPH)2(NC)(H2O)]n [Ln = Eu (5), Tb (6)] [H2NIPH = 5-nitroisophthalate, HINC = isonicotinate, and HNC = nicotinate], were obtained under hydrothermal conditions. All the compounds are based on well-defined heterometallic secondary building units (SBUs). Compound 1 is a 3D network with pcu topology, which was generated from tetragonal tetranuclear heterometallic [Eu2Zn2(NIPH)4(INC)2(OH)2] SBUs connected by NIPH2− and INC− ligands. Compounds 2 and 3 are isostructural and exhibit 3D heterometallic frameworks with bcu topology constructed by the linkage of 2D layers containing linear tetranuclear heterometallic [Eu2Zn2(NIPH)6(INC)2] SBUs and INC− anions. Compound 4 possesses 7-connected 3D frameworks with the Schläfli symbol of (33·411·56·6) constructed by the interconnection of linear trinuclear heterometallic [EuZn2(NIPH)4(INC)4] SBUs, NIPH2− ligands and INC− anions. In compounds 5 and 6, 3D networks are formed through the linkage among linear tetranuclear [Ln2Zn2(NIPH)8(NC)2] SBUs, NIPH2− ligands and NC− anions. All the compounds represent examples of 3D lanthanide–transition heterometallic–organic coordination polymers with two types of metal ions and two organic carboxylates. Furthermore, their solid-state fluorescence properties have been investigated at room temperature. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of 2,3,5,6-tetra(2-pyridyl)pyrazine (tppz) and sodium azide with different cadmium salts including CdCl2·2.5H2O, Cd(NO3)2 and Cd(CH3COO)2·2H2O at 80 °C produce three new coordination polymers, namely, {[Cd2(N3)2(tppz)Cl2]·2H2O}n (1), [Cd2(N3)2(tppz)(NO3)2]n (2) and {[Cd2(N3)2(tppz)(CH3COO)2]·2H2O}n (3), respectively. Single-crystal X-ray diffraction analysis reveals that the anions of the Cd(ii) salts all participate in coordination in compounds 1–3. Compound 1 features an infinite one-dimensional (1D) chain with loops-and-rods topology, compound 2 exhibits a 1D ladder-like chain, while compound 3 possesses a 2D honeycomb-like network structure with (6,3) topology. The low-dimensional structures of compounds 1–3 are further stabilized by diverse supramolecular interactions such as hydrogen bonds and π…π stacking. Interestingly, when the temperature is increased to 100 °C, similar reactions of tppz and sodium azide ligands with CdCl2·2.5H2O, Cd(NO3)2 and Cd(CH3COO)2·2H2O lead to three other novel 3D Cd(ii) coordination polymers formulated as [Cd3(N3)6(tppz)]n (4), {[Cd2(N3)2(tppz)(NO3)2]·MeOH}n (5) and [Cd4(N3)6(tppz)(CH3COO)2]n (6), respectively. The anions of the Cd(ii) salts again take part in coordination in compounds 5 and 6 but disappear in the final structure of 4. Compound 4 displays a rare sxd-type 3D framework with the Schläfli symbol of (33·46·55·6) if each V-shaped trinuclear [Cd3(μ1,1-N3)4] secondary building unit (SBU) is regarded as a 6-connected node. In compound 5, both the Cd1 and Cd2 atoms serve as 3-connected nodes to construct an uncommon binodal (3,3)-connected 3D framework with (6·102)(62·10) topology. Compound 6 contains another type of V-shaped trinuclear [Cd3(μ1,1-N3)2(μ3-CH3COO)] SBU, which acts as a 7-connected node to fabricate a unique uninodal 7-connected 3D framework with a completely new topology of (36·42·510·63). The present results reveal that both anions and temperature play essential roles in the structural and topological diversity of such six new Cd(ii) coordination polymers. Moreover, the IR spectra, thermogravimetric analysis curves, and solid-state luminescence properties of all the compounds have been also investigated. Compared with the free tppz ligand, compounds 1–6 exhibit superior luminescence properties with largely enhanced emission, indicating that they may be good candidates for optical materials. [ABSTRACT FROM AUTHOR]

Four coordination polymers based on 4′-(2H-tetrazol-5-yl)biphenyl-4-carboxylic acid (H2TBPC), [Zn(μ3-TBPC)(H2O)]n(1), [Zn(μ3-TBPC)(Me2NH)]n(2), [Cd(μ3-TBPC)(bpy)]n(bpy = 4,4′-bipyridine,3), and [Cd(μ4-TBPC)(H2O)]n(4), were constructed under hydrothermal conditions. The compounds are composed of M2(TBPC)2binuclear ring as a building block. In1–3, the binuclear rings are interconnected to three different 2-D networks with the same (4·82) topology. In4, the binuclear rings are arranged into a 3-D framework with PtS-type topology. The results revealed that the structural diversity is mainly attributed to the coordination geometries of metal ion, the coordination modes of TBPC2−, and the auxiliary ligand. The thermal stabilities and luminescent properties of1–4have also been studied. [ABSTRACT FROM PUBLISHER]

Four new coordination polymers, [Cd(3-TPTP)Cl]2(3-HTPTP = 4′-(3-tetrazolylphenyl)2,2′:6′2′′-terpyridine,1),{[Cd(3-TPTP)(pBDC)0.5]∙4H2O}n(pH2BDC = 1,4-benzenedicarboxylic acid,2), {[Mn(3-TPTP)(mBDC)0.5]∙5H2O}n(mH2BDC = 1,3-benzenedicarboxylic acid,3), and [Pb(3-TPTP)(H2O)2]∙OH (4), were obtained. Compounds1–3are composed of binuclear [M2(3-TPTP)2] ring as building unit. In1, the binuclear rings pack into a 3-D supramolecular framework via various hydrogen bonds. In2and3, the binuclear rings are connected bymBDC2−andpBDC2−, respectively, resulting in two types of 1-D chains. In4, the mononuclear [Pb(3-TPTP)] units are connected by Pb⋯N weak interactions, giving a chiral 1-D coordination chain, which is further connected by O–H⋯N interaction to form a chiral 3-D supramolecular framework. The phase purity of1–4and luminescence properties of1,2, and4were also investigated. [ABSTRACT FROM PUBLISHER]

Solvothermal reactions of Co2+ and Mn2+ salts with 2-(trifluoromethyl)-1H-4,5-imidazole dicarboxylic acid (H3TFMIDC) lead to two novel three-dimensional (3D) metal–organic frameworks (MOFs), namely, [Co6(μ3-TFMIDC)4(H2O)12]·15H2O (1) and [(Me2NH2)3][MnII6 MnIII(μ3-TFMIDC)6(H2O)6]·18H2O (2). Single-crystal X-ray diffraction analysis reveals that both of them are based on interesting planar tetranuclear squares [M4(TFMIDC)4] as secondary building units (SBUs). Compound 1 exhibits a unique 3D two-fold interpenetrated network with the diamondoid topology consisting of the tetranuclear square SBUs as 4-connected nodes, while compound 2 features an unusual (6,16)-connected 3D framework based on the novel tetranuclear square SBUs as 16-connected nodes and trivalent manganese ions as 6-connected nodes, representing the first 16-connected MOF utilizing planar tetranuclear square SBUs as building blocks. Our results open up new perspectives to design novel 3D extended MOFs, especially the unique highly connected 3D MOFs by employing planar tetranuclear square SBUs. Moreover, IR spectroscopy, powder X-ray diffraction, thermogravimetric analyses, and a study on the magnetic properties of both compounds, have been also performed. [ABSTRACT FROM AUTHOR]

Two main group coordination polymers based on 2-(2-pyridyl)-4,5-imidazole-dicarboxylic acid (H3oPyIDC), namely [Ba(H2oPyIDC)2(H2O)]n (1) and [Pb2(HoPyIDC)2]n (2) are obtained under hydrothermal conditions. In compound 1, the Ba2+ cations and HoPyIDC2- anions are connected to a 1D chain, and the 1D chains are further interconnected by Ba-O bonds, forming a 3D 3-connected framework. In compound 2, a 2D layer with (4,4) topology is formed by PbII ions and HoPyIDC2- anions. The 2D layer are pillared by HoPyIDC2-, yielding a 3D (3,4)-connected framework. The thermogravimetric analyses and luminescence properties of compounds 1 and 2 are also investigated. [ABSTRACT FROM AUTHOR]

Three coordination polymers based on different organic ligands, namely [Cu(bbn)Cl] (bbn = 4-(1H-benzimidazol-1-yl)benzonitrile, 1), [Zn(tpb)] (Htpb = 1-(4-(2H-tetrazol-5-yl)phenyl)-1H-benzimidazole, 2), and [Cd(bba)(HO)] (Hbba = 4-(1H-benzimidazol-1-yl)benzoic acid, 3), were constructed from the same precursor, bbn. The bbn precursor remains unchanged in complex 1 but undergoes in situ reactions to give complexes 2 and 3 under different experimental conditions. Complex 1 is a 1D chain based on [CuCl] chains and bbn ligands. Complex 2 has a 1D chain composed of [Zn(tpb)] subunits and tpb linkers. Complex 3 displays a twofold interpenetrating framework with dia topology. The results showed that the generation of different organic ligands from the same precursor via in situ reactions is a simple method for obtaining coordination polymer with diverse structures. The thermal stabilities and luminescent properties of selected compounds have been studied. [ABSTRACT FROM AUTHOR]

Nine new coordination compounds, namely, {[Zn(HDSPTP)2(H2O)4]·6H2O}n (H2DSPTP = 4′-(2,4-disulfophenyl)-4,2′:6′,4′′-terpyridine, (1), [Cd(DSPTP)(H2O)2]n (2), {[Ag(HDSPTP)]·30H2O}n (3), {[Ag(HDSPTP)(H2O)]·3H2O}n (4), [Ag2(DSPTP)]n (5), {[Ag4(DSPTP)2(H2O)3]·2H2O}n (6), [Pb(DSPTP)(H2O)2]n (7), {[Pb(DSPTP)(H2O)3]·3H2O}n (8), and [PbK(DSPTP)(NO3)(H2O)2]·H2O}n (9), were synthesized by introducing a ligand with both terpyridyl and sulfo groups as organic linkers. The reaction of H2DSPTP with Zn(ii) salts only resulted in a mononuclear complex (compound 1), in which most donor groups appear uncoordinated, whereas the reaction with Cd(ii) salts under similar conditions resulted in a three-dimensional (3D) twofold interpenetrated dia framework (compound 2). The reactions of H2DSPTP with AgCF3CO2 or AgNO3 resulted in compounds 3–6 with different structures: a porous supramolecular framework via interlaced packing of one-dimensional (1D) coordination chains (compound 3), a two-dimensional (6,3) network based on coordination bonds and Ag…O interactions (compound 4), a 3D framework based on 1D [Ag2(2-SO3−)2]n secondary building blocks (compound 5), and a twofold interpenetrated framework with a binodal (4,6)-connected fsh topology based on planar tetranuclear SBUs as nodes (compound 6). The reactions of H2DSPTP with Pb(NO3)2 resulted in the following three compounds: a 3D twofold interpenetrated dia framework (complex 7), a twofold interpenetrated (6,3) network (compound 8), and a 3D complicated framework based on tetranuclear SBUs, double-bridge DSPTP2− ligands, and [K(H2O)]+ species (compound 9). The structural diversity is mainly attributed to the rich coordination behaviors of the HDSPTP−/DSPTP2− ligands and the metal center and can be controllably synthesized by altering the metal to ligand ratio, added alkali, and the pH value for the Ag(i) and Pb(ii) compounds. Compound 2 exhibits a high thermal stability above 500 °C, undergoes a crystalline–amorphous–crystalline phase transition as temperature is increased from 25 °C to 500 °C, and shows an amorphous–crystalline phase transition when rehydrated. Moreover, the luminescence properties of all the compounds were also investigated. [ABSTRACT FROM AUTHOR]

The reactions of Cd(ii) salts and 5-(3-(1H-imidazol-1-yl)phenyl)-1H-tetrazolate (3-HIPT) resulted in eight new coordination polymers (CPs), namely, {[Cd(3-IPT)2(H2O)2]·H2O}n (1 and 2), {[Cd(3-IPT)2(H2O)2]·2H2O}n (3), [Cd(3-IPT)(H2O)Cl]n (4), [Cd(3-IPT)Cl]n (5), [Cd(3-HIPT)I2]n (6), [Cd(3-IPT)I]n (7), and [Cd(3-HIPT)2]n (8). Single-crystal X-ray analysis revealed that compound 1 is a 1D beaded chain, whereas compounds 2 and 3 are made of 2D networks. Compounds 1–3 are supramolecular isomers; their synthesis can be controlled under different temperatures and concentrations. The results showed that compounds 1 and 3 are the most thermodynamically and kinetically favored products, respectively. The thermodynamic stability of compound 1 may be attributed to the formation of the smallest M2L2 ring in the compound. Compounds 4–7 were obtained at higher Cl−/I− concentrations. Compound 4 is a 2D net composed of 1D [Cd(3-IPT)]n chains and μ2-Cl and μ2-H2O connectors. Compound 5 is a (3,6)-connected 3D framework with rtl topology. Compound 6 possesses a 1D chain with 3-HIPT ligands on both sides. Compound 7 is a 2D (4·82) net. Compound 8, a 3D pcu framework based on trinuclear linear SBUs, was formed when Cd(CF3CO2)2 was introduced at 170 °C. Based on a temperature-changing cycle, compounds 1 and 3 display crystal-to-amorphous-to-crystal phase transitions accompanying the dehydration–rehydration process, whereas compound 2 only displays crystal-to-amorphous phase transition when the temperature is increased and cannot go back to the crystal phase again. Interestingly, solvent-mediated structural transformations were accomplished among the selected compounds. When compounds 2, 3, 6, 7, or 8 were left in a water and NaCl solution at 170 °C, they were partly/fully transformed into compounds 1 and 5, respectively. When compound 5 was recrystallized in water at 120 and 170 °C, it was partly and fully transformed into compounds 2 and 1, respectively. Such transformations were induced by the temperature or an anion. In addition, the thermal stabilities and luminescence properties of selected compounds have also been studied in detail. The complexes exhibit intense solid-state fluorescence emission at room temperature. [ABSTRACT FROM AUTHOR]

Two coordination polymers (CPs), namely, [Cu(Hptz)2(Hhba)2] n ( 1) [Hptz = 5-(4-pyridyl)-1H-tetrazole, H2hba = 2-hydroxybenzoic acid] and [Zn3(ptz)2(hpa)2] n ( 2) (H2hpa = 2-hydroxy-2-phenylacetic acid), were synthesized by solvothermal reactions. Both complexes were characterized by elemental analysis, infrared spectroscopy, powder X-ray diffraction, thermogravimetric analysis, and single-crystal X-ray diffraction analysis. Compound 1 exhibits a 2D (4,4) network, where each layer connects to four adjacent layers to construct a 3D supramolecular framework. Compound 2 has a 3D framework structure composed of 1D SUBs, which are formed by both carboxyl and tetrazole groups. The complexes represent two rare examples of CPs constructed from Hptz and organic carboxyl acid ligands. Complex 2 exhibits intense, red-shifted emissions in the visible region at room temperature. [ABSTRACT FROM AUTHOR]

A new cyclodextrin-derived chiral stationary phase (denoted as CDA-CSP) was synthesized by immobilizing mono(6A-azido-6A-deoxy)-per(p-chlorophenyl carbamoylated) β-cyclodextrin derivative to alkynyl modified silica via click chemistry. This newly prepared CSP shows good enantioseparation performance for six chiral compounds (1–6), such as 4-phenyl-oxazolidine-2-thione, two kinds of aryl alcohols, substituted flavonoids and benzoin, in which baseline separation of Analytes 1–4 was achieved under the experimental conditions. The effects of column temperature, mobile phase pH and content of methanol on the enantioseparation characteristics of CDA-CSP were investigated in detail. Retention factor and resolution for Compound 3 gradually reduced with an increase of column temperature, and a good linear relationship was shown between napierian logarithm of selectivity factor and reciprocal of column temperature. In the pH range from 3.56 to 5.50, a change in pH hardly affected the resolution of Analyte 2. In addition, increasing methanol in the mobile phase resulted in rapid eluting of the analytes from the column in reversed-phase mode. The retention factors for Analytes 1 and 3 significantly decreased and their resolution showed different trends. [ABSTRACT FROM AUTHOR]

ABSTRACT Twelve chiral compounds were enantiomerically resolved on bovine serum albumin chiral stationary phase (BSA-CSP) by high-performance (HPLC) in reversed-phase modes. Chromatographic conditions such as mobile phase pH, the percentage of organic modifier, and concentration of analyte were optimized for separation of enantiomers. For N-(2, 4-dinitrophenyl)-serine (DNP-ser), the factors ( k) greatly increase from 0.81 to 6.23 as the pH decreasing from 7.21 to 5.14, and the resolution factor ( Rs) exhibited a similar increasing trend (from 0 to 1.34). More interestingly, the factors for N-(2, 4-dinitrophenyl)-proline (DNP-pro) decrease along with increasing 1-propanol in mobile phase (3%, 5%, 7% and 9% by volume), whereas the resolution factor shows an upward trend (from 0.96 to 2.04). Moreover, mechanisms for chiral analytes were further investigated through thermodynamic methods. Chirality 25:487-492, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Two lanthanide coordination polymers, [Tm2·(5-IPA)4·(2,2′-Hbipy)2]·3H2O (1, 5-H2IPA = 5-hydroxyisophthalic acid, 2,2′-bipy = 2,2′-bipyridine) and [Er·(5-HIPA)3·(4,4′-bipy)3·(H2O)2]·3H2O (2, 4,4′-bipy = 4,4′-bipyridine), have formed by hydrothermal synthesis. Complex1exhibits a 2-D coordination network containing parallelepiped-shaped voids occupied by guest 2′2-bipy molecules. Complex2possesses a 1-D linear chain structure. The 1-D chains are linked by 4,4′-bipy molecules to form a 3-D supramolecular framework. IR spectroscopy, elemental analysis, and thermogravimetric analysis were also investigated. [ABSTRACT FROM AUTHOR]

The reaction of a new ligand, N,N′-(5,7-dihydro-1,3,5,7-tetraoxobenzo[1,2-c:4,5-c′]dipyrrole-2,6(1H,3H)-diyl)bis-(9CI)-3-pyrazinecarboxamide (L), with CuCl2·2H2O, CuI, or Cu(ClO4)·2H2O yields five coordination polymers. Among these polymers are three new coordination polymers, [CuII2(μ3-pzc)2(μ1-Cl)2]n (1), [CuICuII(μ2-pzc)2(μ2-Cl)(H2O)]n (2a), and {[CuI2CuII(μ2-pzc)2(μ3-I)2(H2O)]·H2O}n (3), as well as two previously reported coordination compounds, [CuICuII(μ2-pzc)2(μ2-Cl)(H2O)]n (2b) and [CuII(pzc)2] (4), in which 2-pyrazinecarboxylate (Hpzc) was obtained from in situ hydrolysis of the L ligand. Compound 1 is a two-dimensional (2D) double-layer structure, which can be viewed as a binodal (3,3)-connected network with the Schläfli symbol of (62·10) (6·102). Compounds 2a and 2b are two supramolecular isomers, both of them are (4,4) nets in topological view but showing different packing modes. Compound 3 has a 3D open framework constructed from the linkages of 1D sawtooth chains of iodide copper(i) clusters with [CuII(μ2-pzc)] subunits. Compound 4 is a mononuclear complex. Interestingly, except for compounds 2b and 4, all the other compounds cannot be directly synthesized using Hpzc and the corresponding Cu ions as initial reactants under the same reaction conditions. This finding indicates that the structural diversity of this system is tuned by the in situ hydrolysis reactions. [ABSTRACT FROM AUTHOR]

ABSTRACT Quartz crystal microbalance (QCM) biosensor was used for the chiral recognition of five pairs of enantiomers by using goat serum albumin (GSA) and rabbit serum albumin (RbSA) as chiral selectors. Serum albumin (SA) was immobilized on the QCM through the self-assembled monolayer technique, and the surface concentration of GSA and RbSA were 8.8 × 10−12 mol cm−2 and 1.2 × 10−11 mol cm−2, respectively. The QCM biosensors showed excellent sensitivity and selectivity. Meanwhile, the chiral recognition of SA sensors was quite species dependent. There were differences between GSA and RbSA sensors in the ability and the preference of chiral recognition. To R, S-1,2,3,4-tetrahydro-1-naphthylamine ( R, S-1-TNA), R, S-1-(4-methoxyphenyl)ethylamine ( R, S-4-MPEA), and R, S-1-(3-methoxyphenyl)ethylamine ( R, S-3-MPEA), the preference of the stereoselective SA-drug binding of the two kinds of SA sensors were consistent. However, to R, S-2-octanol ( R, S-2-OT) and R, S-methyl lactate ( R, S-MEL), the two kinds of SA sensors had opposite chiral recognition preference. Moreover, the interactions of SA and the five pairs of enantiomers have been further investigated through ultraviolet (UV) and fluorescent (FL) spectra. The UV/FL results were in accordance with the consequence of QCM. Chirality 24:804-809, 2012. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The title compound, poly[aqua(μ2-1 H-imidazole-4-carboxylato-κ3 N3, O: O′)hemi(μ2-oxalato-κ4 O1, O2: O1′, O2′)cadmium(II)], [Cd(C4H3N2O2)(C2O4)0.5(H2O)] n, exhibits a two-dimensional network. The CdII cation is coordinated to one N atom and two carboxylate O atoms from two 1 H-imidazole-4-carboxylate (Himc) ligands, two carboxylate O atoms from the bridging oxalate anion and one ligated water molecule; these six donor atoms form a distorted octahedral configuration. The oxalate anion lies on a centre of inversion. The Himc ligands connect the CdII cations to form -Cd-Himc-Cd-Himc-Cd- zigzag chains, with a Cd...Cd separation of 5.8206 (6) Å along the b direction, which are further linked by tetradentate oxalate anions to generate a two-dimensional herringbone architecture in the ab plane. These layers are extended to form a three-dimensional supramolecular framework via O-H...O and N-H...O hydrogen bonds and π-π stacking interactions. The solid-state photoluminscent behaviour of the title compound has been investigated at room temperature. [ABSTRACT FROM AUTHOR]

The chiral selector 6-azido-2, 3-di(p-chlorophenylcarbamoylated) cellulose was synthesized and further chemically immobilized onto 5-μm amino functionalized spherical porous silica gel. It was used as chiral stationary phase in high-performance liquid chromatography. Thirty racemates were successfully separated into enantiomers in either normal phase mode or reversed-phase mode. Good reproducibility and stability of the chiral stationary phase have been demonstrated. [ABSTRACT FROM PUBLISHER]

The title compounds, trans-bis(1 H-benzimidazole-2-carboxylato-κ2 N3, O)bis(ethanol-κ O)cadmium(II), [Cd(C8H5N2O2)2(C2H6O)2], (I), and trans-bis(1 H-benzimidazole-κ N3)bis(1 H-benzimidazole-2-carboxylato-κ2 N3, O)nickel(II), [Ni(C8H5N2O2)2(C7H6N2)2], (II), are hydrogen-bonded supramolecular complexes. In (I), the CdII ion is six-coordinated by two O atoms from two ethanol molecules, and by two O and two N atoms from two bidentate benzimidazole-2-carboxylate (HBIC) ligands, giving a distorted octahedral geometry. The combination of O-H...O and N-H...O hydrogen bonds results in two-dimensional layers parallel to the ab plane. In (II), the six-coordinated NiII atom, which lies on an inversion centre, shows a similar distorted octahedral geometry to the CdII ion in (I); two benzimidazole molecules occupy the axial sites and the equatorial plane contains two chelating HBIC ligands. Pairs of N-H...O hydrogen bonds between pairs of HBIC anions connect adjacent NiII coordination units to form a one-dimensional chain parallel to the a axis. Moreover, these one-dimensional chains are further linked via N-H...O hydrogen bonds between HBIC anions and benzimidazole molecules to generate a three-dimensional supramolecular framework. The two compounds show quite different supramolecular networks, which may be explained by the fact that different co-ligands occupy the axial sites in the coordination units. [ABSTRACT FROM AUTHOR]

Two new lanthanide coordination polymers [Ln(noa)(HO)] [Ln = Pr ( 1) and Nd ( 2), noa = α-naphthoxyacetate] have been synthesized under hydrothermal conditions and characterized by X-ray crystallography, IR spectra, and thermal analysis. In the crystal structure, adjacent Ln(III) ions were connected each other by tridentate bridging noa anions to form a one-dimensional (1D) chain-like structure. Moreover, the 1D chains were further linked together via hydrogen bonds and π-π attractions, resulting in an extended two-dimensional (2D) supramolecular network. The noa ligands adopted two different coordination modes, namely, chelating and tridentate bridging. [ABSTRACT FROM AUTHOR]

Nine 3D heterometallic coordination polymers, namely [NaLn2Cu6I5(IN)6(ox)(H2O)4]·H2O [Ln = La (1), Eu (2), Gd (3), Tb (4), HIN = isonicotinic acid, ox = oxalate], [Ln2Ag4(IN)5(ox)2(NO3)(H2O)2]·3H2O [Ln = Dy (5), (6) Ho], [LnAg(IN)2(ox)]·H2O [Ln = La (7), Pr (8), Tm (9)] have been successfully synthesized under hydrothermal conditions. Compounds 1–4exhibit same unusual 3D pillared-layer heterometallic coordination frameworks that are built up by the Ln-ox-Na layers, 2D inorganic [(Cu6I5)+]nlayers and IN ligands. Compounds 5and 6represent 3D coordination frameworks that are constructed from rare Ln(III)-ox-IN chains and Ag(i)-IN-ox layers. 3D coordination networks of compounds 7–9are built up from 2D Ln(iii)-IN-ox layers and Ag(i)-IN-ox subunits. Furthermore, the magnetic properties of compounds 5and 6and the luminescence properties of compounds 2, 4and 5have been investigated. [ABSTRACT FROM AUTHOR]