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The article determines the hydrogen bond-directed supramolecular arrays in 4,4'-bipyridinium tetrachloroterepththalate dihydrate and bis(1,10-phenanthrolinium) tetrachloroterephthalate tetrachloroterephthalic acid trihydrate. It describes the bonds between carboxylate and pyridinium groups and the crystallization of tetrachloroterephthalic acid with phenanthroline. Also observed are the dihedral angles between the carboxylate/carboxyl groups and tetrachlorinated aromatic rings and the intermolecular link of the packing's neutral and dianionic moieties.

The synthesis of cyclic carbonates through cycloaddition reactions between epoxides and carbon dioxide (CO2) is an important industrial process. Metal-Organic Frameworks (MOFs) have functional and ordered pore structures, making them attractive catalysts for converting gas molecules into valuable products. One approach to enhance the catalytic activity of MOFs in CO2 cycloaddition reactions is to create open metal sites within MOFs. In this study, the amino-functionalized rare earth Gd-MOF (Gd-TPTC-NH2) and its ionic liquid composite catalysts (Gd-TPTC-NH-[BMIM]Br) were synthesized using 2'-amino-[1,1':4',1"-terphenyl]-3,3",5,5"-tetracarboxylic acid (H4TPTC-NH2) as the ligand. The catalytic performance of these two catalysts was observed in the cycloaddition reaction of CO2 and epoxides. Under the optimized reaction conditions, Gd-TPTC-NH-[BMIM]Br can effectively catalyze the cycloaddition reaction of a variety of epoxide substrates with good to excellent yields of cyclic carbonate products. Comparatively, epichlorohydrin and epibromohydrin, which possess halogen substituents, promote higher yields of cyclic carbonates due to the electron-withdrawing nature of Cl and Br substituents. Additionally, the Gd-TPTC-NH- [BMIM]Br catalyst demonstrated good recyclability and reproducibility, maintaining its catalytic activity without any changes in its structure or properties after five reuse cycles. [ABSTRACT FROM AUTHOR]

In the centrosymmetric molecule of the title compound, C20H14F4N4O2, the pyridine ring is twisted with respect to the benzene ring with a dihedral angle of 66.85 (10)°. In the crystal structure, molecules are linked by intermolecular hydrogen- bonding and C—H…π interactions. [ABSTRACT FROM AUTHOR]

The article presents the structure and composition of the compound N-(4-Methoxy-6-methyl-1,3,5-triazin-2-yl)- N-methyl-N'-(2,3,4-trifluorophenyl)urea. The formula of the structure is C13H12F3N5O2. The formula, an intramolecular N-H…F, N-…, C-H…O and hydrogen bonds C-H…N and staking interactions π-π along the a axis produce a columnar structure. Bioactivities like herbicidal, plant-growth regulatory, antitubercular and antibacterial activity can be seen in triazine group against Staphylococcus aureus and Escherichia coli.

Two chiral d10metallosupramolecular systems based on an achiral fluorinated Schiff-base ligand have been prepared and characterized. The ZnIIcomplex 1reveals 21helical coordination chains with the inclusion of rare water chains of opposite helix in the perpendicular channels, whereas the CdIIcomplex 2displays the homochiral 1D coordination motifs with 31symmetry and a 3D supramolecular architecture built by C–H···F interactions. [ABSTRACT FROM AUTHOR]

A series of new alkali-metal-based coordination polymers, [Li(H2IMDC)(H2O)]n (1), [Na2(H2IMDC)2(H3IMDC)2(H2O)4]n (2), and [K(H2IMDC)(H2O)]n (3), have been constructed under solvothermal conditions by using imidazole-4,5-dicarboxylic acid (H3IMDC) as ligand. The structure of the complexes has been determined by single-crystal X-ray diffraction and further characterized by elemental analyses, IR spectra, powder X-ray diffraction and thermogravimetric analyses. The single crystal Xray structural studies showed that their structural dimensionalities varying from 1-D zigzag chain, 2-D 44-sql network to 3-D 4,6-connected coordination framework are strongly governed by the ionic radii and coordination geometries of the metal cations. For the first time, the alkali-metal-based coordination polymers were demonstrated to be effective catalysts for the solvent-free ring-opening polymerization (ROP) of ɛ-caprolactone. The catalytic activity of complexes 1–3 depends on the metal cations, increasing in the order Li+ < Na+ < K+. [ABSTRACT FROM AUTHOR]

A new zinc(II)-based coordination polymer {[Zn(5-fip)(tdbpy)] · (DMF)}n (1) {5-H2fip = 5-fluoroisophthalic acid, tdbpy = 4,4'-(2,4,8,10-tetraoxaspiro[5.5]undecane- 3,9-diyl)bispyridine, DMF = dimethylformamide} has been solvothermally synthesized and structurally characterized. Single-crystal X-ray diffraction revealed that complex 1 shows a unique two-dimensional network architecture containing single-stranded [Zn(5-fip)]n and double-stranded helical [Zn(tdbpy)]n chains. The thermal and luminescence properties of complex 1 have also been studied. [ABSTRACT FROM AUTHOR]

Two new Cu(ii) coordination polymers [Cu(Fbtx)(H2btec)(H2O)2]n and {[Cu(Fbtx)(btec)0.5(H2O)2]·H2O}n have been synthesised by hydrothermal reactions of Cu(ii) nitrate with 1,4-bis(1,2,4-triazole-1-ylmethyl)-2,3,5,6-tetrafluorobenzene (Fbtx) and 1,2,4,5-benzenetetracarboxylic acid (H4btec) under different pH conditions. The first complex has a two-dimensional four-connected layer structure with a 44-sql topology, whereas the second has a two-dimensional three-connected brick-wall network. The luminescence properties of the complexes in the solid state and their thermal stabilities have also been studied. [ABSTRACT FROM AUTHOR]

A facile synthesis procedure was built to synthesize zeolitic imidazolate frameworks (ZIFs) ZIF-8 and ZIF-69 under ambient conditions with the prevention of organic solvents. ZIF-69 adsorbent was first introduced in the liquid-phase separation of hexane isomers. A sieving test was carried out using samples of n-hexane (nHEX) or 2-methylpentane (2MP) over two ZIFs and commercial 5A zeolite materials. According to batch adsorption performances and modeling, ZIF-8 exhibits the highest adsorption selectivity and capacity for nHEX, followed by ZIF-69 and 5A zeolite. The equilibrium data at 25 °C show that a significant amount (0.51 g/g) of nHEX and only 0.09 g/g 2MP can be adsorbed in ZIF-8. And the maximum adsorption capacity of nHEX and 2MP on ZIF-69 are 0.34 g/g and 0.10 g/g, respectively. Breakthrough experiments performed at 150 °C with a binary mixture of nHEX/2MP confirm the shape selectivity and adsorption capacities of ZIF-8 toward nHEX at various total pressures from 0.5 to 1.3 MPa and with different feed concentrations, which is attributed to the flexible architecture of ZIF-8 and its excellent shape match with nHEX. [ABSTRACT FROM AUTHOR]

The spontaneous self-assembly reactions of 2,3,5,6-tetrafluorobenzenedicarboxylic acid (H2BDC-F4) with Ca(NO3)2·4H2O in different solvents resulted in the generation of hydrophilic 3D chiral and achiral Ca(II)-organic frameworks {[Ca4(BDC-F4)4(H2O)4]·4H2O}n (1) and [Ca(BDC-F4)(MeOH)2]n (2), respectively. Complex 1 exhibits higher water solubility compared to 2, and further dissolution of 1 in water results in a new achiral crystal, [Ca(BDC-F4)(H2O)4]n (3). All complexes have been characterized by elemental analysis, IR spectroscopy, and single-crystal and powder X-ray diffraction techniques. Complex 1 crystallizes in the tetragonal P41212 chiral space group and features a rare binodal 5-connected network, directed by a unique 3D chiral (10,3)-a water aggregation consisting of two distinct helical arrays. Complex 2 crystallizes in the space group C2/c and has a binodal 4-connected pts net. Complex 3 crystallizes in the space group P21/m and presents a 2D layer framework containing the unprecedented polymeric [CaII-H2O]n chain based on triple μ2-O aqua bridges. The structural discrepancies illustrate the solvent-induced effect on the construction and structural transformation of chiral and achiral coordination frameworks. Moreover, gas (N2 and CO2) adsorption studies show that the dehydrated framework 1a exhibits excellent selective CO2 gas uptake at 195 K. [ABSTRACT FROM AUTHOR]

A fluorinated bis(triazole) ligand, 1,4-bis(1,2,4-triazol-1-ylmethyl)-2,3,5,6-tetrafluorobenzene (Fbtz), was applied to coordinate with a series of MnII, CoII, FeII, and CuII ions, respectively. In comparison with its nonfluorinated analogue 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene (btx), Fbtz is able to build six novel metal-organic frameworks by acting as a versatile bridge combining with the terminal chlorides (1-5) or acetates (6) ligands. The solid-state crystal structures of 1-6 are studied by single-crystal X-ray crystallography to form the following structures: 3D polymers [M(Fbtz)2Cl2]n (1: M = Mn, 2: M = Co), 1D double chain polymers {[M(Fbtz)2Cl2]∙CH2Cl2∙xH2O}n (3: M = Co, x = 1; 4: M = Fe, x = 2), {[Cu(Fbtz)2Cl2]∙4H2O}n (5), and a 1D double-stranded helical polymer {[Cu2(Fbtz)(OAc)2]∙2H2O}n (6). Conformations of Fbtz in 1-6 can be tuned as a result of varying the anions or solvent system, which ultimately form a series of novel coordination frameworks with different supramolecular architectures. The antibacterial activities of all complexes are investigated. Complexes 4 and 5 show a wide range of bactericidal activities to Gram positive (B. subtilis and S. aureus) and negative (E. coli and P. fluorescence) bacterial strains. The synergistic interactions of ligand isomerism and counteranions have profound effects on the supramolecular networks and properties. [ABSTRACT FROM AUTHOR]

A simple and environmentally benign one-pot synthesis of diaryl thioethers by coupling of arylboronic acids with potassium ethyl xanthogenate through a double arylation process has been developed. The aryl thiols were generated in situ, and the reactions proceeded smoothly to give the corresponding products in good to excellent yields under very mild conditions. [ABSTRACT FROM AUTHOR]

With solvent molecules participating in coordination systems, four new Mn IIcoordination polymers of the rigid ligand 2,3,5,6-tetrachloro-1,4-benzenedicarboxylic acid (H 2BDC-Cl 4) have been obtained from different solvent media. Single-crystal X-ray analysis indicates that the coordination arrays of 1− 4vary from 1D fishbone or zigzag chain for 1or 2, 2D (4,4) layer for 3, to 3D SrAl 2coordination network for 4, respectively. In {[Mn(BDC-Cl 4)(py) 2(H 2O) 2](py) 2} n( 1) and {[Mn(BDC-Cl 4)(MeOH) 3](MeOH)} n( 2), pyridine/water (in 1) and MeOH (in 2) molecules act as the monodentate terminal ligands to fulfill the metal coordination spheres. In the case of {[Mn(BDC-Cl 4)(dioxane)(H 2O) 2](dioxane)} n( 3), the aqua ligand is monodentate and the dioxane moiety displays unusual bridging bidentate mode, whereas for [Mn 5(BDC-Cl 4) 5(DMF) 5] n( 4), three Mn IIcenters are connected by four BDC-Cl 4ligands and two DMF molecules to constitute a trimeric unit. These secondary units are extended to the final 3D network with SrAl 2( sra) topology. Significantly, the solvents play an essential role in the crystallization and construction of these coordination frameworks with distinct dimensionality and connectivity. The thermal and photoluminescence properties of complexes 1− 4in the solid state have also been discussed. [ABSTRACT FROM AUTHOR]

The title compound, C20H14F4N4O2, is centrosymmetric. The dihedral angle between the pyridine and benzene ring is 64.8 (4)°. The crystal structure is stabilized by intermolecular N—H...O hydrogen bonding. [ABSTRACT FROM AUTHOR]

Two new Cu(ii) coorclination polymers [Cu(Fbtx)(H2btec)(H2O2)n and {[Cu(Fbtx)(btec)0.5(H2O2)]·H2O·}nhave been synthesised by hydrothermal reactions of Cu(ii) nitrate with 1,4-bis(1,2,4-triazole-1-ylmethyl)-2,3,5,6-tetrafluorobenzene (Fbtx) and 1,2,4,5-benzenetetracarboxylic acid (H4btec) under different pH conditions. The first complex has a two-dimensional four-connected layer structure with a 44-sql topology, whereas the second has a two-dimensional three-connected brick-wall network. The luminescence properties of the complexes in the solid state and their thermal stabilities have also been studied. [ABSTRACT FROM AUTHOR]