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The article discusses research on a robust porous three-dimensional cadmium-framework with selective sorption for carbon dioxide and tunable luminescence. It cites the potential applications of porous coordination polymers (PCPs) including gas adsorption, molecular storage and heterogenous catalysis. The processes used and other details of the experiment are presented.

Through a two-step synthetic strategy, four d10Schiff-base complexes CdZn(DMF)(La)(NO3)2(1), Cd[Zn(La)Cl]2·H2O (2) and [Cd(DMF)LbS]2·2H2O (S = NO3, 3; Cl, 4) (H2La= N,N′-bis(3-methoxy-salicylidene)phenylene-1,2-diamine, HLb= 2-(1H-benzoimidazol-2-yl)-6-methoxy-phenol) have been successfully constructed by the solvothermal reaction of Cd(NO3)2/CdCl2with Zn(La)/Zn(Lb)2, and characterized by EA, IR, FAB-MS and TG, in which 1, 2and 4were confirmed by single crystal X-ray diffraction. The results reveal that 1is the first 3d-4d hetero-dinuclear compound based on H2La, however, 2is a CdZn2-type compound reported previously. 3and 4are the first examples of dinuclear compounds containing ligand HLb. Moreover, luminescence and biological activities of the four compounds and two ligands H2La/HLbare investigated. [ABSTRACT FROM AUTHOR]

Under different temperatures, the reaction mixture of the multidentate organic ligand usy-L4and Zn(NO3)2+ NaN3crystallized to give three conformational isomers, namely Zn(usy-L4)(η1-N3)2(α-1, β-2and γ-3) (usy-L4= N,N-dimethyl-2-(pyridin-2-ylmethylimino)ethanamine). Single-crystal X-ray diffraction analyses reveal that the conformational isomerism of three compounds 1–3stems from the different orientations of two azide groups with η1-terminal nitrogen atom coordinating to central zinc ion in reference to the basal chelating plane of ligand usy-L4, and further resulting in different supramolecular networks with two-dimensional 44rhombic-grid for α-1, a three-dimensional 36·418·53·6 compressed-NbO framework for β-2, and a three-dimensional “dense” 424·64topology for γ-3. Meanwhile, three isomers may be also irreversibly converted from 1to 2, to 3through SC-to-SC transformation driven by temperature. [ABSTRACT FROM AUTHOR]

Through different synthetic strategies, four dinuclear cadmium(ii) complexes containing N2O/N2O2donor tridentate/tetradentate asymmetrical Schiff base ligands have been synthesized and characterized. The two complexes [Cd(L1)(μ2-Cl)(CH3OH)]2(1) and [Cd(L2)Cl]2·CH3OH (2) are constructed, respectively, from self-assembly of a Cd2+ion with two asymmetrical Schiff base ligands, namely 2-((2-(dimethylamino)ethylimino)methyl)phenol (HL1) and 2-((2-(dimethylamino)ethylimino)methyl)-6-methoxyphenol (HL2). However, viasingle-crystal to single-crystal structural transformations driven by temperature, the other two corresponding compounds [Cd(L1)Cl]2(1a) (1→ 1a) and [Cd(L2)Cl]2(2a) (2→ 2a), with N2O2Cl and N2O3Cl donors, respectively, can be obtained. Obviously, the synthetic strategies presented in the text provide very effective methods for constructing the dinuclear CdIIcompounds with N2O/N2O2donor tridentate/tetradentate asymmetrical Schiff base ligands. Meanwhile, the strong fluorescence emission of 1and 2makes them potentially useful photoactive materials. [ABSTRACT FROM AUTHOR]

Several 0D, 1D, and 3D metal–organic hybrid frameworks of ZnIIhave been synthesized by using the asymmetric ligand 6-(1H-benzoimidazol-2-yl)pyridinecarboxylic acid (HL) with control of the temperature and solvent in a solvothermal synthesis technique. In DMF, the structure at room temperature confirms that the resulting compound Zn(L)2·2(H2O) (1) is the 0D mononuclear structure, above ∼80 °C, C–N bond cleavage of partial DMF molecules induces the formation of the 1D chain-like compound {[Zn(L)(HCOO)]·2(H2O)}n(2), but on warming up to 120 and 160 °C, due to the decomposition of a large number of DMF molecules, the same reaction, respectively, gives two 3D metal–organic coordination polymers with 3D channels reported previously {[Zn(HCOO)3]−·[H2N(CH3)2]+}n(3) and [Zn(HCOO)2]n(4), in which the 3D channels of 3contain guest [H2N(CH3)2]+motifs, while at high temperature the 3D channels of 4are an open stable system without any guest molecules. Replacing DMF in the above reaction by ethanol or acetonitrile, only 0D compound 1is obtained in the range from room temperature to 160 °C. However, the same reaction in DMSO provides a 1D wave-like compound {[Zn(L)(DMSO)]·(ClO4)·H2O}n(5), in which the solvent DMSO molecule coordinates to the central metal ZnIIion. Furthermore, in three new complexes 1, 2and 5, through ππ stacking and hydrogen bonding interactions, 3D supramolecular networks are assembled. It is worth noting that the existence of the twelve-membered cyclic water–perchlorate dimers [(ClO4)(H2O)]22−with chair-conformation in the solid state of 5not only increases the stability of the supramolecular structure, but also results in a stronger fluorescence signal compared with ligand HL, 1and 2. [ABSTRACT FROM AUTHOR]

Abstract  Two mononuclear complexes with the Schiff base ligand 2-((2-(dimethylamino)ethylimino)methyl)phenol (HL), namely ZnL2 and CoL2(N3), have been synthesized and characterized using single-crystal X-ray diffraction and spectroscopy (IR, 1H NMR, UV–Vis, MS and EA). Both complexes are mononuclear. The coordination geometry in the Zn(II) complex is distorted square-pyramidal with a weak Zn···N interaction. The Co(III) complex is distorted octahedral, and the neutral molecule unit [CoIIIL2(N3)] is connected by C–H···N hydrogen bonds to form a one-dimensional infinite chain. The luminescence of the zinc compound has been investigated. [ABSTRACT FROM AUTHOR]

Two new isomeric 8-hydroxyquinoline derivatives with quinoline groups have been synthesized by Perkin condensation. Their structures were characterized by EI-MS, 1H NMR spectroscopy, elemental analysis and FT–IR spectroscopy; crystal structures were determined by X-ray crystallography. 2-[2-(Quinolin-2-yl)vinyl]-8-hydroxyquinoline crystallizes in the tetragonal space group I41/ a and 2-[2-(quinolin-4-yl)vinyl]-8-hydroxyquinoline crystallizes in the monoclinic space group P21/ n. Hydrogen bonds and intermolecular interactions are observed in the compounds and stabilize their structures. The biological activities were investigated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay and flow cytometry analysis, and the results revealed that the two compounds had effects on the proliferation of rat mesenchymal stem cells. [ABSTRACT FROM AUTHOR]

Two complexes of the achiral tripodal ligand tris(1-benzimidazolylethyl)amine (nteb), viz., [Mn(nteb)[sub 2](H[sub 2]O)[sub 2]](CIO[sub 4])[sub 2].CH[sub 3-] OH, 1, and [Ag[sub 2](nteb)[sub 2]](CF[sub 3]CO[sub 2])[sub 2]·.2H[sub 2]O, 2, have been synthesized and characterized by IR, ¹H NMR, and EPR spectroscopy (1), electrospray mass spectrometry, thermogravimetric analysis, and X-ray crystallography. Compound 1 contains chiral complex cations due to the same handedness of two nteb ligands (δδ or λλ) but crystallizes as a racemate, while 2 contains a dinuclear mesocate because of the opposite handedness (δλ) of two nteb ligands. Crystal data for 1: space group P&1macr; with a = 9.471(4) Å, b = 16.884(7) Å, c = 19.906(8) Å, α = 77,930(7)°, β = 88.063(7)°, γ = 89.706(7)°, V- 3111(2) ų, and Z- 2. Crystal data for 2: space group P&1macr; with a = 9.3390(12) Å, b = 10.2168(13) Å, c = 16.382(2) Å, α = 75,721(3)δ, β = 87.857(3)δ, γ = 71.738(3)δ, V 1437.2(3) ų, and Z = 1. In 1, water serves as an auxiliary ligand, connected to one imidazole N atom of each nteb ligand through a H-bridge; the cationic complexes are associated intermolecularly via π ... π interactions. In contrast to 1, the coordination to the Ag[sup +] ions in 2 occurs in a heterochiral manner and produces a dinuclear mesocate. [ABSTRACT FROM AUTHOR]

A direct and facile synthesis of highly functional 5-aza-spiro[2,4]heptanes, a valuable structural motif for drug discovery, is developed viacatalytic asymmetric 1,3-dipolar cycloaddition of cyclopropylidene acetate and azomethine ylides for the first time. [ABSTRACT FROM AUTHOR]

The title compound, C16H16N5+·Cl− (nbbH+·Cl−), displays N—H⋯N, N—H⋯Cl and π–π inter­actions in the crystal packing. The Cl− anion is chelated by the nbbH+ cation via two N—H⋯Cl hydrogen bonds. Inter-ion N—H⋯N and N—H⋯Cl hydrogen bonds link ions related by 21 screw axes into chains along the c axis. These chains are further linked by glide-plane operations to generate a three-dimensional network, which is additionally stabilized by inter­chain π–π inter­actions. [ABSTRACT FROM AUTHOR]

Molecules of the title compound, C20H16N6.4H2O, lie across crystallographic inversion centres. The dihedral angle between each benzotriazole moiety and the central benzene ring is 74.95 (9)°. In the crystal structure, the molecular organization is stabilized by well defined weak C—H⋯π, π–π, O—H⋯O and O—H⋯N intermolecular interactions, leading to the formation of a two-dimensional network. [ABSTRACT FROM AUTHOR]

In the title compound, [CdCl(C12H8N2)2(H2O)]2(C10H8O6)·1.5H2O, the CdII atom is coordinated by four N atoms from two phenanthroline ligands, one Cl ligand and one water mol­ecule, and displays a distorted octa­hedral geometry. The anion is centrosymmetric. The packing is governed by inter­molecular hydrogen bonds and a π–π stacking inter­action. [ABSTRACT FROM AUTHOR]

In the title compound, C14H10O4S2·2C3H7NO, the dithio­disalicylic acid is hydrogen bonded to dimethyl­formamide solvent mol­ecules. Within the dithio­disalicylic acid, the two benzene rings are nearly perpendicular to each other, with a dihedral angle of 77.77 (10)°. [ABSTRACT FROM AUTHOR]

A series of Mn(II), Cd(II), and Co(II) metal–organic frameworks, namely, {[Mn(L1)(NCS)2(CH3OH)2]·2(CH3OH)}n(1), {[Mn(L2)2(NCS)2(CH3OH)2]}n(2), {[Mn(L3)2(NCS)2]·0.5(CH3OH)·4.5H2O}n(3), {[Cd(L1)(I)2]·3(H2O)}n(4), {[Cd(L2)(I)2]}n(5), {[Cd(L3)(NCS)2]·2.5(H2O)}n(6), {[Co(L1)2(NCS)2]·4(H2O)}n(7), {[Co(L2)2(NCS)2]·(HCCl3) }n(8), and {[Co(L3)2(NCS)2]·3(H2O)}n(9) (where L1= N,N′-bis(4-pyridylmethyl)-pyromellitic diimide, L2= N,N′-bis(3-pyridylmethyl)-pyromellitic diimide, L3= N,N′-bis(4-pyridylmethyl)-naphthalene diimide), were synthesized and structurally characterized by elemental analyses, thermogravimetric (TG) analyses, powder X-ray diffraction, IR spectroscopy, and single-crystal X-ray diffraction. In Mn(II) complexes 1–3, L1connects the adjacent metal centers to form an infinite one-dimensional (1D) zigzag coordination polymeric chain, L2acts as a monodentate ligand to give mononuclear coordination motifs, while L3bridges two metal ions to generate two-dimensional (2D) networks of the (4, 4) net topology containing rhombic grids. In Cd(II) complexes 4–6, L1, L2, and L3act as bidentate ligands and coordinate with two metal ions to form three different coordination polymers that display diversified structures, that is, infinite 1D zigzag chain in 4, single-stranded double helical chain in 5, and 2D networks of the (4, 4) net in 6. For three Co(II) complexes, 7is a three-dimensional (3D) framework with 3-fold interpenetrating diatopology, while 8and 9have similar two-dimensional (2D) networks of the (4, 4) net topology. The results show that the conformation and coordination mode of organic ligands and the coordination geometry of metal centers play important roles in determining the structure and topology of the complexes. Furthermore, the gas sorption properties were measured, and complex 7shows a highly selective sorption behavior toward CO2, which can be a promising candidate as adsorbents for CO2/N2separation. In addition, the luminescence properties of 5–6were studied in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

The two flexible multidentate ligands 1,3-bis(8-thioquinolyl)propane (C3TQ) and 1,4-bis(8-thioquinolyl)butane (C4TQ) were reacted with AgX (X = CF[sub 3]SO[sub 3, sup -] or CIO[sub 4, sup -]) to give four new complexes: {[Ag(C3TQ)](CIO[sub 4])}[sub n] 1, {[Ag(C3TQ)](CF[sub 3]SO[sub 3])}[sub n] 2, {[Ag[sub 2](C4TQ)(CF[sub 3]SO[sub 3])(CH[sub 3]CN)](CF[sub 3]SO[sub 3])}[sub n] 3, and {[Ag(C4TO)](ClO[sub 4])}[sub n] 4. All complexes have been characterized by elemental analysis, IR, and ¹H NMR spectroscopy. Single-crystal X-ray analysis showed that chain structures form for all complexes in which the quinoline rings interact via various intra- (1) or intermolecular (2, 3, and 4) π-π aromatic stacking interactions, which in the latter cases results in multidimensional structures. Additional weak interactions, such as Ag···O and Ag···oS contacts and C-H···O hydrogen bonding, are also present and help form stable, crystalline materials. It was found that the (CH[sub 2])[sub n] spacers (n = 3 or 4) affect the orientation of the two terminal quinolyl rings, thereby significantly influencing the specific framework structure that forms. If the same ligand is used, on the other hand, then the different counteranions have the greatest effect on the final structure. [ABSTRACT FROM AUTHOR]

The title praseodymium coordination polymer, {[Pr2(C10H8O6)3(H2O)2]·2H2O} n, was obtained by the hydrothermal reaction of Pr(NO3)3 with ( p-phenylenedioxy)diacetic acid in alkaline aqueous solution. Each PrIII atom is coordinated by nine O atoms, eight from four ( p-phenylenedioxy)diacetate ligands and one from a water molecule, displaying a tricapped trigonal prismatic geometry. There is a centre of symmetry at the mid-point of the Pr...Pr vector. The bridging ligands crosslink the metal ions to form a three-dimensional network, with channels running along the c axis in which the uncoordinated water molecules are located. The crystal structure is stabilized by intermolecular O—H...O hydrogen-bonding interactions. [ABSTRACT FROM AUTHOR]

In the title compound, [Fe(C3H2N3O3)(H2O)5](C3H2N3O3)·2H2O, the FeII atom exhibits an FeNO5 octahedral coordination geometry arising from one N-bonded 1,3,5-triazinanyl-2,4,6-trione molecule and five O atoms of water molecules. The uncoordinated 1,3,5-triazinanyl-2,4,6-trione anion and uncoordinated water molecules interact with the cation through O—H...O, O—H...N and N—H...O hydrogen bonds, generating a three-dimensional network. [ABSTRACT FROM AUTHOR]

In the title compound, C13H10N2O, the benzimidazole system is nearly coplanar with the phenol ring, with a small dihedral angle of 8.11 (5)°. Intermolecular N—H...O and O—H...N hydrogen bonding helps to stabilize the crystal structure. [ABSTRACT FROM AUTHOR]

In the title compound, [Ag(C3H4N2)2)]NO3, the AgI atom exhibits an approximately linear coordination geometry formed by two N atoms of imidazolium cations. The uncoordinated nitrate anion is linked to the AgI complex via N—H...O hydrogen bonding, generating a one-dimensional supramolecular chain. [ABSTRACT FROM AUTHOR]