Solvent or Temperature Induced Diverse Coordination Polymers of Silver(I) Sulfate and Bipyrazole Systems: Syntheses, Crystal Structures, Luminescence, and Sorption Properties

Three new coordination polymers, [Ag₄(H₂bpz)₄(SO₄)₂]·H₂O (<b>1</b>), [Ag₂(H₂bpz)₂(SO₄)]·3H₂O (<b>2</b>), and [Ag₃(H₂bpz)₄]­(SO₄)_2/3(OH)_5/3·4H₂O (<b>3</b>) have been solvothermally synthesized with Ag₂SO₄ and flexible ligand 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (H₂bpz) in different solvents and temperatures. Complex <b>1</b> is a 2-fold interpenetrated three-dimensional (3D) framework with an uncommon (3,5)-connected hms topology. Complex <b>2</b> is a structural isomer of <b>1</b> and shows a three-connected 2D ths net consisting of interesting 3-fold and 2-fold heterochiral helical chains. Complex <b>3</b> discloses a grid layer structure, containing heterochiral helical chains and an unusual <i>meso-</i>helix. More interestingly, three sets of layers in <b>3</b> stack in different directions, affording an unprecedented 2D + 2D + 2D → 3D polycatenating cationic framework with 1D + 3D porous systems. In <b>1</b>–<b>3</b>, H₂bpz exhibit exobidentate bridging fashions with wide-ranged interpyrazole tilting angles and changeable coordination configurations, such as <i>cis</i> and <i>trans</i> fashions in <b>1</b> and <b>3</b> and uniform <i>trans</i> fashion in <b>2</b>. These lead to the isomeric [Ag­(H₂bpz)]_<i>n</i> arrays of wavelike and helical chains in <b>1</b> and <b>2</b>, respectively. Complexes <b>1</b>–<b>3</b> display solid-state photoluminescence stemming from the ligand-centered fluorescent emissions of H₂bpz. Because of the highly polar framework, <b>3</b> shows excellent adsorption selectivity for CO₂ over N₂

An Unusual Independent 1D Metal−Organic Nanotube with Mesohelical Structure and 1D → 2D Interdigitation

A novel one-dimensional (1D) metal−organic nanotube {[Cd2(ADC)2(bpp)3(H2O)]2·8H2O}n (MONT-1), based on mixed organic ligands, has been synthesized and characterized. MONT-1 presents the first independent 1D metal−organic nanotube with mesohelical structure and a fascinating topology of 1D → 2D interdigital architecture with side arms. This compound also exhibits high thermal stability and blue-shift emission with large intensity enhancement compared with that of the free ligand and can be explored for potential blue luminescent materials

Synthesis and Structures of Two Novel Three-Dimensional Metal−Organic Frameworks: Comprising an Unprecedented Tetraflexure Helix

Two isomorphous three-dimensional metal−organic frameworks, [M(dtb)(4,4′-bipyridine)1.5(H2O)]n (1, M = Ni; 2, M = Co) [dtb = 5,5′-dithiobis(2-nitrobenzoic acid), 4,4′-bipy = 4,4′-bipyridine], have been synthesized by ligating metal ions with V-shaped H2dtb and linear 4,4′-bipy ligands, and they have been characterized structurally by single crystal X-ray diffraction studies and FT-IR and TGA analysis. Complexes 1 and 2 exhibit fascinating interweaved meso-helices and represent the first examples of metal−organic frameworks with four spiral shafts in one helical chain, named a tetraflexural helix. The pitch of the single helical chain is up to 27.741 Å, which is out of the normal scope of helical pitch

Syntheses and Crystal Structures of a Series of Zn(II)/Cd(II) Coordination Polymers Constructed from a Flexible 6,6′-Dithiodinicotinic Acid

Five novel Zn(II)/Cd(II)-based coordination polymers 1–5 with a flexible disulfide derivative of the nicotinate 6,6′-dithiodinicotinic acid (H2cpds) and two rodlike N,N′-donor ligands (bpa =1,2-bi(4-pyridyl)ethane; bpp = 1,3-bis(4-pyridyl)propane) have been successfully synthesized under the liquid diffusion condition and characterized by elemental analysis, IR spectra, and X-ray diffraction, namely {[Zn(cpds)]·H2O}n (1), {[Zn(cpds)(bpa)0.5]}n (2), {[Zn(cpds)(bpp)]}n (3), {[Cd(cpds)(bpa)1.5]·H2O}n (4), and {[Cd2(cpds)2(bpp)·(H2O)3]·4H2O}n (5). Complexes 1–5 display various coordination motifs due to different conformations, and coordination modes of the H2cpds ligand, at the same time the effect of the auxiliary ligands plays important roles in the construction of extended supramolecular networks. Complexes 2–4 all exhibit 2D layer structures, in which 2 displays a 2-fold 2D → 2D parallel interpenetration framework containing a rotaxane-like motif and 3 is a 2D 44 gridlike layer. Compound 4 contains two kinds of 2D chiral layers composed of three types of single-helical chains and two types of double-stranded helices. Two high-dimensional complexes (3D) with a microporous network containing a 1D metal–organic nanotube filled with plenty of free water molecules for 1, and a 3-fold interpenetrating network with (46·64) topology by considering the cadmium dimer unit as a five-connected node for 5, are observed. Solid-state properties of thermal stability, X-ray powder diffractions, and the photoluminescence properties at room temperature for these crystalline materials have been investigated

Solvent or Temperature Induced Diverse Coordination Polymers of Silver(I) Sulfate and Bipyrazole Systems: Syntheses, Crystal Structures, Luminescence, and Sorption Properties

Three new coordination polymers, [Ag₄(H₂bpz)₄(SO₄)₂]·H₂O (<b>1</b>), [Ag₂(H₂bpz)₂(SO₄)]·3H₂O (<b>2</b>), and [Ag₃(H₂bpz)₄]­(SO₄)_2/3(OH)_5/3·4H₂O (<b>3</b>) have been solvothermally synthesized with Ag₂SO₄ and flexible ligand 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (H₂bpz) in different solvents and temperatures. Complex <b>1</b> is a 2-fold interpenetrated three-dimensional (3D) framework with an uncommon (3,5)-connected hms topology. Complex <b>2</b> is a structural isomer of <b>1</b> and shows a three-connected 2D ths net consisting of interesting 3-fold and 2-fold heterochiral helical chains. Complex <b>3</b> discloses a grid layer structure, containing heterochiral helical chains and an unusual <i>meso-</i>helix. More interestingly, three sets of layers in <b>3</b> stack in different directions, affording an unprecedented 2D + 2D + 2D → 3D polycatenating cationic framework with 1D + 3D porous systems. In <b>1</b>–<b>3</b>, H₂bpz exhibit exobidentate bridging fashions with wide-ranged interpyrazole tilting angles and changeable coordination configurations, such as <i>cis</i> and <i>trans</i> fashions in <b>1</b> and <b>3</b> and uniform <i>trans</i> fashion in <b>2</b>. These lead to the isomeric [Ag­(H₂bpz)]_<i>n</i> arrays of wavelike and helical chains in <b>1</b> and <b>2</b>, respectively. Complexes <b>1</b>–<b>3</b> display solid-state photoluminescence stemming from the ligand-centered fluorescent emissions of H₂bpz. Because of the highly polar framework, <b>3</b> shows excellent adsorption selectivity for CO₂ over N₂

Synthesis, Crystal Structure, and Properties of a New Zinc(II) Coordination Polymer With Mixed 4,4′-biphenyldisulfonic Acid and N-Donor Ligands

<p>A new zinc(II) coordination polymer, namely [Zn(bipy)₂(H₂O)₄]<i>_n</i>·<i>n</i>(dsba) (1), has been synthesized by the mixed 4,4′-biphenyldisulfonic acid (H₂dsba) and 4,4′-bipyridine (bipy) ligands with Zinc(II) salt under the common solution evaporation method. The results of the X-ray crystal diffraction analysis show that complex 1 belongs to the monoclinic system with <i>P2₁/c</i> space group. The unit cell constants of complex 1 are <i>a</i> = 9.2579 Å, <i>b</i> = 12.2016 Å, <i>c</i> = 14.447 Å, α = γ = 90˚, β = 93.476˚. Complex 1 exhibits a three-dimensional supramolecular network based on the discrete structure by utilizing various H-bonded interactions. In addition, the properties of complex 1, such as the elemental analysis, FT-IR spectroscopy, X-ray powder diffraction, and fluorescence spectroscopy were also characterized and are discussed in detailed.</p

Syntheses and Crystal Structures of a Series of Zn(II)/Cd(II) Coordination Polymers Constructed from a Flexible 6,6′-Dithiodinicotinic Acid

Five novel Zn(II)/Cd(II)-based coordination polymers 1–5 with a flexible disulfide derivative of the nicotinate 6,6′-dithiodinicotinic acid (H2cpds) and two rodlike N,N′-donor ligands (bpa =1,2-bi(4-pyridyl)ethane; bpp = 1,3-bis(4-pyridyl)propane) have been successfully synthesized under the liquid diffusion condition and characterized by elemental analysis, IR spectra, and X-ray diffraction, namely {[Zn(cpds)]·H2O}n (1), {[Zn(cpds)(bpa)0.5]}n (2), {[Zn(cpds)(bpp)]}n (3), {[Cd(cpds)(bpa)1.5]·H2O}n (4), and {[Cd2(cpds)2(bpp)·(H2O)3]·4H2O}n (5). Complexes 1–5 display various coordination motifs due to different conformations, and coordination modes of the H2cpds ligand, at the same time the effect of the auxiliary ligands plays important roles in the construction of extended supramolecular networks. Complexes 2–4 all exhibit 2D layer structures, in which 2 displays a 2-fold 2D → 2D parallel interpenetration framework containing a rotaxane-like motif and 3 is a 2D 44 gridlike layer. Compound 4 contains two kinds of 2D chiral layers composed of three types of single-helical chains and two types of double-stranded helices. Two high-dimensional complexes (3D) with a microporous network containing a 1D metal–organic nanotube filled with plenty of free water molecules for 1, and a 3-fold interpenetrating network with (46·64) topology by considering the cadmium dimer unit as a five-connected node for 5, are observed. Solid-state properties of thermal stability, X-ray powder diffractions, and the photoluminescence properties at room temperature for these crystalline materials have been investigated

An Unusual Independent 1D Metal−Organic Nanotube with Mesohelical Structure and 1D → 2D Interdigitation

A novel one-dimensional (1D) metal−organic nanotube {[Cd2(ADC)2(bpp)3(H2O)]2·8H2O}n (MONT-1), based on mixed organic ligands, has been synthesized and characterized. MONT-1 presents the first independent 1D metal−organic nanotube with mesohelical structure and a fascinating topology of 1D → 2D interdigital architecture with side arms. This compound also exhibits high thermal stability and blue-shift emission with large intensity enhancement compared with that of the free ligand and can be explored for potential blue luminescent materials

Trinuclear-based Copper(I) Pyrazolate Polymers: Effect of Trimer π-Acid···Halide/Pseudohalide Interactions on the Supramolecular Structure and Phosphorescence

Under different situations, solvothermal reactions of 3,5-diethyl-4-(4-pyridyl)-pyrazole (HL) with CuX or CuX2 (X = Cl, Br, I, and SCN) afforded five copper(I) coordination polymers, {CuX[CuL]3·solvent}n (X = Cl, 1; Br, 2; I, 3; X = SCN and solvent = MeCN, 4) and {Cu2I2[CuL]3}n (5). X-ray diffraction analyses show that all the complexes have trinuclear [CuL]3 (referred as Cu3) secondary building units featuring planar nine-membered Cu3N6 metallocycles with three peripheral pyridyl groups as connectors, which are further linked by CuX or Cu2X2 motifs to generate single- or double-strand chains. Interestingly, the Cu(I) atoms within the Cu3 units in 1−5 behave as coordinatively unsaturated π-acid centers to contact soft halide/pseudohalide X atoms of CuX and Cu2X2 motifs, which lead to novel sandwich substructures of [(Cu3)(Cu2X2)(Cu3)] (X = Br, I, and SCN) in 2−4. In addition, both the π-acid [Cu3]···X contacts and intertrimer Cu···Cu interactions contribute to the one-dimensional (1D) double-strand and 2D/3D supramolecular structures of 1−5. All of these complexes exhibit high thermostability and bright solid-state phosphorescence upon exposure to UV radiation at room temperature. The emissions arise from the mixtures of metal-centered charge transfer, metal to ligand charge transfer, and halide-to-ligand charge transfer excited states, and can be tuned by intermolecular π-acid [Cu3]···halide/pseudohalide contacts

Trinuclear-based Copper(I) Pyrazolate Polymers: Effect of Trimer π-Acid···Halide/Pseudohalide Interactions on the Supramolecular Structure and Phosphorescence

Under different situations, solvothermal reactions of 3,5-diethyl-4-(4-pyridyl)-pyrazole (HL) with CuX or CuX2 (X = Cl, Br, I, and SCN) afforded five copper(I) coordination polymers, {CuX[CuL]3·solvent}n (X = Cl, 1; Br, 2; I, 3; X = SCN and solvent = MeCN, 4) and {Cu2I2[CuL]3}n (5). X-ray diffraction analyses show that all the complexes have trinuclear [CuL]3 (referred as Cu3) secondary building units featuring planar nine-membered Cu3N6 metallocycles with three peripheral pyridyl groups as connectors, which are further linked by CuX or Cu2X2 motifs to generate single- or double-strand chains. Interestingly, the Cu(I) atoms within the Cu3 units in 1−5 behave as coordinatively unsaturated π-acid centers to contact soft halide/pseudohalide X atoms of CuX and Cu2X2 motifs, which lead to novel sandwich substructures of [(Cu3)(Cu2X2)(Cu3)] (X = Br, I, and SCN) in 2−4. In addition, both the π-acid [Cu3]···X contacts and intertrimer Cu···Cu interactions contribute to the one-dimensional (1D) double-strand and 2D/3D supramolecular structures of 1−5. All of these complexes exhibit high thermostability and bright solid-state phosphorescence upon exposure to UV radiation at room temperature. The emissions arise from the mixtures of metal-centered charge transfer, metal to ligand charge transfer, and halide-to-ligand charge transfer excited states, and can be tuned by intermolecular π-acid [Cu3]···halide/pseudohalide contacts