Syntheses and crystal structures of novel silver(I) coordination polymers based on linear or tetrahedral coordination environments

Two coordination polymers containing Ag(I) atoms, {[Ag(3-pia)](PF₆)}_n (1) and {[Ag(3-pia)₂](PF₆)}_n (2) (3-pia = N-pyridin-3-yl-isonicotinamide), have been synthesized using different solvents, and characterized by single X-ray analyses. In compound 1, Ag(I) atoms are linearly coordinated by two 3-pia ligands, resulting in one-dimensional chains. On the other hand, in compound 2, Ag(I) atoms are tetrahedrally coordinated by four 3-pia ligands, resulting in two-dimensional sheets.     

Microporous rare-earth coordination polymers constructed by 1,4-cyclohexanedicarboxylate

In this paper, three novel microporous materials of 1, 4-cyclohexanedicarboxylate Ln[(C₈H₁₀O₄)_1.5(H₂O)] · 0.5(H₂O) (Ln = Eu for 1, Nd for 2, Sm for 3) are synthesized by the hydrothermal method. The powder X-ray diffraction patterns demonstrate three complexes are isomorphism. The crystal structure of the coordination polymer 1 reveals that the Eu³⁺ ion center is located in the nine-coordinated environment and the carboxyl groups chelate Eu³⁺ ions to form 1-D channels through c-axis in μ_1, μ₂ and μ₃ fashion. The properties of the microporous materials are all characterized by the adsorption and desorption of the nitrogen gas and show tremendous difference. TGA illustrate the open frameworks are stable to about 450 °C and they are retained upon removal of water molecules in channels.     

A self-assembled supramolecular solid for catalytic application

A 1,8-naphthalenecarboxylic anhydride-4,5-dicarboxylate (L) bridged copper(II) dimeric molecular module [Cu₂L₂(DMF)₂(H₂O)₂] (1) can self-organize into a solid-state supramolecular architecture. The combination of the multitopic contact sites of hydrogen bonds coupled with two bulky aromatic cores promoted the molecule to self-link into a solid-state supramolecular architecture, which was almost insoluble in water and common organic solvents. Solid 1 can heterogeneously catalyze the cross-coupling of arylboronic acids with imidazole in the absence of a base or additive to generate the corresponding coupling products in excellent yields in methanol at 50 °C, which can be recovered and recycled by a simple filtration and was used for six consecutive cycles with consistent activity.     

Solvent-induced supramolecular isomers: Two dimensional coordination polymers constructed by Cu(II) and fluconazole

Two Cu(II)–fluconazole supramolecular isomers 1 and 2 formulated as (flu)₂Cu(SCN)₂ (flu = fluconazole) have been synthesized and structurally characterized by single crystal X-ray diffraction. Different solvent media lead to the different binding modes of anion SCN⁻ and the flexible C–C chain of fluconazole has been rotated in the two isomers. Complex 1 exhibits a two dimensional square grid-like layer and complex 2 exhibits a two dimensional framework with a parquet motif. Different H-bonds and stacking modes are observed in the two isomers. Complex 1 is nonemissive, whereas complex 2 exhibits photoluminescence property.     

New highly ordered hydrophobic siloxane-based coordination polymers

Two H-bond polymers from carboxypropyl disubstituted disiloxane and bipyridyl compounds, as well as the starting components in different ratios were reacted with zinc acetate. Two new siloxane-containing coordination polymers were thus obtained and characterized. They exhibited highly ordered structures, which were investigated by single crystal XRD. One of the H-bond polymers, as well as a third coordination polymer, without the siloxane component (obtained as secondary product) were also structurally characterized. The siloxane coordination polymer obtained with 4,4′-bipyridyl has a 2D MOF structure. The homologous polymer derived from 1,2-(4-bipyridyl)ethylene forms undulated 2D-layers which are packed in the crystal leading to partial interpenetration with formation of two types of channels along crystallographic axis c. The new siloxane-containing coordination polymers were investigated by FT-IR, DSC–TG–TGA, DVS and static contact angle measurements. They are hydrophobic (by contact angle) and even superhydrophobic effect was observed on bulk powder for one of them. The solvent sorption capacity was measured by tensiometry. They were tested for catalytic activity in H₂O₂ decomposition and preliminary experiments for oxidation of glucose and viscose were done.     

Role of main chain rigidity and side-chain substitution on the supramolecular organization of rigid-flexible polymers

The synthesis, characterization and supramolecular organization of rigid-flexible aromatic-aliphatic polyethers are reported. The polymers contain substituted quinquephenyl moieties along their main chains separated by flexible aliphatic units of various lengths. The oligophenylene segments bear different types of dodecyloxy tailed side groups, either attached on the periphery of side dendritic wedges (G₁) or as direct side-chains (G₀). Their structural characterization was performed by means of differential scanning calorimetry, polarizing optical microscopy and X-ray scattering from oriented fibers. These techniques revealed the presence of supramolecular organization in different levels and in the absence of solvent, reflecting a delicate balance of interactions produced by the rigid-flexible backbone segments and the size of dendritic side-chains. It was concluded that the polymers with only two dodecyloxy side-chains (zeroth generation, G₀) possess smectic order. On the other hand, substitution of the quinquephenyl backbone with the dodecyloxy decorated dendrons (first generation, G₁) disrupts the lateral order giving rise to a nematic state. These results are compared with the corresponding rigid-flexible polyethers having terphenyl rigid segments.     

Two-dimensional coordination polymer with tellurium nodes

Bis(diphenylphosphino)hexane disulfide and TeCl₄ afforded layered network coordination polymer with Te(II) nodes. The two-dimensional nets are positively charged, the anions and form layers alternating the polymeric networks.     

Physicochemical properties of some new coordination polymers

Coordination polymers of Cu(II), Ni(II), CO(II), Mn(II), Zn(II), oxovanadium (IV), and dioxouranium(VI) with 2-hydroxy-4-methoxyacetophenone thiourea trioxane polymer were synthesized. Elemental analyses of the coordination polymers indicate a metal-to-ligand ratio of 1:2. The diffuse reflectance spectra and magnetic moments of coordination polymers show a distorted octahedral structure. Infrared spectral studies show that the metals are coordinated through the oxygens of carbonyl and phenolic groups and the nitrogen of thioamide group. Thermal stabilities of coordination polymers were determined by thermogravimetric analysis. Semiconducting behavior of the polymer and its coordination polymers was also studied by electrical conductivity measurements at different temperatures.     

Two 1D [CuxIx]-based coordination polymers of tetraphosphine ligands

Diffusion reactions of CuI with N,N,N′,N′-tetra(diphenylphosphanylmethyl)ethylene diamine) (dppeda) and 1,4-N,N,N′,N′-tetra(diphenylphosphanylmethyl)benzene diamine (dpppda) in MeCN/toluene in a zigzag glass tube or solvothermal reactions of CuI and dppeda or dpppda in MeCN produced two [Cu_xI_x]-based coordination polymers, [Cu₂I₂(dppeda)]·2MeCN (1·2MeCN) and [Cu₄I₄(dpppda)]·MeCN (2·MeCN), respectively. Both compounds were characterized by elemental analysis, IR spectroscopy, ¹H and ³¹P{¹H} NMR, ESI-MS and thermogravimetric analysis, and their structures were determined by single crystal X-ray diffraction. In 1, [Cu₂I₂] cores are interconnected by dppeda ligands in a μ-η²:η² end-to-end mode to form a 1D chain, while in 2 stair-like [Cu₄I₄] cores are linked by dpppda ligands in a unique Z-shaped μ-η²:η² side-by-side mode to produce the other kind of 1D chain.     

纳米多孔配位聚合物的研究进展

纳米多孔材料可用作催化剂、气体储存材料和光电子器件,是目前新型多孔材料的研究热点之一.借助自组装技术,选择羧酸类、联吡啶类和吡啶羧酸类化合物作为桥联配体,可获得一维、二维和三维的多孔配位聚合物.简要综述了该类纳米多孔配位聚合物的设计原理、合成路线和应用前景,评价了其合成方法的优缺点.由于其特殊的结构和性质,纳米多孔配位聚合物将发展成为具有光、电、磁等性质的多功能材料.     

1-D and 2-D lanthanide coordination polymers constructed from 4-sulfobenzoate and 1,10-phenanthroline

Two complexes {[Dy₂(4-SBA)₃(phen)₂(H₂O)₄] · 2H₂O}_n (1) and {[Eu₂(4-SBA)₃(phen)₂(H₂O)₂]}_n (2) (4-SBA = 4-sulfobenzoate, phen = 1,10-phenanthroline) were synthesized and their structures were determined by X-ray crystallography. The 1 has a 1-D chain structure by bidentate and tridentate 4-SBA ligands as linkages and 3-D network was formed by strong hydrogen bonds. The 2 has a 2-D network structure by tridentate and tetradentate 4-SBA ligands as linkages. The luminescence properties and thermal stability of the two complexes were investigated.     

3D supramolecular network constructed by intermolecular interactions in mixed ligand complex of zinc

New complex [Zn(quin-2-c)₂(Him)₂] (quin-2-c = quinoline-2-carboxylate ion, Him = imidazole) was synthesized by self assembly and its structure was determined by X-ray analysis. The compound crystallizes in P21/c space group. Four independent molecules of complex are present in the structure. Strong hydrogen bonds create three different 1D chains which are collected in two different layers. The alternately packed layers form the 3D supramolecular structure. The interchain and interlayer contacts are of the C–HO, ππ and C–Hπ type. The influence of strong hydrogen bond on the vibrational characteristics of the monodentately coordinated carboxylate group in zinc complexes with quin-2-c ion is discussed.     

Experimental and theoretical study on a novel supramolecular complex constructed from benzenetetracarboxylatic acid and 1,2,3,4-tetra(4-pyridlyl)thiophene

Hydrothermal reaction of benzenetetracarboxylatic acid (H₄BTC) with 1,2,3,4-tetra(4-pyridlyl)thiophene (TPT) afforded a novel supramolecular complex [(H₄BTC))(TPT)]_n (1), which was characterized by FT-IR spectroscopy, elemental analysis, luminescence and thermogravimetric analysis. X-ray single-crystal diffraction reveals that 1 exhibits a one-dimensional (1-D) wave-shape chain assembled through strong hydrogen bonds. Density functional theory (DFT) calculations show that the optimized structures closely resemble the experimental structures. The electronic absorption spectrum of the model dimer in its singlet state has been studied by a time-dependent DFT (TD-DFT) calculation and the nature of the molecular orbitals involved in the fluorescent property was verified.     

Effect of self-complementary motifs on phase compatibility and material properties in blends of supramolecular polymers

Applicability of supramolecular polymers blending in preparation of materials with tunable properties is reported. The effect of strongly dimerising 2-ureido-4[1H]-pyrimidinone (UPy) end groups on phase compatibility in binary polymer blends was studied. A low molecular weight poly(tetrahydrofuran) diol was functionalized with UPy moieties (PTHF(UPy)₂, a soft material) and mixed with varying amounts of low molecular weight UPy functionalized polycaprolactone di- and triol (PCL(UPy)₂ and PCL(UPy)₃, both relatively strong and stiff materials). Thermal studies showed that T_g of the homopolymers shifted to intermediate temperatures. AFM observation suggested that the phase domain decreased significantly after UPy functionalization of diols. Also the mechanical properties improved at a higher rate than those predicted by the rule of mixtures. These findings indicate that blend components are placed in intimate contact as a result of the UPy-UPy interactions. The reversible crosslinking by PCL(UPy)₃ gave better control still over the mechanical properties of the supramolecular polymer blends.     

Study on the thermal-induced shape memory effect of pyridine containing supramolecular polyurethane

In this paper, a series of pyridine containing supramolecular polyurethanes (PUPys) were synthesized from BINA, HDI and BDO. Then the structure, morphology and thermal-induced shape memory effect (SMEs) of PUPys were investigated systematically. Results show that strong hydrogen bonding is formed in the urethane group as well as in the pyridine ring; and phase separation consisting of soft phase and hard phase occurs in the PUPy. In addition, it is found that the lower limit of BINA content for PUPys exhibiting good SMEs is 30 wt%. PUPys with higher BINA content show higher shape fixity, higher shape recovery and better strain stability. Moreover, the shape recovery force increases with the decreasing of BINA content. Finally, the temperature-dependent FT-IR spectra support that the hydrogen bonding in the pyridine ring serves as the molecular switch; while the hydrogen bonding in the urethane groups acts as the physical netpoints for the utilization of PUPys as SMMs.     

An unexpected sulfinate–sulfonate mixed coordination polymer of copper(II)

By reaction of copper nitrate trihydrate and 2,2′-dipyridyldisulfide in both aerobic and anaerobic conditions, the mixed [{Cu(2-pySO₂)₂}_n]–[{Cu(2-pySO₃)₂}_n] coordination polymer of copper(II) (1) has been synthesized. The X-ray diffraction analysis indicates that complex 1 exhibits an infinite one-dimensional polymeric chain consisting of [Cu(C₅H₄N)₂] building units connected by SO₂/SO₃ groups. The atom which has been labelled O3 is only present in 60% of the molecules. Complex 1 exhibits a very weak ferrogmagnetic spin coupling (zJ = +0.40 cm⁻¹).     

Structure and magnetic properties of a copper malonate/dipyridylamine layered coordination polymer with both syn–anti and anti–anti copper carboxylate chains

The novel 2-D copper metal–organic layered coordination polymer {[Cu₂(malonate)₂(dpa)(H₂O)₂] · H₂O} (1, dpa = 4,4′-dipyridylamine) has been prepared and characterized by single-crystal X-ray diffraction, IR and thermogravimetric analysis. The structure of compound 1 consists of alternating syn–anti and anti–anti copper malonate 1-D chains linked into a (6,3) herringbone layer motif through tethering dpa ligands. Variable temperature magnetic studies indicate weak ferromagnetic coupling through the 1-D copper malonate chains with J = 0.64(1) cm⁻¹ and g = 2.033(4).     

[Zn(BDC)(H2O)2]n: a novel blue luminescent coordination polymer constructed from BDC-bridged 1-D chains via interchain hydrogen bonds (BDC = 1,4-benzenedicarboxylate)

A novel coordination polymer [Zn(BDC)(H₂O)₂]_n 1 (where BDC = 1,4-benzenedicarboxylate), has been synthesized and characterized by X-ray diffraction. 1 crystallizes in the monoclinic space group C2/c, a=15.09(2) Å, b=5.058(7) Å, c=12.196(16) Å, β=103.62(2)°, , Z=4. The most striking feature of 1 is that it consists of a high-dimensional network structure constructed from BDC-bridged 1-D chains via interchain hydrogen bonds. The coordination sphere of the zinc(II) ion is a distorted tetrahedron completed by four oxygen atoms from two water molecules and two BDC ligands. BDC adopts the bis-monodentated (syn–anti) coordination mode linking two adjacent zinc(II) ions. 1 shows strong blue photoluminescence as the result of the fluorescence from the intraligand emission excited state.