Self-penetrating Network Research Articles

Rational design of hydrothermal in situ ligand synthesis to fabricate two new coordination polymer

Two novel compounds, [Cu3I3(TPC)0.5(BPP)2]n (1) and [Cu2Cl2(TPC)0.5]n (2) (TPC=1-hydroxy- 1,2,4,5-tetra(4-pyridyl)cyclohexane ligand, bpp=1,3-dipyridyl-propane ligand)have been hydrothermally synthesized and structurally characterized by elemental analyses, IR and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that 1 and 2 are constructed by the hydrothermal in situ formation of a tetradentate ligand, TPC, through dehydrogenative coupling and hydroxylation of 1,3-bis(4-pyridyl)propane molecules. Compound 1 is three-dimensional self-penetrating network constructed in situ ligands and the original ligand which has rarely been reported in metal–organic frameworks (MOFs). Compound 2 is a chain structure with TPC. The rational design strategy in this article will facilitate the application in the construction of new MOFs or in situ ligand synthesis. Furthermore, the solid-state photoluminescent properties have also been investigated for 1 and 2. (CCDC: 1995908, 1; 2058314, 2).

A zinc(II) sulfate-based porous framework with new topology and its usage as catalyst in Friedel–Crafts alkylation reaction

An unprecedented three-dimensional supramolecular MOF, namely [Zn3(bpy)3 (SO4)4]·(Me2NH2)2·DMF·9H2O (1, where bpy = 4,4′-bipyridine, DMF = N,N′-dimethylformamide), has been efficaciously synthesized under the solvothermal reaction. A single-crystal structure determination showed that the wavelike [Zn3(bpy)(SO4)4] layers are pillared by pairs of bpy ligands to give a new 4,6-connected binodal self-penetrated network with overall (4264)(42687382) topology. 1 also has been fully identified characterized by thermogravimetric analysis, gas adsorption properties and so on. In addition, a new Cu(II)-MOF (cat1) was further prepared by postsynthetic exchange (PSE) synthetic approach based on compound 1, which is proved to be an active catalyst for the Friedel–Crafts reaction of indole with β-nitrostyrenes. The result from this work provides a new attempt to describe the crystallization of inorganic sulfate anion link to the organic functional group, and the functionalization-induced MOF gain insights for designing new functional MOF.

A cobalt coordination polymer with a new 6-connected self-penetrated topology and its high temperature layered polymorph

Crystals of {[Co2(cpp)2(dpa)2]·2.5 H2O}n (1, cpp = 3-(4-carboxyphenyl)propionate, dpa = 4,4′-dipyridylamine) were prepared by hydrothermal methods. A single-crystal structure determination showed the presence of 2-fold interpenetrated lvt topology [Co2(cpp)2]n networks, which feature ferromagnetically coupled {Co2(OCO)2} dimeric units. The interpenetrated [Co2(ccp)2]n networks are pillared by pairs of dpa ligands to give an unprecedented dimer-based 6,6-connected binodal self-penetrated network with overall (32556672)(34425465) topology. A higher temperature synthetic scheme afforded [Co(cpp)(dpa)(H2O)]n (2), which displays a simpler (4,4) grid sawtooth layered topology.

Diverse stacked and entangled topologies in cadmium tricarballylate coordination polymers with nitrobenzene detection capability

Hydrothermal reaction of cadmium salts, tricarballylic acid (H3tca) and dipyridyl ligands resulted in generation of four coordination polymers that were characterized by single-crystal X-ray diffraction. The nature of the ancillary dipyridyl ligand plays a primary role in enforcing differing structural topologies across the series of new phases. [Cd2(tcaH)2(dpe)2]n (1, dpe = 1,2-di(4-pyridyl)ethane) displays a 2-fold interpenetrated 3D 41263pcu net based on 6-connected {Cd2(O)(OCO)} cluster nodes. [Cd(tcaH)(dpp)(H2O)]n (2, dpp = 1,2-di(4-pyridyl)propane) manifests a 1D + 1D → 3D interlocked system of loop-containing perpendicular ribbon motifs. {[Cd4(tca)2(Htca)(bpmp)5(H2O)2]·27H2O}n (3, bpmp = bis(4-pyridylmethyl)piperazine) has intersecting [Cd4(tca)2(Htca)(H2O)2]n layer, [Cd(bpmp)(H2O)]n chain, and [Cd2(bpmp)3]n ladder submotifs and forms a complicated 3,4,5-connected trinodal 3D self-penetrated network with (6.92)(42638)(42638.9310) topology. {[Cd(tcaH)(Hbpmp)](ClO4)·5.5H2O}n (4) exhibits stacked cationic bilayer (4,4) grid slabs. All compounds showed potential as potential detectors for nitrobenzene in ethanol suspension via luminescence quenching, with 1 showing the highest uptake of analyte.

Cadmium and cobalt oxybis(benzoate) coordination polymers with diverse topologies depending on dipyridylamide ligands including a new self-penetrated network

Hydrothermal reaction of cadmium or cobalt nitrate, oxybis(benzoic acid) (obaH2), and a hydrogen-bonding capable dipyridylamide ligand afforded four crystalline coordination polymers whose dimensionality depends critically on the coordination environment or dipyridylamide length. The four new phases were structurally characterized via single-crystal X-ray diffraction. {[Cd(obaH)2(3-pina)2]·2(3-pina)·2H2O}n (1, 3-pina=3-pyridylisonicotinamide) shows 1D chain motifs, while {[Co(oba)(3-pina)]·H2O}n (2) displays closely interdigitated 2D (4,4) grid layer motifs. The longer-spanning dipyridylamide ligand N,N′-(hexane-1,6-diyl)diisonicotinamide (hdin) afforded coordination polymers with more interesting self-penetrated or entangled 3D networks. [Cd(oba)(hdin)]n (3) manifests a unique 4,6-connected 3D self-penetrated network with {426272}(42687283} topology. [Co2(oba)2(hdin)]n (4) exhibits a {Co2(OCO)4} paddlewheel-dimer based 6-connected 3-fold interpenetrated jsm net with 510648 topology. Luminescent behavior in 1 and 3 is attributed to intra-ligand molecular orbital transitions. The new d10 phases were also surveyed for the ability to detect nitrobenzene in ethanol suspension. Thermal decomposition behavior is also discussed herein.

A novel 3D self-penetrating metal–organic framework with unprecedented 7-connectivity and entangled pattern

A novel (4,4,7)-connected 3D self-penetrating network with unprecedented 7-connectivity, has been constructed using 1,4-bis(2-methylbenzimidazol-1-ylmethyl) benzene and 3,3′,4,4′-Benzophenonetetracarboxylic acid as co-ligands. It represents an unusual self-penetrating pattern with the entanglements of nonequivalent 4- and 6-membered shortest rings.

Unusual self-penetrating and polycatenated coordination polymers based on the semi-rigid V-shaped ligand 4-(1-(4-(2H-tetrazol-5-yl)benzyl)-1H-pyrazol-3-yl)pyridine

Self-assembly of d10 metal salts with a semi-rigid V-shaped N-containing ligand affords two entangled coordination frameworks, namely [Zn2(bdc)1.5(tbpp)] (1) and [Cd(tbpp)2(H2O)]·H2O (2) (Htbpp=4-(1-(4-(2H-tetrazol-5-yl)benzyl)-1H-pyrazol-3-yl)pyridine, H2bdc=1,4-benzenedicarboxylate acid). Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, X-ray powder diffraction and TG analyses. Compound 1 is a (3,6)-connected 3D self-penetrating network with an unprecedented (4.62)(43.67.74.8) topology. Compound 2 is the first example of (2D→3D) parallel polycatenation of 44-sql net with double edges. Additionally, the photoluminescence properties of compounds 1 and 2 were studied.

Two novel eight-connected self-penetrating porous lanthanide–organic frameworks: structures, luminescence, and gas adsorption properties

Two novel luminescent three-dimensional coordination polymers [Eu2(tpphz)(oba)3]·nH2O (n = 5.5 for 1, n = 3.5 for 2; H2oba = 4,4′-dicarboxydiphenyl ether) have been hydrothermally synthesized by in situ generation of tetrapyrido[3,2-a:2′,3′-c:3′′,2′′-h:2′′′,3′′′-j]phenazine (tpphz) ligand from 2-(4-pyridine)-imidazo-[4,5-f]1,10-phenanthroline precursor. Both complexes are rare examples of eight-connected self-penetrating networks. The porous nature of the structures is further supported by gas adsorption measurements.

An unprecedented stable self-penetrating metal-organic framework with solvent-dependent luminescence properties

A fascinating 3D pillared-layer structure, namely [Cd3(bpea)2(trz)2(H2O)2]·DMF (1), has been isolated under hydrothermal condition by reaction of cadmium salt, biphenylethene-4,4′-dicarboxylic acid (bpea) and 1,2,4-triazole (Htrz). Compound 1 presents an unusual self-penetrating network displaying uninodal seven-connected {414·5·66} topology with trinuclear cadmium clusters as seven-connected nodes, which exhibited exceptional resistance to acid/base aqueous solutions. Furthermore, solvent-dependent luminescence properties of 1 were investigated, and the results showed that 1 could serve as a potential luminescent sensor in detecting traces of the target species, such as toluene and nitrobenzene.

Unique topological motifs in two Cd(ii)-coordination polymers: mutual-embedded 2D bilayers, 3D polythreaded structures, self-penetrated networks and 2D → 2D interpenetrated homochiral bilayers

Two unique entangled Cd(ii) coordination polymers have been modulated by flexible/semi-rigid mixed-ligand systems.

Coordination assemblies of seven metal-organic frameworks based on a bent connector: structural diversity and properties

Seven new coordination polymers, namely, [Zn(L)(bdc)]·2H2O (1), [Zn(L)(2-NH2-bdc)]·2H2O (2), [Zn(L)(bdc)]·1.75DMF·0.5H2O (3), [Zn(L)(oba)]·H2O (4), [Co(L)(oba)]·H2O (5), [Cd2(L)2(bdc)(NO3)2]·2DMF (6) and [Cd(L)(ndc)(H2O)] (7) (L = 4-amino-3,5-bis(4-imidazol-1-ylphenyl)-1,2,4-triazole, H2bdc = 1,4-benzenedicarboxylic acid, 2-NH2-H2bdc = 2-amino-1,4-benzenedicarboxylic acid, H2oba = 4,4′-oxydibenzoic acid and H2ndc = 1,4-naphthalenedicarboxylic acid), have been synthesized. The structures were determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR, and thermogravimetric (TG) analysis. 1 and 2 feature a similar three-fold interpenetrating network combined with interdigitation which extends the structure into a three-dimensional framework. 3 is a two-fold interpenetrating framework showing intralayer porosity and interdigitation. Compounds 1 and 3 represent a pair of supramolecular isomers where structural motifs and different interpenetration modes exist; compounds 4 and 5 are isostructural and display the same three-fold interpenetrating framework where two types of interlaced triple-stranded helices A and B can be found. The triple-stranded helices with opposite chirality for each type are distributed in adjacent layers. Compound 6 exhibiting a unique simultaneous threading fashion of adjacent polymeric motifs gives the novel (2D → 3D) polythreaded array where coordinated NO3− anions act as the dangling ligands. Compound 7 is a 6-connected 3D self-penetrating network where right- and left-handed single-stranded helical chains (AR and AL) and interlaced triple-stranded helices (BR and BL) coexist. The luminescence properties of compounds 1–7 were also measured and discussed.

A cadmium oxybisbenzoate/pyridylnicotinamide coordination polymer with a new 8-connected self-penetrated topology

Crystals of {[Cd(oba)(4-pna)]·0.25H2O}n (1, oba=oxybisbenzoate, 4-pna=4-pyridylnicotinamide) were prepared by hydrothermal methods. A single-crystal structure determination showed the presence of two-fold interpenetrated [Cd2(oba)2]n dimer-based (4,4) layers, featuring embedded {Cd2O2} dimers that serve as 4-connected nodes. In turn these layers are connected by the dipodal 4-pna ligands into a [Cd(oba)(4-pna)]n 3-D coordination polymer network. Including these connections, the {Cd2O2} dimers can be considered as 8-connected nodes; these build a new but simple self-penetrated network with a 42464 topology substantially different from a standard body centered cubic bcu net. Luminescent and thermal properties of 1 are also reported.

Influence of geometric isomerism within dipyridylamide coligands on topology of copper adipate coordination polymers, including a new simple self-penetrated network

Hydrothermal reactions of a divalent copper salt, adipic acid (H2adp), and a dipyridylamide coligand have afforded four new crystalline coordination polymer solids, whose topologies depend critically on the specific dipyridylamide geometric isomer. [Cu(adp)(3-pina)]n (1, 3-pina=3-pyridylisonicotinamide) has a standard (4,4) grid layer topology, while {[Cu(adp)(3-pna)]·2.5H2O}n (2, 3-pna=3-pyridylnicotinamide) possesses a dimer-based 3-D network with 658 cds topology. Use of 4-pyridylnicotinamide (4-pna) as coligand afforded {[Cu3(adp)3(4-pna)2]·2H2O}n (3), which manifests a unique binodal 4,6-connected self-penetrated (658)(44611) 3-D topology. {[Cu(adp)(4-pna)2]n (4) is a simple 1-D chain polymer, obtained as a minor product during the synthesis of 3. Thermal properties of these materials are also discussed, along with the variable temperature magnetic properties of 2 and 3.

Ligand configuration introduced into a 3D self-interpenetrated coordination polymer as visible-light-driven photocatalyst

The combination of 1,4-bis(imidazol-1-ylmethyl)benzene (BIYB) and anthraquinone-2,7-disulfonic acid (H2AQDA) ligands leads to a copper coordination polymer, namely, {[Cu(BIYB)2(AQDA)]·H2O}n (1). The cis-BIYB ligands link one unique Cu(II) atoms to give 1D double chains, but trans-BIYB connects the other Cu(II) centers to generate 2D (4,4)-layers. Each H2AQDA ligand acts as a μ2-bridging linking the double chains and (4,4)-layers to generate the 3D framework of 1. Cu(1) and Cu(2) can be viewed as 6- and 4-connected nodes, which lead to a (4,6)-connected self-penetrated network. Notably, complex 1 represents the rare example of coordination polymer-based visible-light-driven photocatalyst, and shows good degradation efficiency of organic dye.

Guest-Effected Spin-Crossover in a Novel Three-Dimensional Self-Penetrating Coordination Polymer with Permanent Porosity

Porous and nonporous 3D heterobimetallic coordination polymers based on the 1,4-di(pyridin-4-yl)benzene ligand (dpb), [Fe(dpb){Ag(CN)2}{Ag2(CN)3}]·nSolv (1·nSolv; nSolv = DMF·EtOH, 2DMF·MeCN) and [Fe(dpb)2{Ag(CN)2}2] (2), have been synthesized by diffusion technique, respectively. Single-crystal X-ray analysis shows that 1·nSolv consists of a 3D self-penetrating network with in-situ-generated [Ag2(CN)3](-) species and displays one of the largest volume values of porosity (299 Å(3) per iron atom) after desolvation for the Hoffman-like porous SCO coordination polymers to date. In contrast, nonporous compound 2 is composed of two independent interpenetrated 3D nets with in-situ-generated [Ag(dpb)(CN)2](-) species. Their significant distinctions of structural architectures lead to dramatically different magnetic properties: 1·nSolv displays two-step guest-effected SCO with hysteresis, whereas 2 presents characteristic paramagnetic behavior.

Construction of two interpenetrating coordination networks based on 4,4′-bis(1H-imidazol-1-yl-methyl)biphenyl and effect of carboxylic acids

To investigate the construction of interpenetrating coordination networks and the effect of ligands, [Zn(bimb)(bdc)]·H2O (1) and [Zn(bimb)(Hbtc)]·H2O (2) [bimb = 4,4′-bis(1H-imidazol-1-yl-methyl)biphenyl; H2bdc = 1,2-benzenedicarboxylic acid; H3btc = 1,3,5-benzenetricarboxylic acid] were hydrothermally synthesized and characterized by elemental analysis, IR spectra, Powder X-ray diffraction, and thermogravimetric analysis. Complex 1 shows a 3-D uoc type topology with twofold interpenetration. However, 2 exhibits a different 2-D self-penetrating network owing to hydrogen bonds of Hbtc between the two interpenetrating sql sheets, indicating that different carboxylic ligands could affect the interpenetration structures. Photoluminescence of bimb and the two complexes are also studied.

Tuning Different Kinds of Entangled Networks by Varying N-Donor Ligands: From Self-Penetrating to Multi-interpenetrating

Via hydrothermal synthesis, the self-assembly of Zn(II) ions and H2fum with four flexible N-donor ligands, bpp, bib, bix, and bmix, generated five interesting entanglement systems (H2fum = fumaric acid, bpp = 1,3-bi(4-pyridyl)propane, bib = 1,4-bis(N-imidazolyl)butane, bix = 1,4-bis(imidazol-1-ylmethyl)-benzene, bmix = 1,4-bis(2-methylimidazol-1-ylmethyl)-benzene): {[Zn(fum)(bpp)]·H2O}n (1), {[Zn(fum)0.5(bib)1.5(H2O)]·NO3·3H2O}n (2), {Zn(fum)(bib)}n (3), {[Zn2(fum)2(bix)2]·3H2O}n (4), and {[Zn(fum)(bmix)0.5]·0.5H2O}n (5). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra, X-ray powder diffraction (XRPD), and thermogravimetric (TG) analyses. Compound 1 exhibits a rare 3D self-penetrating network with an unprecedented (85·10) topology. Compound 2 features a normal mode of 4-fold diamondoid interpenetrating net. However, in compound 3, five diamond networks interweave to form an interpenetrated diamond framework in an “abnormal” [3 + 2] mode. Compound 4 crystallizes in the orthorhombic crystal system and chiral space group P212121, which can be defined as an unusual 4-fold [2 + 2] interpenetrated unc-c net. Compound 5 displays a 2-fold interpenetrated 3D network with the classical pcu topology. A comparison of all compounds demonstrates that the structural characteristics of flexible N-donor ligands play a great role in the assembly of such different frameworks. Moreover, the luminescent properties of compounds 1–5 in the solid state have also been investigated.

Solvent/Temperature and Dipyridyl Ligands Induced Diverse Coordination Polymers Based on 3-(2′,5′-Dicarboxylphenyl)pyridine

Eleven new multidimensional transition coordination polymers, [Cd2(dcpy)2(H2O)] (1), [Cd(dcpy)]·H2O (2), [Cd(dcpy)(H2O)1.5]·2H2O (3), [Cd(dcpy)(bipy)0.5(H2O)]·5H2O (4), [Cd2(dcpy)2(bipy)(H2O)3]·2.5H2O (5), [Cd2(dcpy)2(bipy)]·4H2O (6), [Cd(dcpy)(bpa)0.5]·2H2O (7), [Ni(dcpy)(H2O)2] (8), [Ni(dcpy)(bpe)0.5(H2O)]·3H2O (9), [Ni(dcpy)(bpe)0.5(H2O)]·0.5H2O (10), and [Ni(dcpy)(bpa)0.5(H2O)2]·H2O (11), have been synthesized by using a tritopic ligand 3-(2′,5′-dicarboxylphenyl)pyridine acid (H2dcpy) and three different N-donor ancillary ligands (bipy = 4,4′-bipyridine, bpe = 1,2-bi(4-pyridyl)ethene, and bpa = 1,2-bi(4-pyridyl)ethane) in different solvents and temperatures. 1 is a four-connected three-dimensional (3D) framework based on two kinds of Cd–O–Cd and Cd–(COO)–Cd chains. 2 shows also a four-connected 3D framework with one-dimensional (1D) channels formed by double left- and right-handed helical chains. 3 displays a 3D microporous framework composed of Cd2O3 as a secondary building unit (SBU) with a (4,6)-connected net. 4 is a two-dimensional (2D) layer based on Cd2O2 SBU and further stacks to generate a 3D supramolecular framework with open channels. 5 is a rare 3D homochiral microporous framework with left-handed helical chains. 6 presents the first (3,4,6)-connected 3D self-penetrating framework based on 1D metal–organic nanotubes (MONTs). 7 is a (3,4)-connected 3D microporous pillar-layer framework with 1D square channels filled by left- or right-handed helical water clusters chains. 8 is a 2D (3,6)-connected net based on Ni2 dimers. 9 shows a wavelike 2D stacked layer framework possessing two types of open channels. 10 is a structural isomer of 9, showing an intriguing (3,4)-connected self-penetrating network, while 11 exhibits a 2D (3,4)-connected layer. The effects of solvents, temperatures, metal cations, and the lengths and rigidness/flexibility of the dipyridyl ligand on the crystal architectures are discussed. The solid-state photoluminescence for 1–7 and the magnetic properties for 8 were also investigated. Gas adsorption studies for 9 shows a high selective adsorption of CO2 over N2.

CuII coordination polymers based on 5-methoxyisophthalate and flexible N-donor ligands: Structures and magnetic properties

Three CuII coordination polymers, {[Cu2(CH3O-ip)2(bmib)]}n (1), {[Cu2(CH3O-ip)2(bmib)2]}n (2) and {[Cu(CH3O-ip)(bbip)]∙2H2O}n (3) (CH3O-H2ip is 5-methoxyisophthalic acid, bmib is 1,4-bis(2-methylimidazol-1-yl)butane and bbip is 1,3-bis(1H-benzimidazolyl)propane), have been synthesized by hydrothermal methods. Complexes 1–3 were structurally characterized by elemental analysis, infrared (IR) spectra and X-ray single-crystal diffraction. Complex 1 shows a 3D six-connected self-penetrating network based on paddlewheel secondary building units. Complex 2 has a 3-fold interpenetrating 3D diamond framework. Complex 3 possesses a 1D tube-like chain. Thermo-gravimetric and magnetic properties of 1–3 were also investigated.

A high-connected self-penetrating network supported by pentanuclear cobalt(II) secondary building units

A 3D ten-connected self-penetrating network based on the pentacobalt(II) clusters, [Co5(1,4-ndc)4(OH)2(1,3-bix)2]n (1) (1,4-H2ndc=1,4-naphthalenedicarboxylic acid; 1,3-bix=1,3-bis(imidazol-1-ylmethyl)benzene), is synthesized and characterized. Topological analysis indicates that it has ile-364345362 network. The magnetic data reveals the dominant antiferromagnetic interactions between the Co(II) cations.