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It is well known that gas adsorption and separation are crucial processes in many industries, including oil refining, metallurgy, environmental protection, and medicine. Thus, it is vital to develop highly energy-efficient porous materials for the storage and separation of gases. Porous metal–organic frameworks (MOFs) are new-type functional crystalline materials and formed by metal ions/clusters and organic ligands with diverse and adjustable structures. Particularly, N-heterocyclic carboxylate-based MOFs offer significant potential in gas capture and separation since the ligands in MOFs may exhibit strong coordination ability and various coordination modes. Herein, this review focuses on the major research progress of N-heterocyclic carboxylate-based MOFs in the adsorption and separation of common gases. This work may help to construct other new porous MOFs and further understand the relationship between the structures of MOFs and gas sorption/separation. [ABSTRACT FROM AUTHOR]

The incorporation of functional groups into the cavity of discrete supramolecular coordination cages (SCCs) will bring unique functions and applications. Here, three dicarboxylate ligands (H2L1Cl, H2L2Cl and H2L3Cl) containing N‐heterocyclic carbene (NHC) precursors as linkers were introduced to construct SCCs by combining with two C3‐symmertic (CpZr)3(μ3‐O)(μ2‐OH)3 clusters as three‐connect vertices, resulted in a series of rugby‐like V2E3 (V=vertex, E=edge) type homoleptic cages (SCC‐1, SCC‐2 and SCC‐3). However, V4E6‐type tetrahedral cages (SCC‐4 and SCC‐5), incorporating six Au‐NHC moieties, were obtained when the corresponding NHC‐gold(I) functionalized ligands (H2L1Au, H2L2Au) were applied. For the first time, we present a trackable CpZr‐involved cage to cage conversion to generate a heteroleptic V2E3 cage (SCC‐6) from two homoleptic cages (SCC‐2 and SCC‐5) with different geometries of V2E3 and V4E6. The heteroleptic assembly SCC‐6 can also be formed upon a subcomponent displacement strategy. The structural transformation and reassembly processes were detected and monitored by 1H NMR spectroscopy and electrospray‐ionization mass spectrometry. The formation of heteroleptic assembly was further supported by single crystal X‐ray diffraction analysis. Moreover, homoleptic cage SCC‐2 possesses a trigonal bipyramidal cationic cavity allowing the encapsulation of a series of sulfonate anionic guests. [ABSTRACT FROM AUTHOR]

Three isostructural lanthanide metal–organic frameworks (Ln-MOFs), {[Ln(L)(H2O)2]·H2O}n (M-Ln, Ln = Eu/Tb/Dy), were prepared with a flexible 3,5-(4-carboxybenzyloxy) benzoic acid (H3L) ligand and lanthanide ions by a solvothermal method. M-Ln are two-dimensional (2D) grid layer-stacking frameworks. M-Eu exhibits excellent chemical stabilities against organic solvents and shows strong luminescence. The experimental results indicated that M-Eu could be used as an ideal fluorescent probe to detect nitrobenzene (NB) in different solvents with a lower detection limit. M-Eu can also be used as a pH sensor because of its superior water stability. Furthermore, M-Eu and M-Tb show unique strong luminescence properties with high absolute quantum yields. The quantum yields can even reach up to 11.8% and 60.5%, respectively. Simultaneously, various kinds of heterometallic doped M-Eu x Tb 1−x MOFs were acquired by tuning the ratios of Eu3+/Tb3+ ions, showing the unique color changes from red, orange-red, orange, orange-yellow, light yellow, yellow to green. [ABSTRACT FROM AUTHOR]

To develop efficient adsorbent materials for storage and separation of C2H2, an unprecedented supercage MOF, [Me2NH2]⋅[Zn3(ALP)(TDC)2.5]⋅3.5DMF⋅2 H2O (1) was constructed through medicinal molecule allopurinol (ALP) and S‐containing 2,5‐thiophenedicarboxylic acid (H2TDC). 1 contains a novel linear trinuclear cluster that is composed by ALP and carboxylates and forms a final uncommon 5‐connected yfy topological framework. The framework possesses three types of interlinked cages decorated by rich functional sites, and reveals not only high adsorption capacity for C2H2 but also excellent selective separation for C2H2/CO2 and C2H2/CH4 at 298 K. Dynamic breakthrough experiments on C2H2/CO2 (1:1) mixture and C2H2/CH4 (1:1) mixture also demonstrated the potential of the material to separate C2H2 from CO2 or CH4 mixtures. Molecular simulations were also studied to identify the different CO2‐ and C2H2‐ binding sites in 1, such as carboxylate groups, S atoms and carbonyl groups. [ABSTRACT FROM AUTHOR]

Controlling the size and surface functionalization of nanoparticles (NPs) can lead to improved properties and applicability. Herein, we demonstrate the efficiency of the metal‐carbene template approach (MCTA) to synthesize highly robust and soluble three‐dimensional polyimidazolium cages (PICs) of different sizes, each bearing numerous imidazolium groups, and use these as templates to synthesize and stabilize catalytically active, cavity‐hosted, dispersed poly‐N‐heterocyclic carbene (NHC)‐anchored gold NPs. Owing to the stabilization of the NHC ligands and the effective confinement of the cage cavities, the as‐prepared poly‐NHC‐shell‐encapsulated AuNPs displayed promising stability towards heat, pH, and chemical regents. Most notably, all the Au@PCCs (PCC=polycarbene cage) exhibited excellent catalytic activities in various chemical reactions, together with high stability and durability. [ABSTRACT FROM AUTHOR]

Metallosupramolecular poly‐NHC‐metal assemblies were prepared from trigonal hexakis (H6‐1 a(PF6)6 and H6‐1 b(PF6)6) or nonakis (H9‐3(BF4)9) imidazolium salts and Ag2O. Complexes [Ag6(1 a)2](PF6)6 and [Ag6(1 b)2](PF6)6 are built from six Ag+ ions sandwiched between two trigonal hexacarbene ligands with an inner and an outer NHC donor in each of the three ligand arms. The metal atoms are arranged in two triangles. The hexakis‐NHC ligands bear cinnamic ester groups at the outlying NHC donors, used in postsynthetic [2+2] cycloaddition reactions linking two hexakis‐NHC ligands by three cyclobutane units to give complexes [Ag6(2 a)](PF6)6 and [Ag6(2 b)](PF6)6 bearing a dodecacarbene ligand. From the related nonakisimidazolium salt H9‐3(BF4)9, complex [Ag9(4)](BF4)9 bearing an octadecacarbene ligand was obtained. Removal of the template metals yielded very large, stable, polyimidazolium cations with 12 or 18 internal imidazolium groups. [ABSTRACT FROM AUTHOR]

To better understand the factors determining the multi-step relaxation processes in polynuclear lanthanide single molecule magnets (SMMs), two Dy(iii)4 SMMs showing two-step relaxation processes were elaborately designed and investigated for their structure-dependent magnetic properties. Through targetedly fine-tuning the auxiliary ligand (from the anion of 1-phenylbutane-1,3-dione to 2-acetylcyclopentanone) on specific Dy(iii) sites while retaining the same type of coordination atoms, one of the two relaxation processes shifted to higher temperature with an increase of energy barrier, which permits the unambiguous assignment of the relaxation processes to specific metal sites. Therefore, the present {Dy4} systems provide a good example to probe the factors determining the relaxation dynamics, and point to a simple way to optimize the magnetic performance of polynuclear dysprosium SMMs. [ABSTRACT FROM AUTHOR]

Based on various comparable salen ligands, three synthesized CuIINaI-complexes present efficient catalytic activities for the coupling and cyclization reaction of 1,2-diaminopropane with nitriles towards 2-imidazolines. The catalytic results show that salen ligands with an electron-donating substituent and small steric hindrance improve the catalytic activity. [ABSTRACT FROM AUTHOR]

The metal‐controlled self‐assembly of organometallic molecular cylinders from a series of imidazo[1,5‐a]pyridine‐based tris‐NHC ligands is described in this report. The imidazo[1,5‐a]pyridinium salts H3‐L(PF6)3 (L=4 a–4 c) were treated with 1.5 equivalents of Ag2O to yield the trinuclear AgI hexacarbene cages [Ag3(L)2](PF6)3 (L=4 a–4 c), in which three AgI are sandwiched between the two tricarbene ligands. The silver(I) complexes [Ag3(L)2](PF6)3 underwent a facile transmetalation reaction in the presence of 3 equivalents of [AuCl(tht)] (tht=tetrahydrothiophene) to furnish the trinuclear AuI cylinder‐like cages [Au3(L)2](PF6)3 (L=4 a–4 c) without destruction of the metallosupramolecular structure. The new hexacarbene assemblies feature a large cavity that can easily accommodate a molecule of dimethyl sulfoxide as molecular guest. This is the first study of a unique "host–guest" system containing an organometallic cylinder‐like cage derived exclusively from poly‐NHC ligands. Well done imidazopyridine! A set of novel organometallic molecular cylinders comprising imidazo[1,5‐a]pyridine‐based tris‐NHC ligands is described. The incorporation of imidazo[1,5‐a]pyridine scaffolds into the poly‐NHC ligands enhances the cavity size of the new trinuclear metallacages prepared by a silver‐ and gold‐mediated self‐assembly strategy. The metallacages have potential in molecular recognition (see figure). [ABSTRACT FROM AUTHOR]

A lead carboxylate–azolate framework, [Pb3(μ4‐O)(L)2(H2O)] ⋅ 2H2O (1), has been constructed from the reaction of 2‐methyl‐4‐(1H‐tetrazol‐5‐yl) benzoic acid (H2L) and Pb(NO3)2 under solvothermal conditions. Compound 1 contains an unprecedented hexanuclear cluster [Pb6(μ4‐O)2(COO)4(CN4)2], which as an 8‐connected node is connected by 3‐connected L linkers to give rise to a three‐dimensional framework with an uncommon (3,8)‐connected tfz‐d; UO3 topology. Framework 1 possesses strong solid‐state yellow luminescence (563 nm), which stems from ligand‐to‐metal charge transfer (LMCT), however, the removal of water molecules in 1 lead to the significant luminescent decrease of the sample. Importantly, in the presence of 1, the thermal decomposition of ammonium perchlorate is significantly accelerated. MOFs make things faster: A metal‐organic framework (MOF) based on hexanuclear [Pb6(μ4‐O)2(COO)4(CN4)2] clusters was prepared by using a 2‐methyl‐4‐(1H‐tetrazol‐5‐yl) benzoic acid ligand. The MOF has a (3,8)‐connected tfz‐d; UO3 topology, and undergoes luminescence changes caused by the removal of water. It also accelerates the thermal decomposition of ammonium perchlorate. [ABSTRACT FROM AUTHOR]

The reactions of an unexploited N,N′‐5‐carboxyl‐1,3‐phenylenebis(ethyl oxamate) (HEt2L) ligand with different Mn2+ and Cd2+ salts under solvothermal conditions afforded four three‐dimensional (3D) coordination polymers (CPs): [Mn1.5L(H2O)2]⋅H2O (1) [Mn2L(C2O4)0.5(NMP)(H2O)] ⋅ NMP (2), [Cd1.5L(H2O)2.5] ⋅ H2O (3) and [Cd2L(C2O4)0.5(H2O)3] ⋅ H2O (4) (NMP=N‐methyl pyrrolidone). L, generated by the in‐situ hydrolysis of HEt2L, displays four kinds of coordinating modes through oxamate and carboxylate groups as well as different syn‐syn and syn‐trans configurations. The resulting novel (3,4,5)‐, (3,4,6)‐, (4,5)‐ and (4,4,4,5)‐connected topologies for 1–4 were formed. Among them, 1 has interesting 1D metal‐oxamate zigzag chains, 2 contains 1D channels with a free void of 52.5 %, 3 consists of an unprecedented Cd‐oxamate layer, 4 has a novel Cd‐oxamate‐oxalate chain. The antiferromagnetic interactions of 1 and 2 were observed, meanwhile 3 and 4 exhibit solid‐state luminescence with the maximum emission bands at 483 and 479 nm, respectively, under an excitation of 332 nm. Structural Diversity: Four novel coordination polymers (CP) were constructed by Mn2+ and Cd2+ ions with N,N′‐5‐carboxyl‐1,3‐phenylenebis (oxamic acid), showing framework diversity caused by various ligand coordinating modes (See figure). In addition, antiferromagnetic interactions and exhibit solid‐state luminescence properties were investigated. [ABSTRACT FROM AUTHOR]

Homoleptic and heteroleptic cylinder‐shaped poly‐NHC metallosupramolecular assemblies [Ag3(L)2](BF4)3 have been prepared by control of the shape, size, and electronic properties of disk‐shaped trisimidazolium salts of type H3‐L(BF4)3. Both imidazolium salts with an electron‐deficient triazine backbone H3‐A(BF4)3 or an electron‐rich benzene backbone H3‐D(BF4)3 have been employed. Reaction of H3‐A(BF4)3 or H3‐D(BF4)3 with Ag2O yield trinuclear homoligand complexes [Ag3(L)2](BF4)3 (L=A, D). However, equimolar mixtures of H3‐A(BF4)3 and H3‐D(BF4)3 react with Ag2O under social self‐sorting to give the heteroligand assembly [Ag3(A)(D)](BF4)3. The same heteroligand assembly was obtained by transmetallation from mixtures of complexes [Ag3(A)2](BF4)3 and [Ag3(D)2](BF4)3. The transmetallation from [Ag3(A)(D)](BF4)3 to [Au3(A)(D)](BF4)3 is also demonstrated. The study expands to concepts of narcissistic and social self‐sorting from classical Werner‐type ligands to organometallic NHC chemistry thereby opening new routes for the construction of poly‐NHC metal assemblies with increasing complexity. Unprecedented social self‐sorting occurs during the reaction of Ag2O with two trisimidazolium salts featuring either an electron‐poor H3‐A1(BF4)3 or an electron‐rich H3‐D1(BF4)3 backbone to give the heteroligand assembly [Ag3(A1)(D1)](BF4)3 most likely driven by π⋅⋅⋅π stacking interactions between the electron‐rich and electron‐poor ligand backbone groups. [ABSTRACT FROM AUTHOR]

Using a triazole carboxylic ligand (H2L = 4-(1H-1,2,4-triazol-1-yl) isophthalic acid), four water-stable lanthanide metal-organic frameworks (Ln(III)-MOFs) (1-Ln, Ln(III) = Tb, Eu, Dy, and Sm), [Ln(L)(HL)(H2O)2], where the deprotonated H2L ligands have two different coordination modes: L2− and HL− [(a): η2μ2χ2, η2μ1χ2; (b): η2μ1χ2], have been synthesized by solvothermal reaction and characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analyses show that Ln(III)-MOFs are isostructural with 2D-layered structures with uncoordinated carboxylic and triazole groups. The luminescent properties of 1-Tb in aqueous solution containing different cationic solutions and small organic solvents have been explored under ultraviolet irradiation at room temperature. The high quenching constant KSV values and low detection limits indicate that 1-Tb exhibits extremely high detection sensitivity and selectivity toward Fe3+ ions and nitrobenzene; 1-Tb can keep its original network and be reused after the sensing experiments, which provide us with an optical material for detecting Fe3+ ions and nitrobenzene. Magnetic studies show that antiferromagnetic exchange interactions exist between Dy(III) ions in 1-Dy. [ABSTRACT FROM AUTHOR]

Abstract: An anion‐coordination‐based A4L6 (“A” denotes anion and “L” is ligand) tetrahedral cage was constructed by a C2‐symmetric bis‐bis(urea) ligand and phosphate anion, which showed reversible interconversion with the A2L3 triple helicate as a response to the template, concentration, or solvent. Notably, an unusual “peripheral” templation was found to be critical to stabilize the tetrahedral structure. This peripheral effect was utilized to assemble an “empty” A4L6 cage that allows the multi‐stimuli‐controlled capture/release of biologically important species such as choline and acetylcholine. [ABSTRACT FROM AUTHOR]

Five coordination polymers, {[Zn(dtp)]·H2O} (1), {[Zn(dtp)]·2CH3OH·NMP} (2), {[Mn2(dtp)2(H2O)4]·12(H2O)} (3), {[Mn(Hdtp)(Cl)]} (4) and {[Mn(dtp)(H2O)]·1.5H2O} (5) with different dimensional structures, have been solvothermally synthesized by utilizing the H2dtp ligand (H2dtp = 4′-(3,-5-dicarboxyphenyl)-2,2′:6′,2′′-terpyridine). All complexes are characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD). The Zn(ii)-based complexes 1 and 2 display a 2D wavy layer structure and a 3D porous framework with a 1D channel, respectively. The three Mn(ii)-based complexes 3–5 exhibit two 1D chain and one 2D layer structures, respectively. Complexes 1 and 2 reveal their luminescence properties, whereas complexes 3–5 display an antiferromagnetic exchange. Meanwhile, an unusual stepwise adsorption for CO2 was also observed in 2. [ABSTRACT FROM AUTHOR]

In search of lanthanide single-molecule magnets, a novel dinuclear dysprosium complex, namely [Dy 2 (L) 2 (DBM) 2 (DMF) 2 ]·3CH 3 OH ( 1 ) (H 2 L = 2-((2-hydroxy-3-methoxybenzylidene)amino)acetic acid, HDBM = dibenzoylmethane), was synthesized, structurally and magnetically characterized. Single-crystal X-ray structural analysis reveals that the key feature of 1 is neutral dinuclear complex, in which two Dy(III) ions with eight-coordinated environment are bridged by two phenoxido oxygen atoms of two o -vanillin Schiff base ligands. Electrospray ionization mass spectrometry (ESI-MS) results revealed that the intact framework of complex 1 stable in methanol solution. Its magnetic susceptibilities to an alternating current revealed that complex 1 exhibits single-molecule magnet behaviour. [ABSTRACT FROM AUTHOR]

A new zinc(II) coordination polymer, namely [Zn(bipy)2(H2O)4]n·n(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 P21/c space group. The unit cell constants of complex 1 are a = 9.2579 Å, b = 12.2016 Å, c = 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. [ABSTRACT FROM AUTHOR]

By using an asymmetrical rigid pentacarboxylic acid ligand, 2,4-di(3′,5′-dicarboxylphenyl)benzoic acid (H5L), four new three-dimensional (3D) metal–organic frameworks (MOFs), namely {[Cu2(HL)(H2O)2]·2DMF·2H2O}n (1), {[Co2(L)(DMA)]·H2N(Me)2}n (2), {[Co2(L)(H2O)]·H2N(Me)2}n (3), {[Mn2(L)(DMF)(H2O)]·H2N(Me)2}n (4), were solvothermally synthesized. H5L in 1–4 shows different coordination modes and can easily form various metal clusters (secondary building units, SBUs) in the final structures. 1 is a 3D porous framework with a (4,4)-connected pts topology based on the [Cu2(COO)4] paddlewheel SBU, wherein six SBUs are connected by twelve HL4− to get an unprecedented Cu12 hendecahedron nanocage. 2–4 possess similar dinuclear [M2(COO)5] SBUs (M = Co, Mn), which are further extended by L5− to give rise to 3D frameworks with the uncommon (5,5)-connected nia-5,5-P21/c and bnn topologies. In addition, the desolvated framework of 1 contains polar channels decorated with uncoordinated carboxylate groups, leading to selective adsorption for CO2 over CH4 at 195, 273 and 298 K. Moreover, the magnetic properties of 1–4 show that there exist antiferromagnetic interactions between metal ions. [ABSTRACT FROM AUTHOR]

Due to the high bond dissociation energy, low proton acidity, and highly nonpolar character of the C–C bond, activation or cleavage of the bonds, especially the C(sp2)–C(sp2) σ bond, is one of the most challenging tasks in synthetic chemistry. Herein, we present a simple and effective strategy for cleavage of the C(sp2)–C(sp2) σ bond between two phenyl groups under mild reaction conditions during the construction of zinc(ii) organic frameworks. By reacting the organic ligand 3-(2′,5′-dicarboxyphenyl)benzoic acid (H3dbba) and 1,2-bis(4-pyridyl)ethane (bpe) with Zn(ii) ions in dimethylformamide, dimethylacetamide, or diethylformamide solvent systems, complete cleavage of the C(sp2)–C(sp2) σ bonds between two phenyl groups occurred and all H3dbba ligands were broken into 1,4-benzenedicarboxylate (bdc) and benzoic acid, and a new coordination polymer, [Zn(bdc)(bpe)] was obtained. We discuss a plausible mechanism for this cleavage mode and confirm that it occurred. This extraordinary example of C(sp2)–C(sp2) σ bond cleavage under mild conditions provides new insights for both organic and inorganic synthetic chemistry. [ABSTRACT FROM AUTHOR]

A coordination polymer, [Pb2(OH)(tzia)]·2H2O (1), has been prepared by solvothermal reaction of 5-(1H-tetrazol-5-yl)isophthalic acid (H3tzia) and Pb(NO3)2. The polymer1is based on an unprecedented centrosymmetric tetranuclear [Pb4(OH)2(COO)4(ttaz)2] cluster linked by a multidentate tzia ligand, affording a 2-D 3,6-connectedkgdlayer. The adjacent layers are further jointed by Pb⋯O interactions to form a 3-D supramolecular framework with a rare (3,8)-connectedtfz-d; UO3topology. Photoluminescent properties of H3tzia,1, and1-desolvated have been further investigated, and it was interesting to find that1-desolvated due to the removal of lattice water molecules reveals stronger photoluminescence than1. [ABSTRACT FROM PUBLISHER]

In this report, seven new luminescent metal–organic frameworks (LMOFs), [Zn(L)0.5(H2O)2]·H2O (1), [Zn(L)0.5(DMF)] (2), [Zn3(L)(μ3-OH)2(H2O)4] (3), [Zn2(L)(DMA)(H2O)]·5(H2O) (4), [Cd(L)]·2(H3O)·(H2O) (5), [Cd2(L)(H2O)3] (6), and [Pb(L)0.5(H2O)] (7) (H4L = [1,1′:4′,1′′-terphenyl]-2′,3,3′′,5′-tetracarboxylic acid; DMF = N,N-dimethylformamide; DMA = N,N-dimethylacetamide) have been solvothermally synthesized by using Zn(ii), Cd(ii), Pb(ii) ions and H4L in different solvent systems, all of which have been routinely characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analyses show the different dimensionalities (1D, 2D or 3D) of complexes 1–7. Comparative structural studies of 1–7 reveal that the L4− ligands adopt different coordination morphologies: 1 (η1μ1χ1), 2 (η2μ2χ2), 3 (η2μ2χ2), 4 (η2μ2χ2; η1μ1χ1), 5 (η2μ1χ2), 6 (η2μ2χ2; η2μ2χ3), and 7 (η2μ2χ2; η2μ3χ4) with Zn(ii) (74 pm), Cd(ii) (97 pm) and Pb(ii) (119 pm) in different solvent systems, which produce the complexes with different frameworks. Complex 1 displays a 1D dimeric chain. Complexes 2 and 5 present a 2D layer structure with a uninodal 4-connected sql net with a symbol of (44·62). Complexes 3, 6 and 7 have a 3D dense packing structure based on infinite 1D rod-like secondary building units (SBUs). Complex 3 is designated as a binodal (4, 6)-connected fry topological net with the point symbol (510·63·78)(54·62). The whole network of 6 can be simplified as a binodal (4, 8)-connected flu topological net with a point symbol of (412·612·84)(46)2. Complex 7 can be seen as a new binodal (5, 10)-connected topological net with the point symbol (410)2(428·616·8). Complex 4 shows a 3D framework based on a binuclear [Zn2(CO)3O3] SBU, which can be viewed as a uninodal 4-connected sra topological net with the point symbol (42·63·8). Further, the solid-state luminescence properties of the complexes were measured and studied intensively at room temperature. [ABSTRACT FROM AUTHOR]

By treating a semirigid 5-oxyacetate isophthalic acid (H3OAIP) ligand with MnSO4/CoSO4/CdSO4 under solvothermal conditions, three isostructural cluster organic frameworks, [M2(OH)(OAIP)(DMA)] ⋅H2O (M=Mn2+ ( 1), Co2+ ( 2), Cd2+ ( 3); DMA= N,N′-dimethylacetamide) were constructed. The three complexes contain novel eight-connected tetranuclear M4(OH)2(COO)6(OCH2COO)2 clusters with the unique hexagonal bipyramidal configuration, which are extended by four-connected OAIP linkers to form an uncommon (4,8)-connected alb-4,8-Cmce topology based on (3,6)-connected kgd sublayers. Both 1 and 2 showed significant antiferromagnetic interactions between the intracluster metal ions, whereas 3 revealed strong blue photoluminescence. [ABSTRACT FROM AUTHOR]

Four heteroditopic macrocyclic ligands incorporating both anion coordination sites (tris-urea units) and a cation binding fragment (polyether) were designed for possible application in molecular devices. Sandwich-type phosphate complexes were formed, which display a reversible rotation around the anion upon protonation/deprotonation of phosphate and binding of the cation (Emim+). [ABSTRACT FROM AUTHOR]

Reaction-determined assemblies of 6,6′-dinitrobiphenyl-2,2′,4,4′-tetracarboxylic acid (H4nbtc), various N-donor ligands and transition metal ions produce ten complexes, namely, [Zn2(nbtc)(bpa)·H2O]n (1), [Zn2(nbtc)(bpe)·H2O]n (2), [Zn2(nbtc)(2,2′-dpy)]n (3), Zn(H3nbtc)(phen)2 (4), {(H3O)2[Cd3(nbtc)2(H2O)3]·5H2O}n (5), [Cd2(nbtc)(ndpy)·0.5H2O]n (6), [Ag2(H2nbtc)(bpp)]n (7), [Co2(nbtc)(phen)2(H2O)2]n (8), [Ni2(nbtc)(phen)2(H2O)2]n (9) and Co(H2nbtc)(phen)2·2H2O (10) (bpa = 1,2-bis(4-pyridyl)ethane, bpe = 1,2-di(4-pyridyl)ethylene, bpp = 1,3-bis(4-pyridyl)propane, 2,2′-dpy = 2,2′-dipyridyl, phen = 1,10-phenanthroline, ndpy = 2-pyridinamine). Isostructural 1 and 2 feature 3D “bilayered-pillared” frameworks constructed from Zn2(μ2-COO)2(μ1-COO)2-nbtc4− wave-bilayers and bpa/bpe pillars. Unlike 1 and 2, both 3 and 6 exhibit 3D “brick-wall” frameworks constructed from nbtc4− and various SBUs (0D Zn2(μ2-COO)3(μ1-COO)1 for 3, 1D [Cd2(μ2-COO)4]n for 6). However, 3D 5 can be viewed as a combination of 2D “brick-wall” layers and 1D [Cd3-nbtc] chains. Moreover, in comparison to neutral 3 and 6 with pensile and cosmetic terminal ligands, complex 5 without an N-donor ligand is particularly interesting, containing two hydronium ions to balance the anion unit [Cd3(nbtc)2(H2O)3]2− as well as three types of coordinated Cd(ii) ions (6-, 7- and 8-). Unlike 3, complex 4 is mononuclear, despite the two complexes employing similar terminal ligands (2,2′-dpy for 3, phen for 4). In 2D layered Ag(i) 7, the 0D Ag4(μ2-COO)4 SBUs initially form Ag4(μ2-COO)4-H2nbtc2− chains before being bridged by bpp ligands. Isostructural Co(ii) 8 and Ni(ii) 9 exhibit 1D looped infinite chains. Structural comparisons indicate that the SBUs, the coordination modes of the H4nbtc ligand, the synthetic conditions and the nature of the N-donor ligands are crucial factors with respect to the structures of these compounds. Furthermore, the luminescence properties of 1–7 were investigated in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Seven new mixed–ligand coordination polymers, {[Co0.5(bib)0.5(tftpa)0.5]·0.5H2O}n (1), [Cd2(bib)(tftpa)2]n (2), [Ni0.5(bib)0.5(tftpa)0.5]n (3), {[Co0.5(tftpa)(H2O)]·0.5bib·EtOH}n (4), {[Cd0.5(tftpa)(H2O)]·0.5bib·EtOH}n (5), [Cd3(bib)3(tftpa)3(MeOH)3]n (6), and [Cd(bib)(tftpa)(MeOH)]n (7) (bib = 1,4-bis(2-methylimidazol-1-yl)butane, H2tftpa = tetrafluoroterephthalic acid) have been synthesized under different reaction conditions and characterized by elemental analysis, IR, PXRD, single crystal X-ray diffraction analysis and thermogravimetric analysis. Complex 1 exhibits an unusual [2 + 2] interpenetrating diamond framework belonging to class IIIa with the point symbol 66. Complex 2 reveals a (3,4)-connected 3D framework with a unique double-stranded helical chain based on Cd–O–Cd and Cd–(COO)–Cd. Complex 3 presents a 4-fold interpenetrating 3D diamond framework belonging to class Ia with the point symbol 66. Complexes 4 and 5 display a 3D supramolecular architecture built on 2D stacked layers through hydrogen bonding and π–π interactions. Complex 6 also shows a 3D 4-fold interpenetrating diamond framework belonging to class Ia with the point symbol 66. Complex 7 features a 2D + 2D → 2D parallel polycatenated framework with the point symbol 44·62. The structural diversity of complexes 1–7 illustrate that a subtle change can have a marked effect on the crystal architectures. Moreover, the magnetic properties of complexes 1, 3, and 4, and the solid-state photoluminescence results for complexes 2, and 5–7 were also studied. [ABSTRACT FROM AUTHOR]

The reaction of N-rich pyrazinyl triazolyl carboxyl ligand 3-(4-carboxylbenzene)-5-(2-pyrazinyl)-1 H-1,2,4-triazole (H2cbptz) with MnCl2 afforded 3D cationic metal-organic framework (MOF) [Mn2(Hcbptz)2(Cl)(H2O)]Cl ⋅DMF ⋅0.5 CH3CN ( 1), which has an unusual (3,4)-connected 3,4T1 topology and 1D channels composed of cavities. MOF 1 has a very polar framework that contains exposed metal sites, uncoordinated N atoms, narrow channels, and Cl− basic sites, which lead to not only high CO2 uptake, but also remarkably selective adsorption of CO2 over N2 and CH4 at 298-333 K. The multiple CO2-philic sites were identified by grand canonical Monte Carlo simulations. Moreover, 1 shows excellent stability in natural air environment. These advantages make 1 a very promising candidate in post-combustion CO2 capture, natural-gas upgrading, and landfill gas-purification processes. [ABSTRACT FROM AUTHOR]

Six new Co(ii)-based mixed-ligand coordination polymers, namely, [Co2(H3bppc)2(2,2′-bpy)4]·H2O (1), [Co2(Hbppc)(2,2′-bpy)2(H2O)]·H2O (2), [Co(H2bppc)(H-bpp)]·2H2O (3), [Co3(μ3-OH)(bppc)(dps)(CH3CH2OH)]·4H2O (4), [Co2(bppc)(bib)(H2O)4]·(H2-bib)0.5·(H2O)3 (5), and [Co2(Hbppc)(bix)2]·2H2O (6), (H5bppc = biphenyl-2,4,6,3′,5′-pentacarboxylic acid, 2,2′-bpy = 2,2′-bipyridine, bpp = 1,3-bis(4-pyridyl)propane, dps = 4,4′-sulfanediyldipyridine, bib = 1,4-bis(imidazol-1-yl)benzene, bix = 1,4-bis(imidazol-1-ylmethyl)benzene), have been obtained under solvothermal conditions. 1 exhibits a 3D supramolecular framework based on a [Co2(H3bppc)2(2,2′-bpy)4] unit. 2 has a (3,4)-connected dmc net with a (4·82)(4·85) topology containing alternate binuclear metal clusters and single metal centres. 3 shows a 3D supramolecular architecture constructed from ladder-like arrays decorated with H-bpp. 4 exhibits a binodal (5,7)-connected 3D network based on trinuclear [Co3(μ3-OH)]5+ units with an unusual (3·46·52·6)(32·46·57·65·7) topology. 5 features a (4,6)-connected 3D fsc open framework with binuclear [Co2(H2O)(COO)]3+ units as nodes, and H2-bib and water molecules located in the voids of its framework by hydrogen bonds. 6 possesses a 3D net containing unusual 2D polyrotaxane sheets. Topological analysis reveals that 6 has a (3,4,4)-connected 3D network with a (4·6·74)(4·6·7)(6·72·102·11) topology. The structural difference of 1 and 2 is due to the different pH values of the reaction system. Though complexes 2–6 were synthesised under similar reaction conditions, the carboxylic groups of H5bppc were partially deprotonated in 2, 3 and 6 and fully deprotonated in 4 and 5. Complexes 2–6 display diverse structures depending on different N-donor ligands and the coordination modes of the multicarboxylate ligand. Variable-temperature magnetic susceptibility measurements reveal that complexes 1–6 show antiferromagnetic interactions. [ABSTRACT FROM AUTHOR]

In this article, it has used four rigid bidentate N-donor ligands (phen = phenanthroline, 2,2′-bipy = 2,2′-bipyridine, 4,4′-bipy = 4,4′-bipyridine, bpe = 1,2-bis(4-pyridyl)ethene) reacted with the Cd(II) ions and flexible ligand 4,4′-((5-carboxy-1,3-phenylene)bis(oxy))dibenzoic acid (H 3 cpbda), and successfully synthesized five complexes with different dimensions and luminescence properties. In addition to the “T” and “Y” shaped molecular configurations of H 3 cpbda, the “M” shaped molecular configuration is found for the first time. Three types of molecular configurations act various roles to assemble different dimensional structures. Furthermore, the influence of two different kinds of rigid bidentate N-donor ligands on dimensions and luminescence properties has been studied. [ABSTRACT FROM AUTHOR]

Three new Cd(ii)-MOFs, [Cd(L1)0.5(bpp)] (1), [Cd(L1)0.5(bipy)] (2), and [Cd(L2)0.5(bipy)] (3) [H4Ln = (1,1′:4′,1′′-terphenyl)-2′,x,x′′,5′-tetracarboxylic acid (n = 1, x = 3, and n = 2, x = 4), bpp = 1,3-di(4-pyridyl)propane, and bipy = 2,2′-bipyridine], have been synthesized using Cd(ii) ions and isomeric H4Ln ligands in the presence of auxiliary ligands via solvothermal reaction, and have been fully characterized by elemental analysis, FT-IR spectroscopy, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Complex 1 is a three-dimensional (3D) pillar-layered network built from L14− and bridging bpp co-ligands with a binodal (4,8)-connected gsp2 topology and a symbol of (44·62)(416·612). 2 was successfully synthesized using bipy instead of the bpp ligand used to assemble 1 giving a 2D 4-connected sql net. 3 is a 3D reticular framework with [Cd2(COO)4] SBUs based on L24− ligands, displaying a (4,4)-connected lvt (42·84) topology. X-ray diffraction analysis revealed that the structures of the MOFs can be mediated by the steric effect of the tetracarboxylate and secondary co-ligands. The solid-state luminescence properties of the MOFs were measured carefully by ultraviolet irradiation at room temperature. In particular, 3 exhibited a high sensitivity for Fe3+ in aqueous solutions of mixed metal ions, which makes it a promising crystalline material to be a luminescent probe for Fe3+. Importantly, 3 can keep its original framework and be reused in sensing experiments. The sensing mechanism has also been studied in detail. [ABSTRACT FROM AUTHOR]

Four uncommon isostructural nanocage-based 3D Ln-MOFs, 1-Ln (Ln = Eu, Tb, Gd and Dy), were constructed using a new diisophthalate ligand with active pyridyl sites. 1-Eu exhibits highly efficient luminescent sensing for Cu2+ ions and selective CO2 capture. [ABSTRACT FROM AUTHOR]

Four new coordination polymers (CPs), [Co3(L)2(bib)3(EtOH)2]·2H2O (1), [Mn3(L)2(bib)2(H2O)4]·4H2O (2), [Ni(HL)(bib)(H2O)3] (3) and [Ni3(bib)4(H2O)10]·2(L)·12(H2O) (4), were synthesized under solvothermal conditions with an unsymmetrical tricarboxylic acid ligand [biphenyl-3,3',5-tricarboxylic acid (H3L)] in the presence of the 1,4-bis(1H-imidazol-4-yl)benzene (bib) ligand. In compound 1, tricarboxylate acid ligands (H3L) link Co centers to generate two-dimensional (2D) layers which are further connected by bib ligands to exhibit a three-dimensional (3D) framework with a (4,4,5)-connected (4²·6³·8)2(4²·67·8)2(64·8·10) topology. The three-dimensional (3D) framework of 2 is defined as a (3,3,4)-connected topology with the point symbol of (6·8²)2(6²·8)2(8·104·12). Compound 3 contains a one-dimensional (1D) left-hand helix chain along the a direction and further extends into a 2D supramolecular network and a 3D supramolecular framework via hydrogen bonds. Compound 4 displays a one-dimensional (1D) molecular ladder, which is further combined with each other through π...π stacking to extend into 2D supramolecular sheets. The supramolecular networks of 3 and 4 resulted from the different solvent ratios [V(H2O)-V(EtOH)] in the reaction. All the CPs are characterized by single-crystal X-ray diffraction analyses, powder X-ray diffraction (PXRD), elemental analyses, IR spectroscopy, and TGA analyses. Moreover, the weak ferromagnetic properties of 2 and 3 and antiferromagnetic properties of 1 and 4 have also been investigated. [ABSTRACT FROM AUTHOR]

A tetrakis(bisurea)-decorated tetraphenylethene (TPE) ligand (L2) was designed, which, upon coordination with phosphate ions, displays fluorescence "turn-on" over a wide concentration range, from dilute to concentrated solutions and to the solid state. The fluorescence enhancement can be attributed to the restriction of the intramolecular rotation of TPE by anion coordination. The crystal structure of the A4L2 (A=anion) complex of L² with monohydrogen phosphate provides direct evidence for the coordination mode of the anion. This "anion-coordination-induced emission" (ACIE) is another approach for fluorescence turn-on in addition to aggregation-induced emission (AIE). [ABSTRACT FROM AUTHOR]

Through tuning the nature of the secondary ligands, the ligand-to-metal molar ratio and the metal ions, four coordination polymers, namely {[Ni2(bcp)2(4,4'-bipy)2(H2O)4]·3.5H2O}2 (1), {[Co2(bcp)2(bpt)2].2.29H2O.bpt}n (2), [Co2(bcp)2(bib)]n (3) and {[Co(bcp)(2,2'-bipy)(H2O)]·H2O}n (4), have been synthesized and characterized. The structural feature of 1 shows a 3D three-fold parallel interpenetrating framework with CdSO4 topology. 2 exhibits a 2D→3D interpenetrating motif with pseudorotaxane. Compound 3 shows two identical 2D layers with 22'48'65 topology that are interpenetrated in a parallel fashion, resulting in a twofold interpenetrating motif containing polyrotaxane and polycatenane character. However, a 1D zipper-like double-stranded chain is observed in polymer 4. This work evidently indicates that the effect of the secondary ligands and geometric preferences of the metal centers are critical in the construction of the resulting networks. In addition, the magnetic properties of compounds 2 and 3 were also discussed. [ABSTRACT FROM AUTHOR]

Two new three-dimensional (3D) porous structures based on the mixed flexible and rigid organic ligands, [Cd1.5(bmip)(tpa)1.5(DMF)1.5]n (1) and [Co1.5(bmip)0.5(bpdc)1.5(DMF)2]n (2) (bmip = 1,3-bis(2-methylimidazolyl)propane, H2tpa = terephthalic acid, H2bpdc = biphenyl-4,4'-dicarboxylic acid, DMF = N,N-dimethylformamide) have been prepared under solvothermal conditions. Complex 1 contains a trinuclear Cd unit, in which the trinuclear Cd cluster acts as an eight-connected node with two pairs of flexible bmip and six rigid tpa ligands. Complex 2 exhibits a two-fold interpenetrated porous network based on a trinuclear Co cluster as eight-connected vertices with two flexible bmip and six rigid tpa ligands. Both 1 and 2 show selective gas adsorption of CO2 over N2 and H2. Furthermore, complex 1 displays an uncommon CO2 adsorption isotherm and hysteretic desorption behaviors at 195 K. [ABSTRACT FROM AUTHOR]

By reacting an asymmetry semi-rigid Y-shaped/L-shaped linker H3cpta (H3cpta = 3-(4'-carboxyphenoxy)- phthalic acid) and Co(CH3COO)3'6H2O under different N-donor ligands in different solvents, three new Co-based coordination polymers, [Co3(cpta)2(bpe)3(H2O)4] (1) [Co(μ2-H2O)(μ3-OH)(Hcpta)(bpe)(H2O)' 3(DMF)3(H2O)] (2) and [Co3(cpta)2(bpa)4] (3) have been obtained. They exhibit trinodal topological nets/ layer, based on Co2+ ions and Y-shaped/L-shaped carboxylate linkers. 1 and 3 present 3D frameworks with the point symbol {4·102}2{105·12}{4·85}2 for 1 and {4·82}3{85·9}{4·67·92}3 for 3. While, 2 exhibits a 2D layer with the point symbol {4·6·8}{4·62·83}{62·8}. The magnetic studies indicate that all of the three complexes show antiferromagnetic exchanges transmitted through μ3-carboxylate/μ4-carboxylate bridges, μ2- H2O molecules and μ3-OH ions between Co2+ ions, respectively. And the result of this research shows that the solvent and the secondary ligands could co-regulate coordination polymer with interesting properties, providing a constructive guidance when synthesizing versatile topologies with the same organic spacer but a different architecture. [ABSTRACT FROM AUTHOR]

Three new complexes, {[Mn(dtb)(bpe)·2H2O]·H2O}n(1), {[Mn(dtb)(bpa)·2H2O]·H2O}n(2), and {[Mn(dtb)(phen)]}n(3) [H2dtb = 5,5′-dithiobis(2-nitrobenzoic acid), bpe = 1,2-bis(4-pyridyl)ethene, bpa = 1,2-bi(4-pyridyl)ethane, phen = 1,10-phenanthroline], have been synthesized under hydrothermal conditions with Mn(OAc)2·4H2O, dtb, and differentN-donor ligands. X-ray structure analyses of1and2reveal analogous structures with 1D helical chains and 2D 44chiral layers. The structure of3shows a 1D chain which is outwardly decorated with phen ligands. These neutral polymeric complexes exhibit structural diversity due to the different coordination modes of the flexible dtb ligand and the N-donor ligands. The thermogravimetric analyses and X-ray powder diffractions of1–3are also presented. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis, structure and magnetic property of a new coordination network {[Co2(bcp)2(bpt)2]·2H2O}n (1) (H2bcp=1,3-bis(4-carboxy-phenoxy)propane and bpt=2,5-bis(4-pyridyl)-1,3,4-thiadiazole), is reported. Complex 1 shows a 3D 48.66.8 topology with unusual self-penetration, in which represents a new example of 6-connected networks. In addition, the magnetic property of 1 has also been investigated. [Copyright &y& Elsevier]

Self-assembly of rigid dicarboxylate and flexible N-donor co-ligands in the presence of divalent metal ion affords a new polymer of [Cu(bpea)(bib)] ( 1) (bpea = biphenyle-thene-4,4′-dicarboxylate and bib = 1,4-bis(2-methyl-imidazol-1-yl)butane). The structure of 1 exhibits an unusual 2D → 3D motif with sql topology. Graphical Abstract: An interesting 3D polycatenane metal-organic framework was obtained from the assembly of mixed rigid and flexible in the presence of transition metal. The structure reported herein demonstrates that backbone of organic acid play the central role of a structure-directing unit[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new metal-organic framework, {[Co1.5(μ2-OH)(L)(bipy)0.5] ·0.5DMF}n (1) (H2L = (4,4'-(hexafluoroisopropylidene)bis(benzoic acid) and bipy = 4,4'-bipyridine), has been prepared under solvothermal conditions using flexible dicarboxylate and rigid N-donor co-ligands in the presence of Co(II) ion as the building blocks. The x-ray single-crystal diffraction analysis indicates that 1 possesses a three-dimensional (3D) layer-pillar structure with one-dimensional (1D) metal-carboxylate chain. The Co(II) ions are bridged by L2- to generate a two-dimensional (2D) sheet, which is further pillared by bipy into a 3D framework with {44.62}{45.65}2 topology. In addition, the variable-temperature magnetic susceptibility measurement indicates there exists an anti-ferromagnetic behavior between in the Co(II) ions of 1. [ABSTRACT FROM AUTHOR]

Along with our recent investigation on the flexible ligand of H2ADA (1,3-adamantanediacetic acid), a series of ZnIIand CdIImetal–organic frameworks, namely, [Zn3(ADA)3(H2O)2]n·5nH2O (1), [Zn(ADA)(4,4′-bipy)0.5]n(2), [Zn2(ADA)2(bpa)]n(3), [Zn2(ADA)2(bpa)]n(4), [Zn2(ADA)2(bpp)]n(5), [Cd(HADA)2((4,4′-bipy)]n(6), [Cd3(ADA)3(bpa)2(CH3OH)(H2O)]n(7), and [Cd2(ADA)2(bpp)2]n·7nH2O (8) have been synthesized and structurally characterized (where 4,4′-bipy = 4,4′-dipyridine, bpa = 1,2-bis(4-pyridyl)ethane and bpp = 1,3-bis(4-pyridyl)propane). Due to various coordination modes and conformations of the flexible dicarboxylate ligand and the different pyridyl-containing coligands, these complexes exhibit structural and dimensional diversity. Complex 1exhibits a three-dimensional (3D) framework containing one-dimensional (1D) ZnII–O–C–O–ZnIIclusters. Complex 2exhibits a 2D structure constructed by 1D double chains based on [Zn2ADA2] units and a 4,4′-bipy pillar. Complexes 3and 4possess isomorphic 2D layer structures, resulting from the different coordination modes of carboxylate group of ADA ligands. Complex 5features a 2D 44layer in which ADA ligands and ZnIIatoms construct a 1D looped chain and the chains are further connected by bpp ligands. Complex 6is composed of 1D zig-zag chains that are entangled through hydrogen-bonding interactions to generate a 2D network. Complex 7is a rare (3,5)-connected network. Complex 8possesses a 3D microporous framework with lots of water molecules encapsulated in the channels. The structural diversity of the complexes perhaps mainly results from using diverse secondary ligands and different metal centre ions, and means the assistant ligand and metal centre play important roles in the design and synthesis of target metal–organic frameworks. This finding revealed that ADA could be used as an effective bridging ligand to construct MOFs and change coordination modes and conformational geometries in these complexes. The thermogravimetric analyses, X-ray powder diffraction and solid-state luminescent properties of the complexes have also been investigated. [ABSTRACT FROM AUTHOR]

Six new coordination polymers, namely {[Zn(btec)0.5(btmb)]·2H2O}n(1), {[Co(btec)0.5(btmb)(H2O)]·3H2O}n(2), {[Cu(btec)0.5(btmb)]·H2O}n(3), {[Cu4(btc)4(btmb)4]·H2O}n(4), {[Co3(bta)2(btmb)2]·2H2O}n(5), [Co(Hbta)(btmb)]n(6) (H4btec = 1,2,4,5-benzenetetracarboxylate, H3btc = 1,3,5-benzenetricarboxylate, H3bta = 1,2,4-benzenetricarboxylate and btmb = 4,4′-bis(1,2,4-triazol-1-ylmethyl)biphenyl), have been successfully synthesized under hydrothermal conditions. All these complexes were structurally determined by single-crystal X-ray diffraction, elemental analysis, IR, TGA and XRD. Crystal structural analysis reveals that 1is the first example of an unusual 3D framework with (86) topology containing a 2D molecular fabric structure. Complex 2exhibits a 3D NbO network with (64·82) topology. In 3, Cu(ii) ions are coordinated by anti-conformational btmb ligands to form left- and right-handed double helices, which are further bridged by the 4-connected btec4−anions to give a 3D porous network. Complex 4presents a rare 3D gra network structure with (63)(69·8) topology. 5and 6were obtained through controllable pH values of solution, 5features a scarce binodal (3,8)-connected tfz-d framework with the trinuclear Co(ii) clusters acting as nodes, whereas 6has an extended 2D 44grid-like layer and the adjacent 2D layers are interconnected by strong hydrogen bonding interactions into a 3D supramolecular framework. The structural diversities indicate that distinct organic acid ligands, the nature of metal ions and the pH value play crucial roles in modulating the formation of the resulting coordination complexes and the connectivity of the ultimate topological nets. Moreover, magnetic susceptibility measurement of 5indicates the presence of weak ferromagnetic interactions between the Co(ii) ions bridged by carboxylate groups. [ABSTRACT FROM AUTHOR]

The solvothermal reactions of CuCN with two structure-related flexible 4-pyridyl dithioether ligands, bis(4-pyridylthio)methane (L1) and 1,2-bis(4-pyridylthio)ethane (L2), generated two novel three-dimensional (3D) coordination polymers: [(CuCN)5(L1)2]n(1) and [(CuCN)3(L2)]n(2), respectively. Their structures were determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectra, and thermogravimetric analyses. Complex 1is constructed by the interconnection of CuCN layers with L1 pillars to form an interesting self-penetrating 123topological network with characteristic of four distinct helical chains. In 2, each L2 acting as a quadridentate μ3-bridge connects Cu atoms from three uncommon meso-helical CuCN chains, to give 3D framework containing 1D tubes constructed by two types of helical chains with opposite chirality. 2exhibits a 3-fold interpenetrating network with a rare (62·10)2(6·102) topology. In addition, the solid state samples of 1and 2exhibited different luminescent properties at room temperature. [ABSTRACT FROM AUTHOR]

A series of new metal–organic coordination complexes, [Zn(cpds)(H2O)2]n(1), {[Zn(cpds)(4,4′-bipy)]·6H2O}n(2), {[Zn(cpds)(bpe)]2·0.5(bpe)·4H2O}n(3), [Cu(cpds)(2,2′-bipy)(CH3OH)]2·2H2O (4), {[Cu(cpds)(4,4′-bipy)(H2O)2]·2.24H2O}n(5), {[Cu(6-sinic)(4,4′-bipy)0.5]·CH3OH·H2O}n(6), [Cd2(6-mna)2(phen)]n(7), and {[Cd(cpds)(bpe)]·2.2H2O}n(8) were prepared by self-assembly of disulfide derivative of the nicotinate, 6,6′-dithiodinicotinic acid (H2cpds) with transition metal ions in the absence of different N-donor ligands (4,4′-bipy = 4,4′-bipyridine, 2,2′-bipy= 2,2′-bipyridine, phen = 1,10-phenanthroline, bpe = 1,2-bis(4-pyridyl)ethene, 6-sinic = 6-sulfinto-nicotinate, 6-mna = 6-mercaptonicotinic acid). X-Ray structure analyses of 1–8reveal their structure ranging from the discrete unit (0D) (4), one-dimensional (1D) (1, 5), two-dimensional (2D) (7), non-interpenetrating 3D porous coordination polymers (6, 8), 2-fold interpenetrated structure (2) to a 5-fold interpenetrating framework (3), which mainly due to the differences in the bridging modes of cpds2−and the effect of the secondary ligands. Interestingly, in the complexes 6and 7, the starting H2cpds reagent is converted into new ligands (6-sinic in 6and 6-mna in 7) under solvothermal condition viain situcleavage of S–S bond. In addition, thermogravimetric analyses, X-ray powder diffractions and the fluorescent properties of complexes 1, 2, 3, 7, 8have been investigated. [ABSTRACT FROM AUTHOR]

A series of new metal–organic coordination complexes, [Zn(cpds)(H2O)2]n(1), {[Zn(cpds)(4,4′-bipy)]·6H2O}n(2), {[Zn(cpds)(bpe)]2·0.5(bpe)·4H2O}n(3), [Cu(cpds)(2,2′-bipy)(CH3OH)]2·2H2O (4), {[Cu(cpds)(4,4′-bipy)(H2O)2]·2.24H2O}n(5), {[Cu(6-sinic)(4,4′-bipy)0.5]·CH3OH·H2O}n(6), [Cd2(6-mna)2(phen)]n(7), and {[Cd(cpds)(bpe)]·2.2H2O}n(8) were prepared by self-assembly of disulfide derivative of the nicotinate, 6,6′-dithiodinicotinic acid (H2cpds) with transition metal ions in the absence of different N-donor ligands (4,4′-bipy = 4,4′-bipyridine, 2,2′-bipy= 2,2′-bipyridine, phen = 1,10-phenanthroline, bpe = 1,2-bis(4-pyridyl)ethene, 6-sinic = 6-sulfinto-nicotinate, 6-mna = 6-mercaptonicotinic acid). X-Ray structure analyses of 1–8reveal their structure ranging from the discrete unit (0D) (4), one-dimensional (1D) (1, 5), two-dimensional (2D) (7), non-interpenetrating 3D porous coordination polymers (6, 8), 2-fold interpenetrated structure (2) to a 5-fold interpenetrating framework (3), which mainly due to the differences in the bridging modes of cpds2−and the effect of the secondary ligands. Interestingly, in the complexes 6and 7, the starting H2cpds reagent is converted into new ligands (6-sinic in 6and 6-mna in 7) under solvothermal condition viain situcleavage of S–S bond. In addition, thermogravimetric analyses, X-ray powder diffractions and the fluorescent properties of complexes 1, 2, 3, 7, 8have been investigated. [ABSTRACT FROM AUTHOR]

Abstract: Reaction of disulfide-containing ligand 6,6′-dithiodinicotinic acid (H2cpds) with lanthanide metal salts led to three compounds {[Ln2(cpds)3(H2O)5]·7H2O} n (Ln=Gd, 1; Tb, 2; Er, 3) under hydrothermal conditions. The single-crystal X-ray diffraction analysis revealed that complexes 1–3 are isostructural. Two eight-coordinated metal centers are connected with carboxylate groups of H2cpds to give a binuclear [Ln2(CO2)4] unit. H2cpds discloses two independent binding modes resulting in the two types of 1-D chains by the connection of [Ln2(CO2)4] unit. Finally, the 1-D chains are linked by H2cpds to construct a 3-D network with an uncommon twofold interpenetrating 4-connected CdSO4 structure type (65,8 topology). It is worth noting that polyrotaxane-like motif is also exhibited in the 3-D network. The Tb(III) compound exhibits strong green photoluminescence in the visible region. Furthermore, the magnetic property of the Gd(III) compound has been investigated in the temperature range of 2–300K. The thermal behaviors and XPRD patterns of three compounds have also been discussed. [ABSTRACT FROM AUTHOR]

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-1presents 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. [ABSTRACT FROM AUTHOR]

This article represents a systematical investigation on the structures of silver(i) dicarboxylate incorporating secondary ligands, revealing that the secondary interactions could play an important role in interlinking low-dimensional entities to high-dimensional supramolecular frameworks. A new 2D silver(i) crystalline dicarboxylate, {[Ag6(ADC)3(H2O)1.5]2·5.18H2O}n(1) (H2ADC = 1,3-adamantanedicarboxylic acid), has been obtained by slow diffusion of corresponding precursors. To investigate the influence of the properties of pyridylic neutral ligands on the complex structures based on compound 1, five kinds of neutral ligands (bipy = 4,4′-bipyridine; bpa = 1,2-bis(4-pyridyl)ethane; bpe = 1,2-bis(4-pyridyl)ethene; bpp = 1,3-bis(4-pyridyl)propane; bpdap = N,N′-bis(3-pyridyl)-2,6-diaminopyridine) were selected, and a series of new silver(i) dicarboxylate have been synthesized: {[Ag(bpa)(HADC)]}n(2), {[Ag(bpp)(HADC)]·CH3OH}n(3), {[Ag4(bpe)3(ADC)2]·2H2O}n(4), {[Ag(bipy)(HADC)]·H2O}n(5), {[Ag2(bipy)2(ADC)]·6H2O}n(6), and [Ag8(bpdap)4(ADC)4]·2C2H5OH·6H2O (7). Single-crystal X-ray structural analysis shows that complexes 1and 4are formed by hexanuclear and tetranuclear Ag(i) clusters with weak Ag–Ag interactions. Complexes 2and 3are dinuclear structures, 5and 6exhibit an infinite 1D chain structure, whereas 7is a discrete octanuclear Ag(i) unit. The structures of 1–7span from dinuclear, tetranuclear, hexanuclear, to octanuclear Ag(i) complexes, which indicates that secondary ligands do play important roles in the formation of such coordination architectures. Thermal stability, X-ray powder diffraction and luminescent properties of the compounds are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Via hydrothermal synthesis, the self-assembly of d10 metal, 2,4′-dipyridylamine (L) and 1,3-adamantanediacetic acid (H2ADA) generated two unprecedented coordination polymers [Zn(ADA)(L)] n (1) and [Cd(ADA)(L)2] n (2). Complex 1 possesses a novel 1D looped-chain topology structure decorated with arms. Complex 2 shows an extended threaded framework involving 2D coordination layers of square (44) topology with dangling ligands, which gives the novel (2D→3D) polythreaded array. To the best of our knowledge, complex 2 is the first example with four dangling arms coordinated in the axial sites of dinuclear nodes. In addition, both of the complexes show strong photoluminescence at room temperature, and may be good candidates for potential luminescence materials. [Copyright &y& Elsevier]

Abstract: Six new coordination polymers based on V-shaped linkage 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and transition metal ions, [Co(bpt)(pm)0.5(H2O)] n ·3nH2O (1), [Cu2(bpt)(pm)(H2O)4] n (2), [Co(bpt)(pydc)] n ·2nCHCl3 · nH2O (3), [Cu2(bpt)(pydc)2(H2O)2] n (4), [Cu2(bpt)(pydco)2(H2O)2] n · nH2O (5) and [Cd(bpt)(pydco)] n (6) (H4pm=pyromellitic acid, H2pydc=pyridine-2,6-dicarboxylic acid, H2pydco=pyridine-2,6-dicarboxylic acid N-oxide), have been synthesized under the intervention of various polycarboxylate ligands. Complex 1 exhibits a 3-D 4-connected structure with 1-D nanosized open channels encapsulated lots of water molecules. Complex 2 represents a 2-D grid containing two types of rectangular windows. When pydc and pydco instead of pm, complexes 3 and 6 were obtained with highly undulated 2-D layers. The interlayers of 3 are filled with two kinds of solvent molecules, whereas 6 is a double-layered framework without free molecules. Complexes 4 and 5 consist of two distinct 1-D infinite chains held together to form different 2-D supramolecular networks. Importantly, bpt spacer shows changeful conformational geometries and generates complicated crystalline architectures with the introduction of polycarboxylate ligands. Additionally, thermal stability of complexes 1, 3 and 5, fluorescent properties of 6 and X-ray powder diffraction of 1 have also been investigated. [Copyright &y& Elsevier]

Five new Mn(II) metal–organic coordination polymers, [Mn(tbip)(bipy)]n(1), {[Mn(tbip)(dpe)]·1.5H2O}n(2), [Mn(tbip)(bpa)]n(3), [Mn(mip)(bpa)]n(4) and {[Mn3(mip)2(Hmip)2(bpp)2(H2O)2]·2H2O}n(5), were prepared through hydrothermal reactions of Mn(II) acetate with H2tbip (H2tbip = 5-tert-butyl isophthalic acid) or H2mip (H2mip = 5-methylisophthalic acid) in the presence of different dipyridyl co-ligands (bipy = 4,4′-bipyridine, dpe = 1,2-bi(4-pyridyl)ethene, bpa = 1,2-bi(4-pyridyl)ethane and bpp = 1,3-di(4-pyridyl)propane). All these compounds were characterized by elemental analysis, IR spectroscopy and X-ray single-crystal diffraction. The structures of 1and 2are constructed of [Mn2(tbip)2]nlayers, which consist of alternate left- and right-handed helical chains, and further pillared by bipy or dpe ligands into a 3D porous framework. Interestingly, there are two different sizes of pores in 1and 2. From the topology point of view, both complexes 1and 2exhibit the rare rob network based on the dimeric [Mn(COO)]2subunits as the 6-connected nodes. The ribbon-like chains having 8- and 16-membered rings in 3and 4result from dimeric Mn(II) units bridged by H2tbip or H2mip ligands, which are connected by the flexible dpa into 2D open layers. Complex 5contains rare isophthalato-bridged trimanganese clusters as building units, which are further linked by mip anions to form a one-dimensional ladder-like chain with less common unidentate coordinated bpp decorated as pendants. The thermal stabilities and X-ray powder diffraction studies indicate that the microporous framework of 2can keep stable even after the loss of guest water molecules. In addition, dominant antiferromagnetic coupling was observed in compounds 1–3and 5. [ABSTRACT FROM AUTHOR]