Syntheses, crystal structures and properties of three novel coordination polymers with tripodal imidazole-containing ligands and benzenetetracarboxylate

Three novel coordination polymers, [Ni₂(tib)₂(btec)]·2H₂O (1), [Co₂(tib)₂(btec)]·2H₂O (2) and [Zn₄(tib)₂(btec)Cl₄]·2H₂O (3), have been synthesized by using mixed ligands of 1,3,5-tris(1-imidazolyl)benzene (tib) and 1,2,4,5-benzenetetracarboxylic acid (H4btec) under hydrothermal conditions. Complexes 1 and 2 have the same structure and are rare three-dimensional (3D) self-penetrating (3,4,5)-connected nets, while complex 3 is an unprecedented (3,4)-connected 3D net. The different structures of 1 (2) and 3 are ascribed to the distinct coordination geometry of the metal centers. The thermal stability and photoluminescence property of the complexes were investigated.     

Two d 10-metal coordination polymers constructed from flexible ligands: Syntheses, crystal structures, and luminescent properties

Two new complexes, Zn(Glut)(Bix) · 2H₂O (I) and Cd(Pda)(Bimb) (II) (H₂Glut = glutaric acid, H₂Pda = 1,3-phenylenediacetic acid, Bix = 1,4-bis(imidazol-1-ylmethyl)benzene and Bimb = 1,4-di(1H-imidazol-1-yl)butane) were obtained under hydrothermal conditions by employing mixed ligands with metal salts and characterized by elemental analysis, IR, TGA, and Single crystal X-ray diffraction. Complex I presents a two-dimensional 2-fold interpenetrating layer structure. Whereas complex II is a two-dimensional layer network and exhibits a typical (4,4) topological net. The infrared spectra, thermogravimetric and luminescent properties were also investigated in detail for two complexes.     

Syntheses,crystal structures and photoluminescence of three coordination polymers with 2,3-pyrazinedicarboxylic acid and N-donor ligands

The reactions between Cd(OAc)₂/Cu(NO₃)₂ and mixed ligands (2,3-pyrazinedicarboxylic acid (pzdc) and N-donor ligands) under different reaction conditions give the three title complexes 1, 2 and 3. There is a (4,8) net 2D network structure and a rectangular grid network structure in the cadmium complexes [Cd(pzdc)(phen)] · H₂O (1) and Cd₂(pzdc)₂(4,4′-bpy)(H₂O)₂ (2), respectively. The complex [Cu₄(pzdc)₄(phen)₂(H₂O)₄] · 10H₂O (3) has a 1D zigzag chain structure. The influences of coordination modes of the pzdc ligand and N-donor ligands on the superstructural diversity have been discussed. Complexes 1 and 2 exhibit strong fluorescent emission bands in the solid state at room temperature. The EPR spectrum of 3 is typical for a square-pyramidal geometry of copper (II) ions.     

Syntheses,structures and fluorescent properties of three copper cyanide coordination polymers based on N-heterocyclic ligands

Hydrothermal reactions of CuCN, K₃[Fe(CN)₆] with 2,2′-bipyridine, 1,10-phenanthroline or 2,6-bis(1,2,4-triazolyl)pyridine (btp) afford three coordination polymers, [Cu₇(CN)₇(bipy)₂] _n (1), [Cu₂(CN)₂(phen)] _n (2) and [Cu₃(CN)₃(btp)] _n (3). Complex 1 displays 1D polymeric ribbons which are assembled through Cu ··· Cu and π–π stacking interactions into a 3D framework. Complex 2 shows a 1D zigzag chain structure in which phen is a side ligand. In 3, the copper cyanide 2D polymeric networks are connected by tridentate btp to form a 3D metal-organic framework. These coordination polymers exhibit strong fluorescent emissions in the solid state.     

Different crystal structures and luminescent properties of zinc and cadmium coordination polymers constructed from two flexible thioether ligands with different alkyl chains

Treatments of nitrogen-containing heterocyclic dithioether ligands, 1,2-bis(4-(pyridin-3-yl) pyrimidin-2-ylthio) ethane (L¹) and 1,3-bis (4-(pyridin-3-yl) pyrimidin-2-ylthio) propane (L²), with zinc or cadmium salts have resulted in the interesting frameworks with structural motifs from a mononuclear macrocycle or a dinuclear macrocycle to an one-dimensional structure. A small difference of the alkyl length between L¹ and L² led to conspicuous changes of the fluorescent properties of both ligands and their complexes. Mainly due to the size of metal atoms, structures of [ZnL²I₂] (1) and [CdL²I₂] (2) are varied from a mononuclear macrocycle to a 1D framework, while {[ZnL²(H₂O)₄](ClO₄)₂}₂ (3) and {[CdL²(H₂O)₄](ClO₄)₂}₂ (4) are dinuclear macrocycles in which perchlorate anions may play an important template role. As for complexes 5–8 ([ZnL¹I₂]_n (5), [CdL¹I₂]_n (6), {{[ZnL¹₂(H₂O)₄](ClO₄)₂}_0.5 · L¹_0.5 · CH₃OH} (7), {{[Cd_0.5L¹(H₂O)₂](ClO₄)}₂ · CH₃OH · L¹} (8)), the self-assemble processes were mainly directed by the organic ligand in the reactions of L¹ with metal salts. Complexes 1–4 exhibit blue fluorescence emissions, among which 1 and 2 may be suitable as candidates for blue fluorescent materials.     

Syntheses,crystal structures,and magnetic and luminescent properties of a series of lanthanide coordination polymers with chelidamic acid ligand

A series of lanthanide(III) complexes with chelidamic acid ligand, [Ln(C₇H₂NO₅)·3H₂O]_n·nH₂O (Ln = La (1), Y (2), Sm (3), and Nd (4)), [Gd₂(C₇H₂NO₅)₃·4H₂O]_n·2nH₂O (5) and [Ce(C₇H₂NO₅)·1.5H₂O]_n (6), have been synthesized by hydrothermal method and structurally characterized by single-crystal X-ray diffraction. Complexes 1–4 are isostructural and possess 2D framework. Complex 5 contains two different Gd(III) ions linked through carboxylate group to form a 2D framework. Complex 6 exhibits a (4⁴) topology 2D network. The variable-temperature magnetic properties of 3 and 5 have been investigated. Furthermore, the photoluminescent properties of 1, 2, 3, and 5 at room temperature were also studied.     

New heterometallic coordination polymers based on zinc(II) complexes with Schiff-base ligands and dicyanometallates: synthesis,crystal structures,and luminescent properties

Four new d¹⁰ heterometallic coordination polymers have been obtained using three Schiff-base ligands, zinc(II) nitrate, and dicyanometallates: ₁^∞[{Zn₃(Salen)₂}{μ-Au(CN)₂}₂] (1); ₁^∞[Zn(Saldmen){μ-Ag(CN)₂}]·2H₂O (2); ₁^∞[Zn(Salampy){μ-Ag(CN)₂}] (3); ₁^∞[Zn(Salampy){μ-Au(CN)₂}] (4). The Schiff bases are obtained from condensation of salicylaldehyde with ethylenediamine (H₂Salen); N,N-dimethyl-ethylenediamine (HSaldmen) and, respectively, 2-aminomethyl-pyridine (HSalampy). The dicyanometallates are K[Ag(CN)₂] and K[Au(CN)₂]. The compounds were characterized by X-ray single-crystal diffraction, infrared spectroscopy, UV–vis spectroscopy, and elemental analysis. In compound 1, the homotrimetallic units, {Zn₃(salen)₂}²⁺, are connected by two [Au(CN)₂]^? bridges, forming a 1-D double chain. In compounds 2–4, the crystal structures show polymeric zigzag chains generated by the mononuclear zinc(II) nodes and [M(CN)₂]^? spacers. The luminescence properties of the new heterometallic polymers have also been investigated.     

Syntheses,crystal structures,and magnetic properties of 1-D coordination polymers

Three coordination polymers of Robson-type macrocycles, {[Cu₄L¹(4,4′-bipy)₂]·4ClO₄·H₂O}_∞ (1), {[Cu₄L²(4,4′-bipy)₄]·2CH₃CN·4ClO₄·2H₂O}_∞ (2), and {[Zn₂L²(4,4′-bipy)₂]·(ClO₄)₂}_∞ (3) (where H₂L¹ and H₂L² are the [2?+?2] condensation products of 1,3-diaminopropane with 2,6-diformyl-4-methylphenol and 2,6-diformyl-4-fluorophenol, respectively), have been synthesized and characterized. Magnetic susceptibility was measured for 1 and 2 from 2 to 300?K. The optimized magnetic data were J?=?–368.5?cm^?1, J′?=?40.5?cm^?1 with R?=?1.69?×?10^?6 for 1 and J?=?–291.22?cm^?1, J′?=?83.74?cm^?1, ρ = 0.00168 with R?=?1.8?×?10^?11 for 2, respectively. The data reveal strong antiferromagnetic interactions between two Cu(II) ions in the macrocyclic unit and ferromagnetic interaction between the Cu(II) ions in two adjacent macrocyclic units for 1 and 2.     

Syntheses,crystal structures and luminescent properties of two new Zn(II) coordination polymers based on a dicarboxylate and different imidazole-containing ligands

To investigate the effect of different imidazole-containing ligands on the structure of coordination polymers, two new Zn(II) coordination polymers based on 1,4-cyclohexanedicarboxylic acid (H₂cda) and two different imidazole-containing ligands, [Zn(cda)(bib)_0.5]_n (1) and [Zn(cda)(bmib)_0.5]_n (2) (bib = 1,4-bis(imidazol-1-yl)benzene and bmib = 1,4-bis(2-methylimidazol-3-ium-yl)benzene), have been synthesized and characterized by single-crystal X-ray diffraction. Complex 1 shows a 3-D structure with point symbol (4.8².10³).(4.8²). Complex 2 displays a 2-D layer structure with an –AB– stacking sequence.     

Assembly,crystal structures,and luminescent properties of three new thiocyanate-bridging mercury(II) coordination polymers

Two ligands, 2-{5,5-dimethyl-3-[2-(pyridin-3-yl)-ethenyl]cyclohex-2-enylidene}propanedinitrile (L1) and 2-{5,5-dimethyl-3-[2-(pyridin-2-yl)-ethenyl]cyclohex-2-enylidene}propanedinitrile (L2), were synthesized. By reaction of mercury thiocyanate with L1 and L2, respectively, coordination polymers [Hg(L1)(μ_1,3-SCN)₂]_n (1), [Hg(L1)₂(μ_1,3-SCN)₂]_n (2), and [Hg(L2)(μ_1,3-SCN)(SCN)]_n (3) with different structures and topologies were obtained. In 1, the thiocyanate shows μ_1,3-SCN bridging coordination, and adjacent Hg(II) ions are bridged by two μ_1,3-SCN ions to form an infinite chain with the remaining position of five-coordinate Hg(II) occupied by L1. In 2, the thiocyanate has the same coordination as 1. However, Hg(II) has octahedral coordination with two L1 involved in coordination. An unusual feature of 3 is the presence of two types of thiocyanates, one has a S-terminal ligand and the other has a μ_1,3-SCN bridge. The mercury(II) in 3 is four-coordinated by L2 and three thiocyanates. Luminescent properties and thermal stabilities of 1–3 were studied.     

Syntheses, crystal structures, and luminescent properties of novel layered lanthanide sulfonate-phosphonates

Hydrothermal reactions of lanthanide metal salts with MeN(CH(2)CO(2)H)(CH(2)PO(3)H(2)) (H(3)L) and 5-sulfoisophthalic acid monosodium salt (NaH(2)BTS) lead to four isomorphous lanthanide carboxylate-phosphonate-sulfonate hybrids, namely, Ln(H(2)L)(HBTS)(H(2)O)(2).H(2)O (Ln = La (1), Pr (2), Nd (3), Gd (4)). Their structures have been established by X-ray single-crystal diffraction. The interconnection of the lanthanide(III) ions by carboxylate-phosphonate ligands results in a 1D double chain; these double chains are further bridged by bidentate bridging carboxylate-sulfonate ligands to form a <011> layer. The luminescent properties of compounds 3 and 4 have also been studied.     

Novel coordination polymers with ferrocene-containing dicarboxylate ligand: Syntheses, crystal structures and properties

A new ferrocene-containing dicarboxylate ligand, L = 5-ferrocene-1,3-benzenedicarboxylic acid, has been prepared. Self-assembly of L, M(II) salts (M = Co and Zn) and chelating ligands dpa or phen (dpa = 2,2′-dipyridylamine and phen = 1,10-phen) gave rise to four new coordination polymers {[Co(L)(dpa)] · 2MeOH}_n (1), {[Zn(L)(dpa)] · 2MeOH}_n (2), {[Co(L)(phen)(H₂O)] · MeOH} (3), [Zn(L)(phen)(H₂O)] · MeOH (4). The isostructural complexes 1 and 2 possess 1D helical chain structures with 2₁ screw axes along the b-direction, and the right- and left-handed helical chains are alternate arrayed into 2D layer structures through hydrogen-bonding interactions; while isostructural complexes 3 and 4 are 1D linear chain structures with phen and ferrocene groups of L as pendants hanging on the different sides of the main chain. A structural comparison of complexes 1–4 demonstrated that the characteristics of subsidiary ligands and slight difference in coordination models of L play very important role in the construction of the complexes. In addition, the redox properties of complexes 1–4, as well as the magnetic properties of complexes 1 and 3 are also investigated.     

Syntheses,crystal structures,and photophysical properties of two 2-D coordination polymers

Two coordination polymers, [Mn(dipt)(m-BDC)₃] _n (1) and [Pb(mip)(1,4-NDC)] _n (2) [dipt?=?2-(2,4-dichlorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, mip?=?2-(3-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, m-BDC?=?isophthalic acid, 1,4-NDC?=?naphthalene-1,4-dicarboxylic acid], have been synthesized by hydrothermal reactions and characterized by elemental analysis, thermogravimetric analysis, infrared spectrum, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction reveals that 1 and 2 have 1-D chain architecture. Complex 1 has a 2-D-layered structure constructed from C–H···O hydrogen bonds. Complex 2 has a 2-D-layered structure constructed from N–H···O hydrogen bonds and π–π interactions. TG analyses suggest 1 and 2 have excellent thermal stabilities from hydrogen bonds and π–π interactions. Mn(II) in 1 has trigonal bipyramidal geometry surrounded by three carboxylate oxygen atoms from three monodentate bridging m-BDC and two nitrogen atoms from one dipt. Pb(II) has [:PbN2O4] pentagonal bipyramidal geometry in 2. The luminescent properties for dipt, mip, 1, and 2 are also presented.     

Three one-dimensional chains with bulky backbone carboxylate ligands: Syntheses,crystal structures,and luminescent properties

To explore the influence of bulky backbone on complexes, three Co(II) and Zn(II) complexes with phenanthrene-9-carboxylate (L¹), 9H-fluorene-9-carboxylate (L²) or biphenyl-4-carboxylate (L³) together with incorporating auxiliary bridging ligad 4,4′-bipyridine (4Bipy), were synthesized and characterized: [Co(L¹)₂(4Bipy)(H₂O)₂]_∞ (I), [Zn(L²)₂(4Bipy)_0.5(4Bipy)_0.5]_∞ (II), and [Zn₃(L³)₄(4Bipy)_0.5(4Bipy)_0.5(4Bipy)_0.5(OH)₂]_∞ (III). X-ray single-crystal diffraction analyses show that complexes I–III both assume one-dimensional (1D) structures by incorporating the bridging 4Bipy (CIF file CCDC nos. 942729 (I), 942727 (II), and 942733 III). In I, mononuclear six-coordinated Co²⁺ ions are linked into a 1D linear chain by 4Bipy. While in II, mononuclear four-coordinated Zn²⁺ ions are linked into a 1D zigzag chain by 4Bipy. But in III, because of the existence of OH^?, hexanuclear Zn(II) can be regarded as a node, then bridge adjacent hexanuclear Zn(II) nodes by almost parallelled three 4Bipy ligands into a 1D linear chain. Finally the 1D chains of I–III are further assembled into an overall three-dimensional (3D) framework via intermolecular H-bonding, π…π stacking, and/or C-H…π supramolecular interactions, respectively. The results indicate that, besides different metal ions Co²⁺ and Zn²⁺ or OH^? anions, the steric hindrance of backbone ligands play an important role in the formation of I–III. Moreover, the luminescent properties of corresponding ligands and their complexes were briefly investigated.     

Synthesis and crystal structures of three novel coordination polymers generated from AgCN and AgSCN with flexible N-donor ligands

The solvothermal reactions of AgX (X = CN, SCN) with mbix [mbix = 1,3-bis(imidazole-l-yl-methyl)benzene] or bix [bix = 1,4-bis(imidazole-l-yl-methyl)benzene] afforded the polymers [AgCN(mbix)]_n (1), [(AgCN)₄(bix)₂]_n (2) and [(AgSCN)₂(mbix)]_n (3). They were all characterized by infrared spectroscopy, elemental analysis and X-ray single-crystal analysis. The structure of 1 contains a 3-fold-interpenetrated 2D network, while that of 2 exhibits 2-fold parallel interpenetration. There is no interpenetration observed in 3. Compounds 2 and 3 show 3D supramolecular structures built from 2D networks through weak π ? π interactions. The photoluminescent properties of the present compounds were also investigated.     

Synthesis, crystal structures and properties of four manganese coordination polymers with 4,4-bipyridine-derived ligands

Four new coordination polymers, namely Mn₂(4,4-bpy)₂(o-tol)₄ 1, Mn₂(4,4-bpy)₂(m-tol)₄ 2, Mn₂(bpp)₂(m-tol)₄ 3 and {[Mn₂(4,4-bpy)₂(p-tol)₄][Mn(4,4-bpy)₂(H₂O)₂(p-tol)₂]}·6H₂O 4 have been synthesized from 4,4′-bipyridine (4,4-bpy), 1,3-bis(4-pyridyl)-propane (bpp), o-toluic acid (o-Htol), m-toluic acid (m-Htol) and p-toluic acid (p-Htol). All four complexes feature dinuclear Mn₂(tol)₄ moieties, which are bridged by 4,4-bpy or bpp ligands to form 1D double-chain structures. The resulted 1D double-chains are assembled via hydrogen bonding or π···π stacking into 2D supramolecular layers. The complexes were characterized by physico-chemical (thermal behavior) and infrared spectroscopy. Variable temperature magnetic characterization suggest weak antiferromagnetic coupling exchange between dimeric Mn(II) centers (J = ?0.46 cm^?1 for 1, ?0.56 cm^?1 for 2, ?1.28 cm^?1 for 3 and ?0.59 cm^?1 for 4).     

三个包含四羧酸配体的配位聚合物的合成及其催化性质

利用水热合成方法,选用5-((3,5-二羧基苯基)氨基)苯-1,3-二甲酸配体(H₄adip)与菲咯啉(phen)、2,2′-联吡啶(bipy)或双(4-吡啶)胺(bpa),分别与 ZnCl₂和 CoCl₂·6H₂O 在 160 ℃温度下反应,合成了 3 个三维配位聚合物{[Zn₂( μ₆-adip)(phen)₂]·4H₂O}_n (1)、{[Co₂( μ₆-adip)(bipy)₂]·4H₂O}_n (2)和[Co₂( μ₄-adip)( μ-bpa)₂]_n (3)。这些配合物为稳定的晶体。通过红外光谱、元素分析、热重分析和单晶X射线衍射分析对其进行了表征。单晶X射线衍射分析表明,3个配合物的晶体属于正交晶系Pnna (1和2)和P2₁2₁2 (3)空间群。配合物 1~3都呈三维结构。考察了这些配合物在 Henry反应中的催化活性。研究表明,配合物 3在 70 ℃下对 Henry反应表现出有效的催化活性。同时对反应参数进行了优化,对底物范围也进行了研究。     

Synthesis, structures, luminescent and magnetic properties of four coordination polymers with the flexible 1,3-phenylenediacetate ligands

Four coordination polymers, [Zn(pda)(bpy)(H₂O)]_n·nH₂O (1), [Cd(pda)(prz)(H₂O)]_n (2), [Co₃(μ₃-OH)₂(pda)₂(pyz)]_n·2nH₂O (3) and [Pr₂(pda)₃(H₂O)₂]_n (4) (H₂pda=1,3-phenylendiacetic acid, bpy=4,4′-bipyridine, prz=piperazine and pyz=pyrazine) have been hydrothermally synthesized and characterized. Complex 1 is a 1D wheel-like chain structure, which is further extended into a 3D metal-organic supramolecular framework by H-bonds and π-π stacking interactions. Complex 2 is a 1D ladder-like chain structure, which is also further extended into a 3D metal-organic supramolecular framework by H-bonds. Complex 3 possess a 2D sheet structure with infrequent two pairs of double-helix chains. Complex 4 features a 3D structure. Both 1 and 2 display strong blue fluorescent emission at room temperature. Magnetic susceptibility measurements of complexes 3 and 4 exhibit antiferromagnetic interactions between the nearest metal ions, with C=9.99 and 3.43 cm³ mol⁻¹ K, and θ=−23.9 and −46.3 K, respectively.