Double-chain Coordination Polymer Research Articles

Cunning defects: emission control by structural point defects on Cu(i)I double chain coordination polymers

We present two new coordination polymers based on double Cu(i)–I chains, with identical structure. Variations in the synthesis conditions lead to the formation of defects which strongly affect the optical properties of these compounds.

Highly efficient 3d/4d-4f coordination polymer catalysts for carbon dioxide fixation into cyclic carbonates.

Two novel highly efficient 3d/4d-4f one-dimensional (1D) double-chain coordination polymer catalysts with unique structures were synthesized for the first time. An X-ray single crystal structure analysis revealed that the two compounds are isomorphous and have a 1D metal-organic network coordination polymer structure. Both compounds also showed significant thermal stability and their structures remained stable up to 325 °C. The reaction conditions, type of substrate, amount of catalyst and its catalytic mechanism were investigated. The catalysts ([Dy2M2L4 (OAc)2 (MeOH)5 (H2O)]) (M = Zn, Cd) exhibited excellent catalytic activity in the cycloaddition of CO2 and styrene oxide (C8H8O, SO). High product yields, high selectivity, and the highest turnover frequency (TOF) of 28 400 h-1 were achieved. Additionally, the catalysts can significantly enhance the application of the present types of 3d/4d-4f catalysts in catalysis for transformations involving the fixation of CO2.

Synthesis, characterization and antimicrobial activities of triorganotin(IV) complexes with azo-azomethine carboxylate ligands: crystal structure of a tributyltin(IV) and a trimethyltin(IV) complex

Triorganotin(IV) complexes with polyaromatic azo-azomethine carboxylate ligands viz. 2-{4-hydroxy-3-[(2/4-hydroxyphenylimino)methyl]phenylazo}benzoic acids [H3L1/H3L2] were synthesized by reacting the ligands with either bis-tri-n-butyltin(IV) oxide (for 1 and 4) or trimethyltin(IV) chloride in presence of triethylamine (for 2 and 5) or triphenyltin(IV) hydroxide (for 3 and 6). The complexes were characterized by elemental analysis, UV, IR, NMR, and mass spectrometry. NMR spectroscopic studies of the compounds suggested that the complexes adopt four-coordinate tetrahedral geometry around tin in solution. Molecular structures of 1 and 2 were determined by single-crystal X-ray diffraction. Both complexes have distorted trigonal bipyramidal geometry around tin in the solid state. Compound 1 is a one-dimensional (1-D) double chain coordination polymer which can be described as two different 24- and 30-membered non-porous macrocyclic rings constructed from two tributyltin units and two ligand moieties. The structure of 2 comprises a discrete cyclic centrosymmetric dimer with two lattice water molecules per formula unit. In the dimer, two trimethyltin entities are bridged by two ligand moieties. The dimers are further interconnected with lattice water molecules by multiple O–H⋯O hydrogen bonds to form a 1-D H-bonded network. The complexes were also screened for their antimicrobial activities.

Supramolecular interactions in double-chain coordination polymers based on copper(I) cations with chiral linkers

Two double-chain chiral coordination polymers [CuI2(bpy)2(phlac)](NO3)·H2O (1) and [CuI2(bpy)2(clman)](NO3)·H2O (2) were obtained by heating a DMF/H2O solution of copper(II) nitrate, 4,4′-bipyridyl (bpy), S-3-phenyllactic (Hphlac) or R-3-chloromandelic (Hclman) acid. The compounds were structurally characterized by X-ray crystallography.

Two new Pb(II) coordination polymers derived from fatty dicarboxylates and phenanthroline derivatives: syntheses, structures, and properties

Two new Pb(II) coordination polymers, [Pb(3-pdip)(L1)] · 0.5H2O (1) and [Pb(4-pdip)(L2)] (2) [L1 = heptane diacid, L2 = hexane diacid, 3-pdip = 2 -(3-pyridyl)imidazo[4,5-f]1,10-phenanthroline, 4-pdip = 2 -(4-pyridyl)imidazo[4,5-f]1,10-phenanthroline], have been obtained from hydrothermal reactions of Pb(II) nitrate with two flexible fatty carboxylic acids and two phenanthroline derivatives. Single-crystal X-ray diffraction analysis reveals that 1 is a 1-D staircase-like double chain coordination polymer extended by binuclear [Pb2N4O8] subunits and pairs of L1 ligands. Compound 2 exhibits a 2-D (4,4) network based on bi-metallic [Pb2N6O8] units and (L2)2/(4-pdip)2 double linkers. Furthermore, adjacent chains of 1 and layers of 2 are extended into 3-D supramolecular networks by π–π stacking interactions between aromatic rings of phenanthroline groups. The organic carboxylic acids with different lengths show great influence on the shapes of Pb(II)-carboxylate double chains. Phenanthroline derivatives possessing different sites of N-donors (3-pyridyl and 4-pyridyl) determine the final coordination frameworks of 1 and 2. Photoluminescence and thermal stabilities of 1 and 2 were also investigated.

Syntheses, crystal structures and properties of lanthanide complexes featuring infinite molecular rectangle strands constructed from a new macrocyclic metalloligand

Three new double-chain coordination polymers {[Pr(NiL1)2(H2O)3](ClO4)3·2H2O}∞ (1), {[Sm(NiL1)2(H2O)3](ClO4)3·2H2O}∞ (2) and {[Gd(NiL1)2(H2O)3](ClO4)3·2H2O}∞ (3) were prepared and structurally characterized by X-ray single-crystal analyses. L1 denotes the doubly deprotonated form of 2-hydroxyethoxyethyl 5,6,7,8,15,16-hexahydro-6,7-dioxodibenzo[1,4,8,11]tetraazabicyclo[12.4.015,16]-13,18-dicarboxylate. The new mononuclear macrocyclic complex NiL1 acts as the bridging ligand with a monodentate coordination top (one of the alcohol hydroxyls) and a bidentate one (the oxamido carbonyls) between two Ln(III) (Ln=Pr, Sm and Gd in 1, 2 and 3, respectively) nodes to enclose the rectangular Ln2(NiL1)2 subunits. Most of the corresponding metal-to-metal distances in the subunits of the three compounds decrease following the variation trend identical to that of the ionic radii of Pr(III), Sm(III) and Gd(III). The studies with plasmid DNA showed that 1, 2 and 3 induced DNA cleavage. Luminescence investigation displayed that no emission occurred for the three coordination polymers in DMF at room temperature.

Tuning 1-D Pb(II) Coordination Polymers by Flexible and Semirigid Dicarboxylates: Synthesis, Structure and Properties

Two new one-dimensional (1-D) Pb(II) coordination polymers, namely, [Pb(3-pdip)(L1)]·H2O (1) and [Pb(3-pdip)(L2)] (2) [L1H2 = 1,6-hexanedioic acid, L2H2 = homophthalic acid, 3-pdip = 2-(3-pyridyl)imidazo[4,5-f]1,10-phenanthroline] have been obtained from hydrothermal reactions of Pb(II) nitrate with the phenanthroline derivative and the two dicarboxylic acids. Single-crystal X-ray diffraction analysis reveals that compound 1 is a staircase-like double-chain coordination polymer constructed from binuclear [Pb2N4O8] subunits and pairs of [L1]2− anions. Compound 2 is a linear coordination polymer connected via two μ2-η2:η1 carboxylate groups from [L2]2− anions. Furthermore, adjacent chains of 1 and 2 are extended into 3-D supramolecular networks by hydrogen bonds and π-π stacking interactions. The organic carboxylic acids with different flexibility determine the structures of the coordination polymers. Moreover, the thermal stabilities and photoluminescence properties of compounds 1 and 2 were investigated.

1-D zigzag double-chain coordination polymers of transition metals derived from pyridine-2,3,5,6-tetracarboxylic acid

Three new 1-D zigzag coordination polymers {[M2(pdtc)(bpy)2(H2O)3] · 4H2O} n [M = Zn (1), Ni (2), Co (3)] (H4pdtc = pyridine-2,3,5,6-tetracarboxylic acid, bpy = 2,2′-bipyridine) have been synthesized by the reactions of H4pdtc and corresponding metal salts in the presence of bpy at room temperature and characterized by elemental analyses, IR, TGA, fluorescence, and X-ray diffraction. The main structural feature of 1–3 is the presence of octahedrally coordinated M1(II) and M2(II) centers sequentially bridged by pdtc ligands; bpy acts as a blocking ligand to avoid further polymerization. These coordination modes lead to 1-D double-chain structures. The 2-D or 3-D supramolecular structures of 1–3 are built up by π ··· π and hydrogen-bond interactions. Two (H2O)3 clusters are observed in 1–3. The zinc complex shows strong fluorescent emission at 325 nm.

A zipper-like double chain coordination polymer constructed from a novel pseudo-macrocyclic binuclear Cu(II) complex

Abstract A novel coordination polymer [Cu2(HL)(CH3OH)(ClO4)]n(ClO4)n (1) has been synthesized from a multihydoxy Schiff base ligand, 1,3-bis(salicylidene iminoethylamino)-2-propanol (H3L). Single crystal X-ray diffraction analyses reveal that the coordination polymer is comprised of binuclear units, wherein the copper centers are bridged by a single alkoxo group, with a large bridging angle of 135.06°. By the linkage of an intramolecular hydrogen bond, an interesting pseudo-macrocyclic structure is formed. The binuclear moieties are assembled into a 1-D chain by the linkage of axially coordinated ClO4− anions, and the 1-D chains are further connected via intermolecular C-H⋅⋅⋅π stacking interactions, affording a zipper-like double chain supramolecular structure. Variable-temperature magnetic data measurements and analyses show the existence of strong antiferromagnetic interaction between the copper centers within the binuclear unit, mediated by the single alkoxo bridge with a − 2J value of 545 cm− 1.

Synthesis, structures and thermal stabilities of three 1-D coordination polymers based on flexible polycarboxylates

Three new coordination polymers, [Cu(butca)0.5(bipy)(H2O)] n · 2nH2O (1), [Zn(H2butca) (phen)(H2O)] n · nH2O (2), and [Cd(H2chhca)0.5(phen)(H2O)] n · 2nH2O (3) (H4butca =1,2,3,4-butanetetracarboxylic acid, H6chhca = 1,2,3,4,5,6-cyclohexanehexacarboxylic acid), were prepared and characterized by EA, IR, TG, and X-ray crystallography. Complex 1 is a 1-D double-chain coordination polymer in which tetradentate butca4− coordinates to four Cu(II) ions through four monodentate carboxylates. Complex 2 is a 1-D chain with tridentate H2butca2− coordinating to two Zn(II) ions through monodentate and chelating carboxylates. Complex 3 is a 1-D double-chain coordination polymer. H2chhca4− is octadentate coordinating to four Cd(II) ions through four chelating carboxylates. Hydrogen bonds and π–π stacking interactions play important roles in the formation of supramolecular architectures. The thermal stabilities of 1–3 show dehydrated coordination polymers are thermally stable in the range 260–400°C.

Double chains-copper(I)-based coordination polymer with strong blue fluorescent emission

A solvothermal reaction of Cu(CN) with triphenylphosphine yielded a double-chain coordination polymer of the formula C20H15Cu2N2P (I). X-ray diffraction study shows that complex I crystallizes in the monoclinic system, space group P21/n, with lattice parameters a = 9.3017(8), b = 12.4273(13), c = 16.0505(15) A, β = 91.688(6)°, V = 1854.6(3) A3, Z = 4, and ρcalcd = 1.581 mg m−3. The Cu(I) atoms show difference in the coordination environment. Complex I emits strong blue fluorescence light (λem(max) = 516 nm), when it is excited by the UV light (λexc(max) = 250 nm) in the solid state at room temperature.

Structures and luminescent properties of a series of Ln–Ag heterometallic coordination polymers

Eight new 4f–4d heterometallic coordination polymers have been synthesized using pyridine-2,6-dicarboxylic acid (H2PDA) as ligand under hydrothermal conditions. {[PrAg(PDA)2(H2O)3]·2.5H2O}n (1) comprises a 2D grid-like net, and the grid structure is assembled through a Pr4Ag2 motif as the building block. The subsequent six complexes [LnAg(PDA)2(H2O)3]·3H2O}n (Ln = Ce3+, 2; Nd3+, 3; Sm3+, 4; Eu3+, 5; Tb3+, 6; Dy3+, 7) are 1D double-chain coordination polymers. In 2–7, the Ln3+ and Ag+ ions are linked by carboxylic O bridges to form the helical chains, while the right-handed and left-handed chains are linked through carboxylic O bridges to form the double-helical chain. Additionally, the lattice H2O molecules linked by hydrogen bonds construct the helical water chain. {[CeAg2(PDA)3(Py)4]·H2O}n (8) (Py = pyridine) contains one Ce4+ ion and displays a 1D wave-like chain, in which partial H2PDA ligands were decomposed to pyridine. Luminescent studies reveal that the emission intensity of 7 significantly increases with the introduction of Mg2+ ions into the system of 7, whereas the addition of other metal ions causes emission intensity to remain the same or even decrease. Therefore, complex 7 may serve as a luminescent probe of Mg2+.

Catena-Poly[[bis(μ-3-carboxybenzoato)bis(1,10-phenanthroline)tricopper(II)]-di-μ3-isophthalato

The title copper coordination polymer, [Cu3(C8H4O4)2(C8H5O4)2(C10H8N2)2]n, was synthesized by reacting Cu(NO3)2, isophthalic acid and 1,10-phenanthroline under hydro­thermal conditions. The trinuclear unit presents a central almost planar CuO4 chromophore with the cation on a symmetry center, and two symmetry-related CuN2O3 groups with the metal centre in a distorted square-pyramidal environment. These units are bridged by isophthalate ligands into one-dimensional double-chain coordination polymers which are, in turn, connected by various π–π stacking inter­actions (face-to-face distance ca 3.45 Å) and O—H⋯O hydrogen bonds, forming a three-dimensional supra­molecular network.

Hg(μ-4,4′-bipy)(μ-AcO)(AcO)] n · n/2H 2O, one-dimensional double-chain coordination polymer, syntheses, characterization, thermal, fluorescence, porous and structural studies

A new Hg II coordination polymer with 4,4′-bipyridine and acetate anions, [Hg(μ-4,4′-bipy)(μ-AcO)(AcO)] n · n/2H 2O ( 1), has been synthesized, characterized by elemental analysis, IR-, 1H NMR-, 13C NMR spectroscopy and its structure determined by single-crystal X-ray diffraction. The thermal stability of compound 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The structural studies of compound 1 show that the structure may be considered as a coordination polymer of mercury(II) consisting of linear double chains formed by a bridging 4,4′-bipy ligand and by connecting acetate-bridged centrosymmetric {Hg 2(OAc) 2} 2+ nodes. Solid-state luminescent spectra of the ligand 4,4′-bipyridine and compound 1 indicate a fluorescent broad emission band with the maximum intensity at ca 468.2 and 446.4 nm upon excitation at 295 nm, respectively. The stability of porous network after removal of guest water molecules is not confirmed by X-ray powder diffraction.

Hydrothermal syntheses, crystal structures and magnetic properties of two copper(ii) complexes involved in situ ligand synthesis

The hydrothermal reaction of Cu(NO(3))(2), isophthalate (ip) and 2,2'-bipyridine (2,2'-bpy) without or with K(2)Cr(2)O(7) affords different complexes, whose structures are controlled only by the addition of the K(2)Cr(2)O(7). The reaction of Cu(NO(3))(2), isophthalate and 2,2'-bipyridine yields a novel one-dimensional double-chain coordination polymer [Cu(3)(ip)(2)(Hipa)(2)(bpy)(2)](n) (1). However, with the addition of K(2)Cr(2)O(7) in the above reaction at the same hydrothermal conditions, a discrete hexanuclear Cu(II) complex [Cu(6)(ipO)(4)(2,2'-bpy)(2)(H(2)O)(2)].6H(2)O (2) (ipOH = 2-hydroxyisophthalate) was isolated. It is interesting to find that the in situ reaction of isophthalate (ip) oxidized to 2-hydroxyisophthalate (ipOH) occurs. K(2)Cr(2)O(7) acts as an oxidant. The magnetic properties of 1 and 2 have been investigated by variable-temperature magnetic susceptibility and magnetization measurements, and the results reveal that intramolecular ferromagnetic interactions exist with weak intermolecular antiferromagnetic interactions at very low temperature in 1 and weak antiferromagnetic interactions admixture with strong ferromagnetic interactions in 2.

Temperature effect on the conversions of phthalato and maleato manganese(II) complexes with diamine ligands

1,10-Phenanthroline hydrogen phthalato manganese(II) dimer [Mn 2(Hphth) 2(phen) 4] · 2Hphth · 6H 2O ( 1), monomeric phenanthroline phthalato manganese(II) monomer [Mn(phth)(phen) 2(H 2O)] · 2.5H 2O ( 2), 2,2′-bipyridine phthalato manganese(II) polymer [Mn(phth)(bpy)(H 2O) 2] n ( 3) and 1,10-phenanthroline maleato polymer [Mn(male)(phen)(H 2O) 2] n · 2 nH 2O ( 4) (H 2phth = o-phthalic acid, male = maleic acid, phen = 1,10-phenanthroline and bpy = 2,2′-bipyridine) have been synthesized and characterized spectroscopically and structurally. Each Mn(II) atom in dimeric 1 is octahedrally coordinated by two oxygen atoms of phthalate anions and by two cis-phenanthroline ligands. The hydrogen phthalato anion bridges the Mn(II) ions through the deprotonated carboxyl groups, while the carboxylic acid group remains free. In the monomeric 2, the Mn(II) ion is octahedrally surrounded by four nitrogen atoms from two cis-phen ligands, one carboxyl oxygen from a monodentate phth ion, and one coordinated water molecule. The dimeric phthalato complex 1 can be cleaved into monomer 2 under heating with deprotonation, and the course of the reaction can be qualitatively traced by IR spectra. The phthalate group in the complex 3 binds to two manganese atoms through the vicinal carboxyl-oxygen atoms in syn– syn bridging mode. The Mn(II) atoms are linked by the phthalate group to yield a one-dimensional chain running along the a-axis. The coordination polymer 3 can be obtained from the reaction of dichloro dibipyridine manganese with phthalate under heating. In polymer 4, the manganese atom is six-coordinated by two nitrogen atoms from phen, two oxygen atoms from the coordinated water molecules and two oxygen atoms from two different maleate dianions. Each maleato unit links two neighboring manganese atoms to yield one-dimensional chain along b-axis in bis-monodentate mode. The single-chain polymer 4 prepared at low temperature can be converted to double-chain coordination polymer [Mn(male)(phen)] n · nH 2O ( 5) with dehydration in warm solution.

Crystallographic report: a double chain coordination polymer: {[Zn(H2O)6][Zn(3,3′,4,4′‐benzophenonetetracarboxylate)H2O]·4H2O}n

AbstractThe double‐chain coordination polymer, {[Zn(H2O)6][Zn(bbtc)H2O]·4H2O}n (bbtc = 3,3′, 4,4′‐benzophenonetetracarboxylate), features two kinds of zinc center. One is octahedrally coordinated by six aqua ligands and the other is coordinated by four carboxylate oxygen atoms, derived from three bbtc ligands, and a water molecule, forming a geometry intermediate between square‐pyramidal and trigonal bipyramidal. Copyright © 2003 John Wiley & Sons, Ltd.