One-dimensional Helical Chain Research Articles

Construction of one-dimensional homochiral helical supramolecular stereoismers using chiral macrocyclic nickel(II) complexes as building blocks

One one-dimensional right-handed helical chain of {[Ni(RR-L)][Ni(CN)4]·2H2O}n (Δ-2·(2H2O)n) was successfully constructed by the reaction of the [Ni(α-RR-L)]2+ and [Ni(CN)4]2− in acetonitrile/water (1:1) (L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane), and another two one-dimensional left-handed helical chains of {[Ni(SS-L)][Ni(CN)4]·2H2O}n (Λ-2·(2H2O)n) and {[Ni(SS-L)][Ni(CN)4]·1.25H2O}n (Λ-3·(1.25H2O)n) were obtained from the reaction of [Ni(α-SS-L)]2+ with [Ni(CN)4]2−. The reaction of [Ni(CN)4]2− building blocks with [Ni(α-SS-L)]2+ in acetonitrile/methanol (1:1) gave a one-dimensional left-handed helical chain of {[Ni(SS-L)][Ni(CN)4]·MeCN}n (Λ-2·(MeCN)n). In all supramolecular isomers, the [Ni(RR-L)]2+/[Ni(SS-L)]2+ cations are alternately bridged by [Ni(CN)4]2− anions through cyano-groups to form one-dimensional helical chains. The homochiral natures of four complexes were confirmed by the results of solid-state circular dichroism spectra measurements.

Structure, Luminescence, and Two-Dimensional Correlation Infrared Spectroscopy of Two Sm/3-Methylbenzoic Acid Complexes

Two samarium complexes with 3-methylbenzoic acid (HMeBA = 3-methylbenzoic acid) have been hydrothermally synthesized directly: Sm(MeBA)3 1 and Sm2(MeBA)6(o-Phen)2 2 (o-Phen = o-phenanthroline). 1 is a one-dimensional helical chain structure. In particular, due to the existence of the second ligand-o-Phen, which includes three aromatic rings and has very large steric hindrance, 2 is a zero-dimensional binuclear oligomer and is further assembled into an infinite chain, two-dimensional net and three-dimensional supramolecular structure by the weak interactions of π–π and C-H···π. Additionally, in order to explore the structural characteristic, luminescence and 2D-IR correlation spectroscopy containing temperature-induced structural variation and magnetism-induced structural variation are used. Supplementary material is available for this article. Go to the publisher's online edition of Synthesis and Reactivity in Inorganic, Metal-Organic, and Nano-Metal Chemistry to view the supplemental file.

Crystal Engineering with Modified 2-Aminopurine and Group 12 Metal Ions

This communication describes the synthesis and structure of zinc, cadmium, and mercury complexes of modified N9-substituted 2-aminopurine (2AP) analogues. 2AP is an inherently fluorescent heterocyclic nucleobase with wide applications in biochemical reactions. Herein, we report a one-dimensional (1D) polymeric helical chain and discrete arrangements for zinc complexes [C8H11N5Cl2Zn] (1) and [C12H15N5O5Zn] (2), a 1D polymeric helical chain for a Cd complex [C8H11CdI2N5] (3), and a unique example of supported 2AP-Hg(II) two-dimensional clusters [C16H21Cl6Hg3N10] (4). The photoluminescence properties of free ligand L and complexes 1–4 are also presented.

Synthesis, crystal structures, and fluorescence properties of two 1-D zinc(II) coordination polymers constructed from a bis(benzimidazole) ligand

[Zn(L)(HCOO)Cl]n (1) and {[Zn2(L)2(OH)(HCOO)Cl]·I}n (2) have been obtained by hydrothermal methods of zinc chloride with 1,3-bis(5,6-dimethylbenzimidazole-1-ylmethyl)benzene (L) and potassium bromide (or potassium iodide), and are characterized by elemental analysis, IR spectra, X-ray powder diffraction, and single-crystal X-ray diffraction. The zinc(II) centers display tetrahedral coordination in 1 and 2. Solid 1 forms a one-dimensional (1-D) helical chain bridged by L, which is further arranged into a two-dimensional supramolecular structure through intermolecular π–π stacking interactions. A 1-D ladder-like chain of 2 connected by hydroxyl and L is presented. Solid-state fluorescent properties of 1 and 2 have been investigated.

Synthesis, structural characterization and properties of a novel 1D helical chain arsenomolybdate {[Cu(en)2][Cu(en)(H2O)][(Cu(en)2(H2O)] [AsIIIAsVMo9O34)]}·2H2O

Abstract An organic–inorganic hybrid 1D helical chain arsenomolybdate {[Cu(en) 2 ][Cu(en)(H 2 O)][(Cu(en) 2 (H 2 O)] [As III As V Mo 9 O 34 )]} · 2H 2 O ( 1 ) (en = ethylenediamine) has been hydrothermally synthesized and characterized by elemental analyses, IR, UV and CD spectrum, powder X-ray diffraction, TG-DTA and single-crystal X-ray diffraction. The asymmetric unit of 1 consists of a monocapped trivacant Keggin [As III As V Mo 9 O 34 ] 6 − subunit, a pendant [Cu(en) 2 (H 2 O)] 2 + cation, a pendant [Cu(en)(H 2 O)] 2 + cation, one bridging [Cu(en) 2 ] 2 + cation and two lattice water molecules. It should be noted that 1 illustrates a one-dimensional (1D) helical chain assembled by {[Cu(en)(H 2 O)][(Cu(en) 2 (H 2 O)][As III As V Mo 9 O 34 )]} 2 − clusters and [Cu(en) 2 ] 2 + linkers.

A novel 1-D mixed-valence cobalt coordination polymer bridged with (μ-Oalkoxo) and (μ-carboxylate) units: Synthesis, structure and properties

A novel one-dimensional helical mixed-valence cobalt coordination polymer ( 1 ) {[Co II Co III (HL) 2 (OAc)]·CH 3 OH·H 2 O} n , ( H 3 L = 2-ethyl-2-((2-hydroxynaphthalen-1-yl)methyleneamino)propane-1,3-diol) has been synthesized and characterized. Single-crystal X-ray diffraction analyses reveal that complex 1 crystallizes in the tetragonal I4(1)/a space group. It consists of a bimetallic Co II Co III (μ 2 -O) 2 core, and the adjacent Co II (2) centers are sequentially bridged by carboxylate groups in the syn–anti fashion, affording to a one-dimensional infinite helical chain along the c -axis. Adjacent chains are stacked via C H···π interactions to form the overall three-dimensional supramolecular networks. Magnetic and in vitro anticancer activities of the complex have been investigated in detail. Susceptibility data for {[Co II Co III (HL) 2 (OAc)]·CH 3 OH·H 2 O} n in χ M T (○) vs. T (Δ). ► 1D mixed-valented cobalt coordination polymer are synthesized and characterized. ► Carboxylate groups bridge in the syn–anti fashion, leading to right-helice. ► Weak FM exchange interaction may occur in complex. ► In vitro anticancer activity of the complex are determined against A-549 cells.

Anion-directed organized assemblies of protonated pyrazole-based ionic salts

The reactions of 3(5)-(4-methoxyphenyl)-5(3)-phenyl-1H-pyrazole (L 1 ) with nitric acid and 5-(4-benzyloxyphenyl)-3-(furan-2-yl)-1H-pyrazole(L 2 ) with hydrochloric acid produced [HL 1 · NO3] (Salt-1) and [HL 2 · Cl] (Salt-2). The structures of Salt-1 and Salt-2 were determined by single crystal X-diffraction. In Salt-1, HL 1 showed [2 + 2] binding of NO3 − ions in the solid state to form dimer architecture with R 1 2 (4) and R 4 4 (14) graph sets. An anion directed one-dimensional anion-assisted helical chain with active participation of the chloride ion and protonated pyrazole via N–H···Cl hydrogen bonding in Salt-2. In addition, the protonated HL 2 molecules interacted with each other through weak C–H···π interactions resulting in the formation of another one-dimensional helical chain.

Syntheses and Characterization of Organotin(IV) Complexes Derived from 2-Mercapto-1,3,4-thiadiazole

Four organotin complexes of the types [(Ph3Sn)(C2HN2S2)] (1), [(CH3)3Sn(C2HN2S2)]n (2), [(Bu2Sn)(C2HN2S2)2] (3), and [(Me2Sn)4(C2HN2S2)2(µ 3-O)2(C2H5O)2] (4) have been obtained by 2-mercapto-1,3,4-thiadiazole and triorganotin chloride or diorganotin dichloride. All the complexes were characterized by elemental analysis, IR and NMR spectroscopy, and X-ray diffraction analyses, which revealed that complexes 1 and 3 are mononuclear structures, complex 1 can further form a one-dimensional (1D) helical chain, and complex 3 can further form a 22-membered macrocycle through the intermolecular C–H·N hydrogen bond; complex 2 is a 1D infinite chain linked by intermolecular NSn and SSn bonding interactions; complex 4 is a typical ladder structure. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 00:1–8, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21046

Synthesis, structure and luminescence of a hydrogen-bonding helical-chain Cu(II) compound based on (8-quinolinyloxy)acetate

A new compound of CuCl(QOA)(H2O) (1) [QOA = (8-quinolinyloxy)acetate] has been prepared and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. The crystal is of orthorhombic, space group P212121 with a = 5.364(1) A, b = 13.876(3) A, c = 15.435(3) A, V = 1,148.8(4) A3, Mr = 319.19, Dc = 1.846 g cm−3, Z = 4, F(000) = 644, μ = 2.138 mm−1, flack parameter = 0.00(17), the final R = 0.0311 and wR = 0.0646 for 2,179 observed reflections (I > 2σ(I)). Compound 1 consists of one-dimensional helical chains deriving from CuCl(QOA)(H2O) units linked by hydrogen bonds and further extend into a 3D supramolecular structure through Van der Waals interactions, and it exhibits strong luminescent emission at room temperature.

Assembly multi-dimensional CdII coordination architectures based on flexible bis(benzimidazole) ligands: Diversity of their coordination geometries and fluorescent properties

Based on three structurally related flexible bis(5,6-dimethylbenzimidazole) ligand, five novel metal–organic CdII coordination architectures: from 0D to 3D structures CdII complexes have been hydrothermally synthesized and structurally characterized, namely, Cd2I4(L1)2 (1), [CdCl2(L1)]n (2), [CdCl2(L2)]n (3), {[Cd(chdc)(L2)0.5]·H2O}n (4), {[Cd(pydca)(L3)0.5(H2O)2]·H2O}n (5) (where L1=1,2-bis(5,6-dimethylbenzimidazole)ethane, L2=1,3-bis(5,6-dimethylbenzimidazole)propane, L3=1,4-bis(5,6-dimethylbenzimidazole)butane, H2chdc=1,4-cyclohexanedicarboxylic acid, H2pydca=pyridine-2,6-dicarboxylic acid). A discrete binuclear [2+2] metallomacrocycles cadmium(II) complex of 1 is 0D, 3 and 5 exhibit one-dimensional helical and zigzag chain structures, respectively. 4 Forms a 2D layer with sql net topology bridged by carboxylate anion and L2, while 2 is an overall 3D array with the diamond topology (dia). In these complexes, the influences of anions coordination on the framework formation were observed and discussed. These results indicate the spacer length of the ligands and anions play important roles in controlling the diversity structural topologies of such metal–organic coordination architectures. The thermogravimetric analyses, X-ray powder diffraction and solid-state luminescent properties of the complexes have also been investigated.

Synthesis, Crystal Structure, and Characterization of a Novel One-Dimensional Helical Chain Cobalt(II) Coordination Polymer

A novel one-dimensional (1D) helical chain polymer, {[CoL2(H2O)](H3O)(ClO4)}n (1) (HL = 4-N-(2′-pyridylimine)benzoic acid), was synthesized by reaction of Co(II) perchlorate with L anion in ethanol solution, and characterized by element analyses, infrared spectroscopy, and X-ray single-crystal diffraction. In this structure, the Co2+ ion is in a distorted octahedral geometry, an infinite 1D helical chain was constructed by L ligand through bidentate-monodentate bridging modes and are further assembled into three-dimensional supramolecular networks through complicated O–H···O hydrogen bonding interactions.

End-to-End Thiocyanato-Bridged Helical Chain Polymer and Dichlorido-Bridged Copper(II) Complexes with a Hydrazone Ligand: Synthesis, Characterisation by Electron Paramagnetic Resonance and Variable-Temperature Magnetic Studies, and Inhibitory Effects on Human Colorectal Carcinoma Cells.

The reactions of the tridentate hydrazone ligand, N′-[1-(pyridin-2-yl)ethylidene]acetohydrazide (HL), obtained by condensation of 2-acetylpyridine with acetic hyadrazide, with copper nitrate trihydrate in the presence of thiocyanate, or with CuCl2 produce two distinct coordination compounds, namely a one-dimensional helical coordination chain of [CuL(NCS)]n (1) units, and a doubly chlorido-bridged dinuclear complex [Cu2L2Cl2] (2) (where L=CH3C(O)=N–N=CCH3C5H4N). Single-crystal X-ray structural determination studies reveal that in complex 1, a deprotonated hydrazone ligand L− coordinates a copper(II) ion that is bridged to two neighbouring metal centres by SCN− anions, generating a one-dimensional helical coordination chain. In complex 2, two symmetry-related, adjacent copper(II) coordination entities are doubly chlorido-bridged, producing a dicopper entity with a Cu⋅⋅⋅Cu distance of 3.402 (1) Å. The two coordination compounds have been fully characterised by elemental analysis, spectroscopic techniques including IR, UV–vis and electron paramagnetic resonance, and variable-temperature magnetic studies. The biological effects of 1 and 2 on the viability of human colorectal carcinoma cells (COLO-205 and HT-29) were evaluated using an MTT assay, and the results indicate that these complexes induce a decrease in cell-population growth of human colorectal carcinoma cells with apoptosis.

Four Three-Dimensional Coordination Polymers Constructed by 2-((1H-1,2,4-Triazol-1-yl)methyl)-1H-Imidazole-4,5-Dicarboxylate: Syntheses, Topological Structures, and Magnetic Properties

Hydrothermal reactions of Mn(II), Co(II), Cu(II), and Cd(II) salts with 2-((1H-1,2,4-triazol-1-yl)methyl)-1H-imidazole-4,5-dicarboxylic acid (H3tmidc) lead to four novel coordination polymers, namely, [Mn3(tmidc)2(H2O)4]·(H2O)6 (1), [Co3(tmidc)2(H2O)4]·(H2O)4 (2), [Cu3(tmidc)2(H2O)]·(H2O) (3), and [Cd(Htmidc)] (4). Compound 1 has a three-dimensional (3D) architecture, and the topological study shows that its framework features a 3D (3,4)-connected fsc-3,4-Pbca network with the Schläfli topological symbol of (63)(63.83). Compound 2 exhibits a 3D pillared framework constructed by 4-fold one-dimensional (1D) helical chains and possesses open helical channels in the framework. Topological analysis reveals that it is a unique (3,4)-connected net with the Schläfli symbol of (4.52)(4.5.114) which is not enumerated in RCSR andTOPOS, and has not been reported in the literature. Compound 3 features a 3D intricate framework displaying a new (3,4)-connected 4-nodal net with the Schläfli symbol of (5.72)(4.5.7)(52.72.8.10)(4.5.73.8) which has not been observed in any other coordination polymers. Topological analysis of the 3D network found in compound 4 reveals that the whole structure can be rationalized as a (4.65)(4.65) crb topological net.

Poly[aqua[μ3-(pyridin-1-ium-3,5-diyl)diphosphonato-κ3O:O′:O′′][μ2-(pyridin-1-ium-3,5-diyl)diphosphonato-κ2O:O′]calcium(II)

The rigid organic ligand (pyridine-3,5-diyl)diphosphonic acid has been used to create the title novel three-dimensional coordination polymer, [Ca(C(5)H(6)NO(6)P(2))(2)(H(2)O)](n). The six-coordinate calcium ion is in a distorted octahedral environment, formed by five phosphonate O atoms from five different (pyridin-1-ium-3,5-diyl)diphosphonate ligands, two of which are unique, and one water O atom. Two crystallographically independent acid monoanions, L1 and L2, serve to link metal centres using two different coordination modes, viz. η(2)μ(2) and η(3)μ(3), respectively. The latter ligand, L2, forms a strongly undulated two-dimensional framework parallel to the crystallographic bc plane, whereas the former ligand, L1, is utilized in the formation of one-dimensional helical chains in the [010] direction. The two sublattices of L1 and L2 interweave at the Ca(2+) ions to form a three-dimensional framework. In addition, multiple O-H···O and N-H···O hydrogen bonds stabilize the three-dimensional coordination network. Topologically, the three-dimensional framework can be simplified as a very unusual (2,3,5)-connected three-nodal net represented by the Schläfli symbol (4·8(2))(4·8(8)·10)(8).

Spontaneous resolution of a coordination polymer containing stereogenic five-coordinate Zn(ii) centers and achiral ligands with axially chiral conformation

A pair of chiral coordination polymers, [Zn(HPyIDC)]n (1a and 1b, H3PyIDC = 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate), were assembled from an achiral precursor, H3PyIDC and Zn(II) ions via spontaneous resolution under solvothermal conditions. Crystal structure analysis showed that they are chiral three-dimensional (3D) coordination polymers based on the interconnection of six types of one-dimensional (1D) helical chains. They exhibit an intrinsic chiral (10,3)-a network. The chirality comes from both the stereogenic five-coordinate Zn(II) ions and the axially chiral ligands. Solid-state circular dichroism (CD) spectra measurements confirmed the occurrence of spontaneous resolution of [Zn(HPyIDC)]n and demonstrated that the resulting crystal of [Zn(HPyIDC)]n is a racemic mixture. Compound 1 showed strong fluorescence emission at room temperature.

Anion effect on the structural diversity of three 1D coordination polymers based on a pyridyl diimide ligand

Three new zinc coordination polymers, namely {[Zn(4-pmntd)Cl2]·H2O}n (1), {[Zn(4-pmntd)(CH3CN)4]·(ClO4)2·H2O}n (2), and {[Zn(4-pmntd)(H2O)4]·(CF3SO3)2·3H2O}n (3) (4-pmntd = N,N′-bis(4-pyridylmethyl)-naphthalene diimide) have been synthesized by reactions of 4-pmntd with ZnCl2, Zn(ClO4)2, and Zn(CF3SO3)2, respectively. Compound 1 is an unusual one-dimensional (1D) single-stranded double helical chain containing tubular channels; 2 is an uncommon 1D zigzag chain arranged in a cross-like fashion to generate a 3D plywood-like array; 3 is a typical 1D zigzag chain arranged in a parallel array containing 1D quadrangle channels to accommodate the counter anions and water molecules. The structural diversity in these compounds is attributed to different coordination abilities, sizes, and geometries of counter anions. The anion exchange property of 3 was investigated.

Synthesis, structures and luminescent properties of cadmium(ii) metal organic frameworks based on 3-pyrid-4-ylbenzoic acid, 4-pyrid-4-ylbenzoic acid ligands

Two three-dimensional metal–organic frameworks, [Cd3K(L1)6(H2O)3](OH)(DMF)4 (1) (HL1 = 3-pyrid-4-ylbenzoic acid) and [Cd(L2)2](DMF)(H2O)0.25 (2) (HL2 = 4-pyrid-4-ylbenzoic acid), have been synthesized by using two ligands with different configuration and characterized by X-Ray diffraction and other techniques. Compound 1 shows a nanosize channel which is constructed by interlocked six-fold one-dimensional helical chains with the asymmetrical ligand HL1. Compared with compound 1, compound 2 shows a larger size channel with the symmetrical ligand HL2 in a single set of diamond cage. Nevertheless, the whole structure with the 4-fold interpenetrated diamondoid network leads to the absence of void space. The two compounds exhibit fascinating luminescence because of the interaction between Cd ions and organic ligands.

A novel chiral helical coordination complex with Ferroelectric and Weak Ferromagnetic properties

A novel chiral copper-based complex constructed from chiral ligand, namely [Cu(L)(H 2 O)]·H 2 O ( 1 ) (L = (S)-3-phenyl-2-(pyrazine-2-carboxamido) propanoic acid). Complex 1 was prepared through solvothermal reactions and characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in the tetragonal system with non-centrosymmetric polar space group P 4 3 and affords one-dimensional (1D) chiral helical chain. Ferroelectric and magnetic studies reveal that 1 shows both ferroelectric and weak ferromagnetic properties. A novel chiral copper-based complex crystallizes in the tetragonal system with non-centrosymmetric polar space group P 4 3 and affords one-dimensional (1D) chiral helical chain. Ferroelectric and magnetic studies reveal that 1 shows both ferroelectric and weak ferromagnetic properties. ► Crystallizes in the tetragonal system with non-centrosymmetric polar space group P 4 3 and affords one-dimensional (1D) chiral helical chain. ► The adjacent helical chains are linked by intermolecular hydrogen bonds, generating a 3D supermolecular network. ► Ferroelectric and magnetic measurements show both ferroelectric and weak ferromagnetic properties.

Syntheses, Structure, and Photoluminescent and Thermal Properties of a Novel Coordination Polymer [CuI(3-bpfob)]n with One-Dimensional Helical Chain

Solution reaction of CuI and the ligand L((3-bpfob) [L: 1,3-bis(nicotinoyl) o-phenylenediamine] led to the formation of a novel coordination polymer [CuI(3-bpfob)]n that exhibited an unusual one-dimensional helical structure. The compound was characterized by x-ray crystallography, infrared (IR) spectroscopy, fluorescence spectrum, and thermal analyses. This compound crystallized in triclinic system, space group P-1, with cell parameters of a = 7.940(5), b = 10.187(6), c = 12.518(7) Å, α = 78.041(6)°, β = 72.821(6)°, γ = 72.821(6)°.

Assembly of anion-controlled cadmium(II) coordination polymers based on flexible bis(imidazole) derivative

Four Cd(II) metal–organic complexes, namely, [Cd(Cl)2(bbdmbm)] (1), [Cd(NO3)(N3)(bbdmbm)1.5] (2), [Cd(BBA)2(bbdmbm)(H2O)] (3), [Cd(DNBA)2(bbdmbm)] (4), (bbdmbm=1,1-(1,4-butanediyl)bis(5,6-dimethylbenzimidazole), HBBA=4-bromobenzoic acid, and HDNBA=3,5-dinitrobenzoic acid) have been obtained from hydrothermal reactions of different Cd(II) salts with the mixed ligands of bbdmbm and five anions (Cl−, NO3−, N3−, BBA and DNBA). Single crystal X-ray diffraction analyses reveal that the four complexes exhibit different structures. Complex 1 possesses a one-dimensional (1D) helical chain, which is finally extended into a two-dimensional (2D) supramolecular structure through π–π stacking interactions. Complex 2 shows a 1D ladderlike chain bridged by bbdmbm ligands with two kinds of coordination conformations. Complex 3 is a 1D coordination polymer and is ultimately extended into a 2D supramolecular network through H-bonding interactions. Complex 4 displays a dinuclear cluster, which is finally packed into a three-dimensional (3D) supramolecular framework through three kinds of π–π stacking interactions. The Cd(II) exhibits four different coordination modes in complexes 1–4, respectively. The results indicate that the anion ligands with different steric hindrance and size play important roles in the coordination modes of Cd(II) and construction of the title complexes, leading to the structural diversity. In addition, the conformations of bbdmbm ligand also show some effect on the final structures. Fluorescence properties of complexes 1–4 are reported in this paper.