Mn Coordination Polymers Research Articles

Exploratory syntheses, crystal structures, and properties of two new 3-D coordination polymers of Mn(II) and Fe(II) with (54.62) (510.63.7.8) topological spaces

Solvothermal reactions of terphenyl-2,5,2′,5′-tetracarboxylic acid (H4qptc) and MII (M = Mn, Fe) in the presence of 1,2-bis(diphenylphosphino)ethane (dppe) afford two new coordination polymers, [M(qptc)(dppe-O)] n (M = Mn (1), Fe (2)) (1,2-bis(diphenylphosphoryl)ethane = dppe-O). The structures have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR, TGA, and magnetism. The MII in 1 and 2 are linked by qptc4− to form 2-D layers, which are further connected via the oxidized dppe (dppe-O) exhibiting a (4,6)-connected network with the (54.62)(510.63.7.8) topology.

Synthesis, Crystal Structure and Magnetic Properties of a Porous Manganese Coordination Polymer with N-[(4-Carboxyphenyl)-sulfonyl]glycine and 4,4′-dipyridyl

A new Mn coordination polymer, [Mn(cbsglyH)(bipy) (H2O)] n ·nH2O (1) (cbsglyH3 = N-[(4-carboxyphenyl)-sulfonyl] glycine], bipy = 4,4′-dipyridyl), was prepared by aqueous reactions of Mn(II) acetate with cbsglyH3 in the presence of 4,4′-dipyridyl co-ligand. Its crystal structure was determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses and IR spectra. In 1, cbsglyH3 link the Mn(II) ions to form 2D layers that are held together through 4,4′-dipyridyl molecules in a double-pillar supporting fashion to give a 3D porous framework. Moreover, the magnetic properties of the title complex were investigated and are discussed in detail.

Three-dimensional networks based on trinuclear motifs with tricomponent azide-carboxylate-tetrazolate cobridges: synthesis, structure and magnetic properties

Two 3D coordination polymers of Mn(II) with azide and bifunctional zwitterionic ligands bearing both carboxylate and tetrazolate groups, 1-(carboxylatomethyl)-3-(5-tetrazolato)pyridinium (L(1)) and 1-(carboxylatoethyl)-4-(5-tetrazolato)pyridinium (L(2)), were synthesized, and structurally and magnetically characterized. They are formulated as [Mn(3)(L(1))(2)(N(3))(4)(H(2)O)(2)](n)·4nH(2)O (1) and [Mn(3)(L(2))(2)(N(3))(4)(H(2)O)(3)](n)·3.5nH(2)O (2). In both compounds, octahedral Mn(II) ions are linked by the mixed (μ(2)-EO-N(3))(μ(2)-syn,syn-COO)(μ(2)-N(2),N(3)-CN(4)) (CN(4) = tetrazolate and EO = end-on) triple bridges to give anionic linear trinuclear motifs. The motifs are connected through EE-N(3) (EE = end-to-end) bridges to give layers and chains in 1 and 2, respectively, and the cationic pyridinium spacers serve to interlink the layers or chains into three-dimensional frameworks with the α-Po and CdSO(4)-type topology, respectively. Magnetic studies demonstrated that the magnetic interactions within and between the trinuclear motifs, through the tricomponent and EE-N(3) bridges, respectively, are both antiferromagnetic in both compounds.

A new linking ligand with pyridyl–carboxylate terminals and its coordination polymers: Synthesis, structures, and properties of H L, [Ag L] ∞, {[Cd L2](CH 3OH)(H 2O)} ∞, and [Mn L2(CH 3OH)] ∞ { L = (3-py)–CH [dbnd]N–CH 2–C 6H 4–COO}

A new linking ligand with pyridyl–carboxylate terminals {H L = (3-py)–CH N–CH 2–C 6H 4–COOH} was prepared from 3-pyridinecarboxaldehyde and 4-(aminomethyl)benzoic acid by Schiff-base condensation. Under solvothermal conditions in methanol, the ligand reacted with AgBF 4, Cd(NO 3) 2·4H 2O, and Mn(OAc) 2·4H 2O to produce a 3-D Ag coordination polymer [Ag L] ∞ ( 1), a 2-D Cd coordination polymer {[Cd L 2](CH 3OH)(H 2O)} ∞ ( 2), and a 2-D Mn coordination polymer [Mn L 2(CH 3OH)] ∞ ( 3), respectively. In all coordination polymers, both the terminal pyridyl and terminal carboxylate groups in the ligand coordinate to metal ions to form coordination polymers. The central imine nitrogen in the ligand coordinates to the metal ion (Ag +) in coordination polymer 1, but it does not coordinate to the metal ions in coordination polymers 2 and 3. Coordination polymer 2 contains guest molecules (water and methanol molecules), whereas coordination polymers 1 and 3 do not.

Seven Coordinated Metal Complexes derived from (3-Carboxymethoxy-Naphthalen-2-yloxy)-Acetic Acid and Coordination Polymers

A design principle for seven coordinated metal carboxylate complexes and coordination polymers of Mn(II), Cd(II) and Na(I) derived from (3-carboxymethoxy-naphthalen-2-yloxy)-acetic acid (LH2) is presented. The complexes/coordination polymer [Mn(L)(H2O)3]·3H2O (1), [{Cd(L)(H2O)2}·H2O]n (2); [Cd(L)(py)3]·3H2O (3) have metal ions in pentagonal bipyramid environments (py = pyridine). The coordination polymer [{Cd(L)(H2O)2}·H2O]n (2) may be considered to be the self-assembly of hexacoordinated [Cd(L)(H2O)2] units; it reacts with pyridine to form mono-nuclear complex 3. Depending on the reaction conditions, Ni-coordination polymers of L adopt different compositions. From the reaction carried out with NiCl2 and NaOH in quinoline and water, a hetero bimetallic coordination polymer; namely, [[NaL(H2O)]2Ni(H2O)4]n (4) is obtained. A similar reaction in pyridine-water solvent led to [{Ni(L)(py)3}.py]n (5). The coordination polymer 5 has pyridine in its interstices held by C–H···π interactions.

Antimicrobial agents: synthesis, spectral, thermal, and biological aspects of a polymeric Schiff base and its polymer metal(II) complexes

Some new coordination polymers of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) obtained by the interaction of metal acetates with polymeric Schiff base containing formaldehyde and piperazine have been investigated. Structural and spectroscopic properties have been studied by elemental, spectral (FT-IR, 1H-NMR, and UV-Vis), and thermogravimetric analysis. UV-Vis spectra and magnetic moments indicate that Mn(II), Co(II), and Ni(II) polymer metal complexes are octahedral, while Cu(II) and Zn(II) polymer metal complexes are square planar and tetrahedral, respectively. All compounds were screened for their antimicrobial activities against Escherichia coli, Bacillus subtillis, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Candida albicans, Agelastes niger, and Microsporum canis using the Agar well diffusion method with 100 µg mL−1 of each compound.

Synthesis, characterization, electrical conductivity, and catalytic studies of some coordination polymers of salen-type schiff base

Coordination polymers of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) with the salen-type Schiff base 4,4′-bis[(N-ethanesalicylaldehydediamine-5)azo]biphenyl have been prepared and characterized by elemental analyses, IR and electronic spectra, magnetic susceptibility measurements, and thermogravimetric analysis. Thermogravimetric analysis confirms the coordination of H2O in complexes. The 1H NMR spectrum of ligand clearly indicates the presence of OH and azomethine groups. The octahedral geometry have been suggested for Mn(II), Fe(II), Co(II), and Ni(II) complexes, and square planar Cu((II), whereas tetrahedral is suggested for Zn(II) and Cd(II) polychelates. Thermal data have been analyzed for kinetic parameters by both Coat-Redfern and Broido methods. Solid-state dc conductivity of ligand and its polychelates was measured in their compressed pellet form over 313–413 K temperature range. Solidstate conductivity lies in the range 4.361 × 10−11 to 7.241 × 10−10 Ohm−1 cm−1 indicating their semiconducting behavior. Oxidation of styrene with selected catalysts was tested using H2O2 as an oxidant.

Coordination polymers of Mn(II) and Cu(II) orotate with 2-methylimidazole and N, N, N′, N′-tetramethylethylenediamine ligands: Syntheses, spectroscopic and thermal analyses and crystal structures of mer-[Mn(μ-HOr)(H 2O)(2-meim) 2] n and thermochromic {[Cu(μ-HOr)(tmen)] · 1.5H 2O} n complexes

The syntheses, FT-IR and UV–Vis spectra, thermal analyses and crystal structures of Mn(II) and Cu(II) orotate coordination polymers with 2-methylimidazole (2-meim) and N,N,N′ ,N′-tetramethylethylenediamine (tmen) ligands are described. The orotate ligand acts as a bridging ligand with two different coordination modes, the { mer-[Mn(μ-HOr)(H 2O)(2-meim) 2]} n ( 1) complex displays an linear chain structure in which each Mn(II) ion exhibits a distorted octahedral coordination by a tridentate orotate, two 2-meim and one aqua ligand. In {[Cu(μ-HOr)(tmen)] · 1.5H 2O} n ( 2), the Cu(II) ion is coordinated by a tridentate orotate and one bidentate tmen ligand, and exhibits a square pyramidal geometry. These polymer chains are linked by hydrogen-bond interactions forming a three-dimensional network. Complex 2 exhibits an irreversible thermochromic effect. After dehydration, the color of the complex changes from blue to green.

1D slide-fastener-like coordination polymers of Mn(II) derived from pyrazine-2,3,5,6-tetracarboxylic acid

Two new 1D slide-fastener-like coordination polymers {[Mn 2(pztc)(phen) 2(H 2O) 2]·4H 2O} n ( 1) and {[Mn 2(pztc)(bpy) 2(H 2O) 2]·2H 2O} n ( 2) have been synthesized by the reactions of pyrazine-2,3,5,6-tetracarboxylic acid (pztcH 4) and Mn(OAc) 2·4H 2O in the presence of 1,10-phenanthroline (phen) or 2,2′-bipyridine (bpy) under hydrothermal conditions and characterized by elemental analyses, FT-IR, TGA and X-ray diffraction. In complex 1 and 2, metal ions are bridged by pyrazine-2,3,5,6-tetracarboxylate, coordinating in a hexadentate manner, so forming 1D polymeric chains. The remaining coordination sites of the metal ions are occupied by one O atom of water molecule and two N atoms of the terminal ligand (phen or bpy). IR spectra and thermal analysis data are in agreement with the crystal structure.

In vitro antibacterial and antifungal assay of poly‐(ethylene oxamide‐N,N′‐diacetate) and its polymer–metal complexes

AbstractA new polyester, poly‐(ethylene oxamide‐N,N′‐diacetate) (PEODA), containing glycine moiety was synthesized by the reaction of oxamide‐N,N′‐diacetic acid and ethylene glycol and its polymer–metal complexes were synthesized with transition metal ions. The monomer oxamide‐N,N′‐diacetic acid was prepared by the reaction of glycine and diethyl oxalate. The polymer and its metal complexes were characterized by elemental analysis and other spectroscopic techniques. The in vitro antibacterial activities of all the synthesized polymers were investigated against some bacteria and fungi. The analytical data revealed that the coordination polymers of Mn(II), Co(II) and Ni(II) are coordinated with two water molecules, which are further supported by FTIR spectra and TGA data. The polymer–metal complexes showed excellent antibacterial activities against both types of microorganisms; the polymeric ligand was also found to be effective but less so than the polymer–metal complexes. On the basis of the antimicrobial behavior, these polymers may be used as antifungal and antifouling coating materials in fields like life‐saving medical devices and the bottoms of ships. Copyright © 2007 John Wiley & Sons, Ltd.

Transition metal(II) ions with dinegative tetradentate schiff base

Some new coordination polymers of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), obtained from the interaction of metal acetate with dipotassium salt of N,N’-di(carboxyethylidene)terephthalaldehydediimine (K2SB) are described. The products, which have been characterized by elemental analyses, magnetic measurements, thermogravimetric analyses, electronic and infrared spectral studies, have composition, [M(SB)(H2O)2]n. These colored coordination polymers are non-hygroscopic and quite stable at room temperature. On the basis of analytical data and IR studies, a 1:1 metal to ligand stoichiometry has been suggested to these coordination polymers. The IR studies have also revealed that ligands are coordinated to metal ion through carboxy oxygen and azomethine nitrogen. All the studies suggested tetradentate nature of the ligand with octahedral symmetry of the coordination polymers. All the coordination polymers are insoluble in acetone, ethanol, chloroform, methanol, benzene, DMF and DMSO. The thermal decomposition of the coordination polymers is studied and indicates that not only the coordinated water is lost but also that the decomposition of the ligand from the coordination polymers is necessary to interpret the successive mass loss.

Synthesis and Characterization of Coordination Polymers of 1,2‐bis‐(4‐Thio‐1,3,5‐hexahydro‐1‐triazinyl)ethane

Coordination polymers of Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) with the 1,2‐bis‐(4‐thio‐1,3,5‐hexahydro‐1‐triazinyl)ethane (H2BTHTE) ligand have been prepared in DMF solution. The coordination polymers have been characterized by their elemental analyses, magnetic susceptibility and by electronic and infrared spectral measurements. The thermal stability of each polymer was determined by thermogravimetric analysis. The thermal stability of the coordination polymers obtained from the thermograms is in the following order: Fe > Zn > Mn = Co > Ni > Cu. The Cu(II), Co(II), Ni(II) and Fe(II) coordination polymers are of six‐coordinated octahedral geometry while the Mn(II) and Zn(II) coordination polymers are of four‐coordinated tetrahedral structure. The ligand field and nephelauxetic parameters have been determined from the spectra using the ligand field theory of spin‐allowed transitions and which were found to be consistent with six‐coordinated structures for the Cu(II), Co(II), Ni(II) and Fe(II) coordination polymers. Elemental analyses indicate a ligand metal ratio of 1:1 in all of the coordination polymers and the coordination of water molecules with the central metal atom in the case of the Cu(II), Fe(II), Co(II) and Ni(II) coordination polymers.

Syntheses and Study of Some New Coordination Polymers Mn (II) with Semiconductor Properties

In this paper, the synthesis and the study of some coordination polymers of Mn (II) with ligands derived from acids: dinaphtylphosphinic, dinaphtylthiophosphinic and dinaphtyldithiophosphinic are presented. The synthesis was accomplished by refluxing in organic solvents the reactants: acetylacetonate of Mn (II) and one of the respective phosphinic acids. Studies were performed applying the following methods: chemical analysis, gel chromatography: IR-spectroscopy; ESR, X-ray diffraction, thermogravimetric analysis and electrical resistance measurements in the field of temperature 20–200°C. All the studied compounds present semiconductor properties, having the resistivity of 10−8 ohm·cm−1. The activation energy is approximately 0.9 eV; they also present a good thermal stability resisting to the heat effect till at least 300°C.The semiconductor properties are depending on the nature of the ligands. These results are comparable to the semiconductor properties of other coordination polymers of transitional metals.Based on experimental data and literature indications, the structural formulae of these compounds are assigned.

Coordination polymers of Mn(II) with the ligand pyrazine-2,3,5,6-tetracarboxylic acid

Two coordination polymers of Mn(II) with the ligand pyrazine-2,3,5,o-tetracarboxylic acid (H 4pztc) have been prepared. The reaction of MnSO 4 with H 4pztc (ratio 1:1) carried out at 50 °C gave a zig-zag polymer structure with the ligand coordinated in a pseudo bis(tridentate) fashion ( 1) (crystal data: C 8H 10N 2O 12Mn, tetragonal, space group I4 1/ a, a = b = 13.934(1), c = 13.578(1) Å, Z = 8, 1670 reflections with I>3σ( I), R = 0.029). The reaction of an excess of MnSO 4 with H 4pztc (ratio 3:1) at room temperature gave the salt [Mn(H 2O) 6][H 2pztc] ( 2) (crystal data: C 8H 14N 2O 14Mn, monoclinic, space group A2/ n, a = 6.83(1), b = 9.918(1), c = 22.051(2) Å, β = 102.91(2)°, Z = 4, 1547 reflections with I>3σ( I), R = 0.026). The anion possesses a strong intramolecular H bond and is found coordinated to the Mn atom in polymer 1. The reaction of MnSO 4 with H 4pztc (ratio 1:1) carried out at 50 °C in the presence of the equimolar buffer CH 3COOK/CH 3COOH, gave a column type polymer with the ligand coordinated in a mono(tridentate)-bis(monodentate) fashion ( 3) (crystal data: C 8H 7N 2O 11.25K 2Mn, monoclinic, space group I2/ a, a = 18.207(2), b = 8.335(1), c = 19.185(3) Å, β = 103.66(1)°, Z = 8, 1539 reflections with I>2σ( I), R = 0.041). The reaction of H 4pztc with ZnCl 2 (ratio 1:1) in the presence of the same equimolar buffer solution lead to the formation of the isomorphous polymer Zn- 3 (crystal data: C 8H 7N 2O 11.25K 2Zn, monoclinic, space group I2/ a, a = 18.194(1), b = 8.264(1), c = 18.924(1) Å, β = 103.92(1)°, Z = 8, 2567 reflections with I>3σ( I), R = 0.031).

Magnetic, Spectral, Thermal, and Electrical Properties of Coordination Polymers Derived From ß,ß'-(2-Hydroxyl-5-Methylbenzoyl)-p-Divinylbenzene

Abstract Coordination polymers of Mn(II), Fe(II), Co(II), Ni(II), Cu(II), and Zn(II) have been prepared from β,β'-(2-hydroxyl-5-methylbenzoyl)-p-divinylbenzene. The analytical data are found to be consistent with 1:1 metal:ligand stoichiometry. Elemental analyses, magnetic, spectral (IR and electronic), thermal, and electrical properties of the coordination polymers have been studied, and probable structures are assigned to them. All of them are amorphous powders and insoluble in common organic solvents.

Effects of gamma rays on the electrical conductivity of polychelates

Values of the electrical conductivities (δ) of the coordination polymers of Mn, Co, Ni, Cu, Zn and Cd with the poly (Schiff base) ligand (PSB), derived from 4,4′-diaminodiphenyl methane and 5,5′-methylene bis-salicylaldehyde, were measured over the temperature range of 300–550 K. A slight variation in δ was found, the values decreasing in the order δ Ni > δ Co > δ Cu > δ Zn > δ Mn > δ Cd > δ PSB. The effect of γ-irradiation on the electrical conductivities of PSB and its polychelates was also studied. The radiation-induced electrical conductivities of the compounds investigated were found to decrease with increasing radiation dose. The conductivity data and the Seebeck voltage values showed that γ-irradiated and unirradiated complexes behave as n-type semi-conductors. The effects of γ-irradiation on the electrical conductivity, activation energies for electrical charge transfer, charge carriers and the conduction mechanism in PSB and its polychelates are discussed.