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This paper describes the synthesis and structural characterization of two new one-dimensional coordination polymers involving 1,3-bis(4-pyridyl)propane ligand named {(μ-NCS)2[Cu(bpp)] ·dmf} n ( 1) and {[Cu(mebpy)(bpp)(dmso)](ClO4)2 ·dmso} n ( 2) (bpp = 1,3-bis(4-pyridyl)propane and mebpy = 4,4'-dimethyl-2,2'-bipyridine). These compounds were characterized by means of elemental analysis, thermal analysis (TG/DTA), vibrational spectroscopy (IR and Raman) and had their structures determined by single-crystal X-ray diffraction analysis. Compound 1 consists of CuN4 coordination spheres with bpp ligands in the unusual GG conformation coordinated in bridges between CuII centers to form a wavelike 1-D coordination polymer. On the other hand, in compound 2 the bpp ligand adopts the TT conformation in bridging mode extending the 1D cationic polymeric chain. [ABSTRACT FROM AUTHOR]

A mixed‐valent, one‐dimensional Cu(I/II) coordination polymer with the formula [CuII{CuI3(Hmpba)(mpba)2}DMF] ⋅ ∼3DMF was obtained with the bifunctional ligand 4‐(3,5‐dimethyl‐1H‐pyrazol‐4‐yl)benzoic acid (H2mpba) in N,N‐dimethylformamide (DMF) via solvothermal reaction. The compound exhibits a trinuclear {CuI3(Hmpba)(mpba)2}2− metallo‐linker with the softer Cu(I) linearly‐coordinated by the softer pyrazolate nitrogen donor atom. This metallo‐linker connects the harder Cu(II) ions through its harder carboxylate groups into a chain structure. Two Cu(II) ions form a paddlewheel unit and are, thus, surrounded by four carboxylate groups. Cu(II) is five‐coordinated with a terminal DMF ligand. Parallel chains are connected into supramolecular layers through the common R22(8) hydrogen‐bond motif of the singly‐deprotonated carboxyl groups of the Hmpba ligand. These layers are further organized by Cu(I)−Cu(I) interactions into a 3D supramolecular array. [ABSTRACT FROM AUTHOR]

Two Cu coordination polymers [Cu(bpmt)Cl2·2DMF]n (1), [Cu(bpmt)(μ‐Cl)·DMSO]n (2) [bpmt = N1,N4‐bis(pyridin‐2‐ylmethyl)terephthalamide)], were synthesized and characterized. X‐ray single‐crystal diffractions revealed complex 1 exhibits a one‐dimensional (1D) chain in which central CuII ions are located in a six‐coordinate slightly distorted octahedral structure. Complex 2 features 1D chain composed of CuI–Cl bridges and all the central CuI ions are situated a twisted tetrahedral configurations. Multi‐spectroscopic DNA interaction studies indicate that the two complexes may bind to DNA via groove binding modes, and the calculated binding constants are 1.42 × 104 (1‐CT‐DNA) and 1.41 × 104 (2‐CT‐DNA). Both complexes are also capable of efficiently cleaving plasmid pBR322 DNA in the presence of H2O2 via an oxidative mechanism. Furthermore, 1 and 2 are employed as catalysts for the oxidation of 1‐phenylethanol to acetophenone. Complex 1 displays good catalytic potential with the conversion rate reaches 99 % using tert‐butyl hydroperoxide (TBHP) as oxidant and CH3CN as solvent at 60 °C for 2.0 h. [ABSTRACT FROM AUTHOR]

Complex [Cu(tbt)Cl2]n (tbt = 1‐tert‐butyl‐1H‐tetrazole) was prepared by reaction of tbt with copper(II) chloride in solution. According to single‐crystal X‐ray analysis, this complex presents 1D coordination polymer, formed at the expense of double chlorido bridges between neighboring pentacoordinate copper(II) cations. 1‐tert‐Butyl‐1H‐tetrazole acts as monodentate ligand coordinated by CuII cations via the heteroring N4 atoms. The temperature‐dependent magnetic susceptibility measurements of novel complex [Cu(tbt)Cl2]n as well as described previously 1D coordination polymer [Cu(tbt)2Cl2]n, and linear trinuclear complex [Cu3(tbt)6Br6], were carried out. Magnetic studies revealed that the copper(II) ions were weakly ferromagnetically coupled in polymeric copper(II) chloride complexes, whereas complex [Cu3(tbt)6Br6] showed antiferromagnetic coupling. [ABSTRACT FROM AUTHOR]

A newly synthesized coordination polymer, [(CH3)3NH]2[CuZn(CN)5], was investigated using 13C and 63Cu solid‐state NMR techniques and single‐crystal X‐ray diffractometry. It consists of a three‐dimensional (3D) net composed of tetrahedral CuI and ZnII ions and CN– ligands bridging between the two metal ions. (CH3)3NH+ ions are trapped in the inner space of the 3D net. Three coordination sites of each metal ion are used for the formation of the 3D net and the remaining site is occupied by a unidentate CN– ligand. The structure of the 3D net is chiral and categorized as srs in the notation of the Reticular Chemistry Structure Resource (RCSR). In water vapor or open air at room temperature under ambient pressure, a powder of [(CH3)3NH]2[CuZn(CN)5] showed a structural transformation to [(CH3)3NH][CuZn(CN)4]·1.5H2O, which is a known compound with a diamond‐like 3D net of [CuZn(CN)4]– composed of tetrahedral CuI and ZnII ions and bridging CN– ligands. 63Cu solid‐state NMR spectroscopy revealed that the Cu‐CN‐Zn orientation of the bridging CN– ligands was conserved after the structural transformation. [ABSTRACT FROM AUTHOR]

Blue single crystals of Cu[μ3-O3P(CH2)2COOH]·2H2O (1) and Cu[(RS)-μ3-O3PCH(C2H5)COOH]·3H2O (2) were prepared in aqueous solutions (pH = 2.5-3.5). 1 crystallizes in space group Pbca (no. 61) with a = 812.5(2), b = 919.00(9), and c = 2102.3(2) pm. Cu2+ is fivefold coordinated by three oxygen atoms stemming from [O3P(CH2)2COOH]2- anions and two water molecules. The Cu-O bond lengths range from 194.0(3) to 231.8(4) pm. The connection between the [O3P(CH2)2COOH]2- anions and the Cu2+ cations yields a polymeric structure with layers parallel to (001). The layers are linked by hydrogen bonds. 2 crystallizes in space group Pbca (no. 61) with a = 1007.17(14), b = 961.2(3), c = 2180.9(4) pm. The copper cations are surrounded by five oxygen atoms in a square pyramidal fashion with Cu-O bonds between 193.6(4) and 236.9(4) pm. The coordination between [O3PCH(C2H5)COOH]2- and Cu2+ results in infinite puckered layers parallel to (001). The layers are not connected by any hydrogen bonds. Each layer contains both R and S isomers of the [O3PCH(C2H5)COOH]2- dianion. Water molecules not bound to Cu2+ are intercalated between the layers. UV/Vis spectra suggest three d-d transition bands at 743, 892, 1016 nm for 1 and four bands at 741, 838, 957, and 1151 nm for 2, respectively. Magnetic measurements suggest a weak antiferromagnetic coupling between Cu2+ due to a super-superexchange interaction. Thermoanalytical investigations in air show that the compounds are stable up to 95 °C (1) and 65 °C (2), respectively. [ABSTRACT FROM AUTHOR]

1-tert-Butyl-1H-1,2,4-triazole (tbtr) was found to react with copper(II) chloride or bromide to give the complexes [Cu(tbtr)2X2]n and [Cu(tbtr)4X2] (X = Cl, Br). 1-tert-Butyl-1H-tetrazole (tbtt) reacts with copper(II) bromide resulting in the formation of the complex [Cu3(tbtt)6Br6]. The obtained crystalline complexes as well as free ligand tbtr were characterized by elemental analysis, IR spectroscopy, thermal and X-ray analyses. For free ligand tbtr, ¹H NMR and 13C NMR spectra were also recorded. In all the complexes, tbtr and tbtt act as monodentate ligands coordinated by CuII cations via the heteroring N4 atoms. The triazole complexes [Cu(tbtr)2Cl2]n and [Cu(tbtr)2Br2]n are isotypic, being 1D coordination polymers, formed at the expense of single halide bridges between neighboring copper(II) cations. The isotypic complexes [Cu(tbtr)4Cl2] and [Cu(tbtr)4Br2] reveal mononuclear centrosymmetric structure, with octahedral coordination of CuII cations. The tetrazole compound [Cu3(tbtt)6Br6] is a linear trinuclear complex, in which neighboring copper(II) cations are linked by single bromide bridges. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) 3d-4f complex, [Cu(en)2][Sm2(C5O5)(C2O4)3(H2O)2] ·8H2O ( 1) (en = ethylenediamine, C5O52- = dianion of 4,5-dihydroxycyclopent-4-ene-1,2,3-trione), were prepared via the in-situ ring-opening oxidation reaction of croconate in the presence of the template-directed complex, [Cu(en)2]2+ cation. The structural characterization determined by X-ray diffraction determination reveals that the 3D anionic coordination polymer of [Sm2(C2O4)3(C5O5)(H2O)2]2- in 1 can be describe in terms of in-plane 2D honeycomb-like [Sm2(C2O4)3] layered frameworks bridged by oxalate with bis-chelating mode, being mutually interlinked via the bridge of μ1,2,3,4-croconate ligands with bis-chelating coordination mode to complete the 3D open framework, which gives rise to 1D channels with pore size of 14.023 × 11.893 Å (longest atom-atom contact distances) along the b axis. The structure-directing complex, [Cu(en)2]2+, and solvated water molecules are resided into these honeycomb-type hexagonal channels. The thermal stability of 1 was further studied by TGA and in-situ powder X-ray diffraction measurement. [ABSTRACT FROM AUTHOR]

Abstract. Two bis-triazole-bis-amide-based copper(II) pyridine-2,3-dicarboxylate coordination polymers (CPs), [Cu(2,3-pydc)(dtb)0.5(DMF)] ·2H2O ( 1) and [Cu(2,3-pydc)(dth)0.5(DMF)] ·2H2O ( 2) (2,3-H2pydc = pyridine-2,3-dicarboxylic acid, dtb = N, N′-bis(4 H-1,2,4-triazole)butanamide, and dth = N, N′-bis(4 H-1,2,4-triazole)hexanamide), were synthesized under solvothermal conditions. CPs 1 and 2 show similar two-dimensional (2D) structures. In 1, the 2,3-pydc anions bridge the CuII ions into a one-dimensional (1D) chain. Such 1D chains are linked by the dtb ligands to form a 2D layer. The adjacent 2D layers are extended into a three-dimensional (3D) supramolecular architecture by hydrogen-bonding interactions. The electrochemical properties of 1 and 2 were investigated. [ABSTRACT FROM AUTHOR]

The 2D coordination polymer {[Cu32(pa)24(µ2-OH)8(µ3-OH)8(bibp)8]·(CH3OH)3(H2O)5}∞ was prepared by the solvothermal reaction of Cu(NO3)2·3H2O with phthalic acid (H2pa) and 4,4'-bis-(imidazol-1-yl)biphenyl (bibp). The CuII ions show five different kinds of coordination environments, which are all connected by the pa2- ion into an interesting 1D carboxylate-copper chain with rare icosacopper and tetracopper clusters. The 1D chain is further bridged by the bibp ligand to form a 2D layer, which could be viewed as an unprecedented (4,4) lattice based on rectangular and butterfly-shaped tetracopper clusters with the ratio of 2:6. The magnetic properties were studied, and the results show antiferromagnetic interaction in the complicated 1D chain. [ABSTRACT FROM AUTHOR]

Three coordination polymers, namely {[Cu(5-nipa) (L22)](H2O)2}n (1), [Zn(5-nipa)(L22)(H2O)]n (2), and {[Cd2(5-nipa) 2(L22)(H2O)3](H2O)3.6}n (3), were prepared under similar synthetic method based on 1,2-(2-pyridyl)-1,2,4-triazole (L22) and ancillary ligand 5-nitro-isophthalic acid (5-H2nipa) with CuII, ZnII, and CdII perchlorate, respectively. All the complexes were characterized by IR spectroscopy, elemental analysis, and powder X-ray diffraction (PXRD) patterns. Single-crystal X-ray diffraction indicates that complexes 1 and 2 show similar 1D chain structures, whereas complex 3 exhibits the 2D coordination network with hcb topology. The central metal atoms show distinct coordination arrangements ranging from distorted square-pyramid for CuII in 1, octahedron for ZnII in 2, to pentagonal- bipyramid for CdII in 3. The L22 ligand adopts the same (η3,μ2) coordination fashion in complexes 1-3, while the carboxyl groups of co-ligand 5-nipa2- adopt monodentate fashion in 1 and 2 and bidentate chelating mode in 3. These results indicate that the choice of metal ions exerts a significant influence on governing the target complexes. Furthermore, thermal stabilities of complexes 1-3 and photoluminescent properties of 2 and 3 were also studied in the solid state. [ABSTRACT FROM AUTHOR]

The coordination polymers, {[Cu(Hbidc)(2, 2′-bpy)(H2O)] ·2H2O} n ( 1) and {[Mn(Hbidc)(2, 2′-bpy) (H2O)2] ·2H2O} n ( 2) (H3bidc = benzimidazole-5, 6-dicarboxylic acid, 2, 2′-bpy = 2, 2′-bipyridine), were synthesized in solution and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TGA), and single-crystal X-ray diffraction. Complexes 1 and 2 consist of different 1D chain structures. In both compounds, 2, 2′-bpy is chelating in a bidentate manner, whereas the Hbidc ligands in complexes 1 and 2 display chelating-bridging tridentate and bridging bidentate coordination modes. The two complexes are further extended into 3D supramolecular structures through O-H ···O and N-H ···O hydrogen bonds. The thermal stabilities of complexes 1 and 2 were studied by thermogravimetric analyses (TGA). [ABSTRACT FROM AUTHOR]

Hydrothermal reaction of the requisite metal nitrate, carboxycinnamic acid (H2cca), and the long-spanning dipyridylamide bis(4-pyridylformyl)piperazine (4-bpfp) generate crystalline coordination polymers whose topology depends critically on the metal coordination geometric preference. These two new phases were structurally characterized by single-crystal X-ray diffraction. {[Cu(cca)(4-bpfp)] ·2.5H2O} n ( 1) manifests a non-interpenetrated 6-connected pcu net based on chain motifs featuring carboxylate-bridged {Cu2(OCO)2} dinuclear units, with embedded D(5) water molecule chains. {[Ni(cca)(4-bpfp)(H2O)2] ·3H2O} n ( 2) displays an acentric twofold interpenetrated 4-connected 66 dia network topology with entrapped R(4)A(1) water molecule rings. Variable temperature magnetic studies performed on 1 revealed very weak antiferromagnetic coupling within its dinuclear units. Thermal properties of these two new materials are also discussed. [ABSTRACT FROM AUTHOR]

Slow diffusion reaction of 2,2′-dithiodibenzoic acid (dtdb) with CuCl2 in the presence of N-donor ligands results in the formation of different coordination polymers where both S-S and C-S scission and oxidation of S is observed. X-ray diffraction analysis of [Cu(tdb)(phen)(H2O)]2 ·2H2O.2DMF] ( 1), [Cu(tdb)(py)2(H2O)]2 ( 3), and [Cu(tdb)(bipy)(H2O)]2 ·0.5H2O ( 4) (tdb = thiodibenzoic acid, phen = phenanthroline, py = pyridine, bipy = 2,2′-bipyridine) show that the metal ions are coordinated to the carboxylate oxygen atoms of the in situ generated tdb ligand in a monodenate fashion. In [Cu(phen)(SO4)2(H2O)2] n ( 2) and [Cu(bipy)(SO4)2(H2O)2] n ( 5), the sulfur is oxidized to sulfate ions prior to coordination with the metal. Complex 1 has a dimeric structure with π-π interactions between the phen ligands, whereas 3 and 4 form 1D polymeric chains. [ABSTRACT FROM AUTHOR]

A CuII complex with azide and a bifunctional ligand bearing carboxylate and isoxazolate groups, namely [Cu(L)(N3)] n ( 1) (L = 4-isoxazole carboxylate, was synthesized by diffusion methods and characterized by X-ray crystallography. In compound 1, the CuII chains with alternating double (μ-azide)(μ-carboxylate) and the unprecedented triple (μ-azide)(μ-carboxylate)(μ-isoxazolate) bridges are interlinked by the organic spacers into a two-dimensional framework. Magnetic studies demonstrated that ferromagnetic interactions exist between the neighboring CuII ions through the alternating mixed double and triple bridges. [ABSTRACT FROM AUTHOR]