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2. Copper(II) Coordination Polymers Generated from 1,3-Bis(4-pyridyl)propane: Synthesis, Structures, and Spectroscopic Studies.
- Author
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Farani, Regis A., Da Fonseca, Daniella M. F., De Paula, Elgte Elmin B., Bortoluzzi, Adailton J., Hörner, Manfredo, Diniz, Renata, and Machado, Flávia C.
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COORDINATION polymers ,COORDINATION number (Chemistry) ,BIPYRIDINE ,INFRARED spectroscopy ,RAMAN spectroscopy - Abstract
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]- Published
- 2014
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3. Synthesis and Characterization of HgII/Se/CuI Multinuclear Compounds from Mercury(II) Bis(p‐aminobenzeneselenolate) – Hg(SeC6H4NH2‐p)2.
- Author
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Bublitz, Fabricio, de Azevedo Mello, Melina, Cocco Durigon, Daniele, Dornelles da Silva, Felipe, Hennemann, Artur Luis, and Schulz Lang, Ernesto
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- *
MERCURY , *MERCURY compounds - Abstract
In this paper we explore an amino functionalized selenolate unit for the synthesis of new multinuclear compounds with promising interesting properties and potential precursors of semiconductors. We present for the first time the X‐ray crystallographic structure of [Hg(SeC6H4NH2)2]2·diox (1·diox) and its copper(I) derivatives: HgCu2X2(SeC6H4NH2)2(PPh3)4·4diox [X = Br (2·4diox) and I (3·4diox)]. The compounds 1 and 2, 3 can be considered as the starting material and intermediates, respectively, for the synthesis of ternary HgII/Se/CuI nanoclusters. We also provide IR and NMR spectroscopic data and evaluate the optical features of these compounds by difuse reflectance UV/Vis spectroscopy. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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4. Synthesis and Characterization of Luminescent Binuclear μ‐HS Cu(I) Complexes.
- Author
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Li, Ting‐Ting, Kuang, Xiaofei, Wang, Ming‐Ming, Yang, Hui, Mi, Ying‐Hao, and Lu, Can‐Zhong
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COPPER ,PHTHALAZINE ,DIPHENYLPHOSPHINE ,TRANSITION metal complexes - Abstract
Photoactive Cu(I) complexes are promising luminescent materials owing to their abundant reserves and marvelous biocompatibility. In this work, we report the synthesis and characterization of two binuclear sulfur‐bridged Cu(I) complexes (POP)2Cu2(μ‐HS/Cl)2 ⋅ 0.92MeOH 1 (POP=(oxybis(2,1‐phenylene))bis(diphenylphosphine)) and (POP)2Cu2(μ‐HS)22, which were prepared by one‐pot facile solvothermal method with copper‐4‐tert‐butylbenzenethiol (CuSC6H4tBu) and POP as precursors. Complex 1 exhibits sky‐blue emission while complex 2 displays blue. Complex 1 was systemically investigated by PXRD, UV‐vis spectrum, IR, TGA and steady‐state spectra. Temperature‐dependent steady‐state emission and decay lifetime indicate that complex 1 is a typical phosphorescent emitter. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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5. 5‐Amino‐2‐isopropenyltetrazole and its Cupric Chloride Complex: Synthesis, Structure and Magnetism.
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Voitekhovich, Sergei V., Lyakhov, Alexander S., Ivashkevich, Ludmila S., Matulis, Vadim E., Grigoriev, Yuri V., Klose, Jennifer, Kersting, Berthold, and Ivashkevich, Oleg A.
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CUPRIC chloride ,NATURAL orbitals ,MAGNETISM ,TETRAZOLES ,SINGLE crystals ,COPPER chlorides - Abstract
A new tetrazole ligand, 5‐amino‐2‐isopropenyltetrazole, was prepared by regioselective alkylation of 5‐aminotetrazole with allyl bromide in sulfuric acid followed by dehydrobromination of intermediate 5‐amino‐2‐(1‐bromopropan‐2‐yl)tetrazole. 5‐Amino‐2‐isopropenyltetrazole (L) was found to react with copper(II) chloride to generate complex [CuL2Cl2]n. The ligand and its complex were characterized by single crystal X‐ray and thermal analyses. Complex [CuL2Cl2]n presents 1D coordination polymer, formed at the expense of double chlorido bridges between neighbouring octahedral coordinated CuII cations. Tetrazole ligand acts as monodentate ligand coordinated by CuII cations via the heteroring N4 atoms only. Magnetic studies revealed that the copper(II) ions were weakly antiferromagnetically coupled. Natural bond orbital analysis was performed to explain the structural peculiarities of the ligand. Its basicity and the relative stability of the protonated forms were investigated using MO calculations. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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6. Keeping dysprosium in line: Trinuclear heterometallic MII2DyIII complexes with M=Cd, Co and Cu.
- Author
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Ruppert, Thomas, Schlittenhardt, Sören, Suryadevara, Nithin, Fuhr, Olaf, Anson, Christopher E., Ruben, Mario, and Powell, Annie K.
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DYSPROSIUM ,MAGNETIC susceptibility ,MAGNETIC measurements ,SINGLE crystals ,COPPER ,CRYSTAL structure - Abstract
Four new heterometallic trinuclear essentially linear ("in‐line") MII2DyIII complexes (M=CdII (1), CoII (2), CuII (3, 4) were synthesised using the ligand 3,5‐di‐tert‐butylbenzoic acid (dtbbaH) in a MeCN : iPrOH (1–3) or in a MeOH : iPrOH : DMF (4) mixture. Single crystal structure analyses revealed the formation of [Cd2Dy(dtbba)6(iPrOH)2(H2O)2NO3] ⋅ iPrOH (1), [Co2Dy(dtbba)6(iPrOH)2(H2O)2NO3] ⋅ iPrOH (2), [Cu2Dy(dtbba)6(MeCN)4NO3] ⋅ MeCN (3) and [Cu2Dy(dtbba)6(iPrOH)1.68(DMF)1.32(H2O)NO3] ⋅ 3iPrOH ⋅ H2O (4). The M−Dy−M angles become more acute from (1) to (3) leading to decreased M⋅⋅M distances. The DyIII ions are 8‐coordinate with a distorted triangular dodecahedron geometry and a D2d symmetry whereas the geometry of the 5‐coordinate terminal MII ions can best be described as either distorted vacant octahedra or as spherical square pyramids with a C4v symmetry. Magnetic susceptibility measurements were performed on (1), (2) and (3) which allows a comparison of the effect of replacing highly anisotropic CoII with the quantum spin of CuII. Both (2) and (3) show effects of ferromagnetic interactions at low temperatures. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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7. Syntheses, Structures and Cytotoxicity of Cu(II) Complexes with α‐Amino acid derived Benzamidines.
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Dinh Le, Canh, Thang Pham, Chien, and Huy Nguyen, Hung
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METHYL formate ,METHYL chloride ,ACIDS ,GLYCINE ,CANCER cells ,CARBOXYLATES - Abstract
N‐(diethylthiocarbamoyl)benzimidoyl chloride reacts with methyl esters of glycine, L‐alanine, L‐valine under formation of pro‐ligands 1 which undergo de‐esterification in reactions with Cu(CH3COO)2 and finally form complexes 2 with the compositions of [{Cu(L‐gly)}4] (2 a), [{Cu(L‐ala)}∞] (2 b) and [{Cu(L‐val)}∞] (2 c). In all complexes, Cu(II) ion is coordinated by a dianion {L2−} via its (O,N,S) donor set and a bridging carboxylate O atom, and thus, adopts a distorted square‐planar coordination sphere. Treatment of complexes 2 with equimolar amounts of o‐phenanthroline results in the formation of square pyramidal ternary complexes with the compositions of [Cu(L)phen] (L=L‐gly, L‐ala, L‐val) (3). Antiproliferative effects of the compounds on MCF‐7 and Hep‐G2 cancer cells were studied. Generally, the ternary complexes 3 are more active than the complexes 2 and the pro‐ligands 1. In each series of compounds, the derivatives of L‐valine show higher cytotoxicity than those of L‐alanine and glycine. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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8. Direct Synthesis and Characterization of Copper(II) 1‐Phenyltetrazol‐5‐olates.
- Author
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Voitekhovich, Sergei V., Lyakhov, Alexander S., Ivashkevich, Ludmila S., Lavrov, Alexander N., Lavrenova, Ludmila G., and Ivashkevich, Oleg A.
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COPPER ,TETRAZOLES ,COPPER ions ,SINGLE molecule magnets ,ETHYLENEDIAMINE ,METALS - Abstract
The interaction of 1‐phenyl‐1,4‐dihydro‐5H‐tetrazol‐5‐one (Hpto) with ethylenediamine (en) and metallic copper in ethanol in the open air was found to yield molecular complexes [Cu(en)2(pto)2] (1) or [Cu2(en)2(EtOH)2(pto)4] (2) depending on the reagents ratio. Deprotonated tetrazol‐5‐one, i.e 1‐phenyltetrazol‐5‐olate anion (pto) acts as a monodentate ligand coordinated to the metal via the tetrazole ring N4 atom in mononuclear complex 1, and as a bridging ligand coordinated via the tetrazole ring N4 and N3 atoms in binuclear complex 2. The latter was found to be a paramagnet, with a very weak antiferromagnetic exchange interaction between copper ions. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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9. A mixed‐valence copper(I/II) coordination polymer directed with a bifunctional soft‐hard pyrazolate−carboxylate ligand.
- Author
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Menzel, Saskia, Höfert, Simon‐Patrick, Öztürk, Secil, Schmitz, Alexa, and Janiak, Christoph
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CARBOXYLATES ,COPPER ,BENZOIC acid ,CARBOXYL group ,COORDINATION polymers - Abstract
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]
- Published
- 2021
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10. Electrochemical Synthesis of Triphenylphosphine Coinage Metal Complexes stabilized by closo‐Dodecaborates [B12X12]2− (X=H, F, Cl, Br, I).
- Author
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Exner, Rüdiger M., Jenne, Carsten, and Wegener, Bianca
- Abstract
The synthesis of salts of reactive cations and weakly coordinating anions is of great interest to the development of catalysts, because the weak electrostatic interaction between the two may greatly increase catalytic activity and solubility in nonpolar solvents. However, the synthesis of these salts is in many cases difficult and requires elaborate, sometimes multi‐step procedures. Here, we describe the synthesis of a library of monocationic group 11 metal‐triphenylphosphine complexes of dodecaborates generated by means of electrochemistry. The complexes of the general formula [M(PPh3)y(CH3CN)z]2[B12X12] (M=Cu, Ag, Au; X=H, F, Cl, Br, I; y=2–4; z=0–2) were synthesized from the free acid of the respective dodecaborate and the elemental metal in acetonitrile in the presence of triphenylphosphine. The reactions were performed in an electrochemical cell under ambient conditions in polypropylene containers in all cases. A total of 13 different crystal structures in the [M(PPh3)y(CH3CN)z]2[B12X12] system were obtained. As a by‐product in some reactions single crystals of [(H3O)(OPPh3)3]2[B12X12] (X=Cl, Br, I) were found. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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11. Copper Coordination Polymers of N1,N4‐Bis(pyridin‐2‐ylmethyl)terephthalamide: Synthesis, Structures, DNA Binding and Cleavage, and Catalytic Activity for Oxidation of 1‐Phenylethanol.
- Author
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Hu, Zhou‐Ping, Yu, Wei‐Dong, Liu, Xia, Tang, Qing, Fang, Zi‐Wei, and Zhang, Shou‐Chun
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COORDINATION polymers ,CATALYTIC oxidation ,CATALYTIC activity ,DNA ,BINDING constant ,DNA synthesis ,PLASMIDS - Abstract
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]
- Published
- 2020
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12. Crystal and Molecular Structures of Mononuclear Coordinated Copper(I) Complexes with Thio‐triazole and Thio‐triazine based Schiff base Ligands.
- Author
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Bazyari, Pariya, Tabatabaee, Masoumeh, Nasirizadeh, Navid, Dušek, Michal, and Eigner, Václav
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MOLECULAR structure ,SCHIFF bases ,MOLECULAR crystals ,TRIAZINES ,LIGANDS (Chemistry) ,CRYSTAL structure ,TRIAZINE derivatives - Abstract
Reaction of 4‐amino‐5‐methyl‐1,2,4‐triazol‐3(2H)‐thione (AMTT) and 4‐amino‐6‐methyl‐3‐thio‐3,4‐dihydro‐1,2,4‐triazin‐5(2H)‐one (AMTTO) with 2‐hydroxybenzaldehyde led to the synthesis of corresponding Schiff base ligands [(Z)‐4‐((2‐hydroxybenzylidene)amino)‐3‐methyl‐1H‐1,2,4‐triazole‐5(4H)‐thione (L1) and (Z)‐4‐((2‐hydroxybenzylidene)amino)‐6‐methyl‐3‐thioxo‐3,4‐dihydro‐1,2,4‐triazin‐5(2H)‐one (L2)]. Treatment of synthesized Schiff base ligands with CuCl provided the complexes [Cu(L1)3Cl] (1) and [Cu(L2)2Cl] (2). Synthesized complexes were characterized by elemental analyses, IR spectroscopy and X‐ray diffraction studies. Complex 1 consists of a metal ion coordinated with one chloride ion and three Schiff base ligands via sulfur atoms in a distorted tetrahedral environment, whereas 2 consists of a metal ion coordinated with one chloride ion and two sulfur atoms from two different Schiff base ligands in a trigonal planar arrangement. Crystal data for 1 at –153 °C revealed an orthorhombic space group Fdd2, a = 34.8088(7), b = 33.8156(8), c = 11.6142(2) Å, Z = 16, R1 = 0.0357; for 2 at –178 °C the symmetry was triclinic, space group P1, a = 7.27520(10), b = 15.4620(2), c = 23.7985(4) Å, α = 72.1964(13), β = 86.5208(12), γ = 89.8597(11)°, Z = 4, R1 = 0.0359. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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13. Synthesis, Characterization, and Electrocatalytic Behavior for Hydrogen Evolution of a Dinuclear Copper(II) Complex of 1‐[(2‐Carboxymethyl) benzene]‐3‐[2‐carboxybenzene] triazene.
- Author
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Xie, Zhen‐Lang, Liu, Wei‐Xia, Wang, Nan‐Shu, and Zhan, Shu‐Zhong
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COPPER ,METAL-metal bonds ,BENZENE ,HYDROGEN evolution reactions ,HYDROGEN ,CATALYSTS ,BENZENE derivatives - Abstract
A dinuclear copper(II) complex, [CuII2(L)2] is afforded by the reaction of CuCl2·2H2O with a triazenido ligand, 1‐[(2‐carboxymethyl) benzene]‐3‐[2‐carboxybenzene] triazene (H2L). Structural investigation shows that the copper‐copper distance [2.3985(7) Å] is significantly shorter than the sum of the van der Waals radii of Cu (1.40 Å), suggesting that there are metal‐metal bonds in [CuII2(L)2]. In solid, there is a strong antiferromagnetic interaction between copper(II) ions (J = –135.6 cm–1). In homogeneous environment, [CuII2(L)2] shows electrocatalytic activities for hydrogen generation both from acetic acid with a turnover frequency (TOF) of 32 mol of hydrogen per mole of catalyst per hour [mol(H2)·mol–1(catalyst)·h–1] at an overpotential (OP) of 941.6 mV, and neutral buffer with a TOF of 512 mol(H2)·mol–1(catalyst)·h–1 at an OP of 836.7 mV. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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14. Halido‐bridged Copper(II) Complexes with 1‐tert‐Butyl‐1H‐tetrazole: Crystal Structure and Magnetic Properties.
- Author
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Voitekhovich, Sergei V., Degtyarik, Mikhail M., Lyakhov, Alexander S., Ivashkevich, Ludmila S., Klose, Jennifer, Kersting, Berthold, and Ivashkevich, Oleg A.
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MAGNETIC properties ,CRYSTAL structure ,COPPER ,COORDINATION polymers ,MAGNETIC measurements ,COPPER chlorides - Abstract
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]
- Published
- 2020
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15. Copper(II) Complex of a Urea‐functionalized Pyridyl Ligand: Synthesis, Crystal Structure, and Acetate Binding Properties.
- Author
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Yang, Zaiwen, Li, Chun, Liu, Xiangrong, Zhao, Shunsheng, Qu, Mengnan, Sun, Shasha, Zhang, Zhen, Yang, Zheng, and Chen, Xinjuan
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CRYSTAL structure ,ACETATES ,HYDROGEN bonding interactions ,COPPER ,HYDROGEN bonding - Abstract
A copper(II) acetate complex with a urea‐functionalized pyridyl ligand, [CuL(OAc)2]2·2AcOH (1) [L = N‐(3‐chlorophenyl)‐N'‐(3‐pyridyl) urea], was synthesized by the reaction of L with Cu(OAc)2 in methanol. A zigzag‐shaped hydrogen bond chain of L is obtained via urea N–H···Npyridyl interactions, and a two‐dimensional hydrogen bond network structure is further formed through the C–H···O interaction. In the complex 1, a paddle‐wheel structure is generated by Cu···Oacetate interactions and Cu···Npyridyl interactions. Furthermore, hydrogen bonding chain structure is extended through weak C–H···O hydrogen bond interactions. Through ultraviolet‐visible (UV/Vis) spectroscopy, the acetate binding properties of L in solution were also evaluated. Variable temperature magnetic susceptibility measurement indicates that the metal complex 1 displays antiferromagnetic coupling property. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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16. Synthesis of β‐Ketoiminato Copper(II) Complexes and Their Use in Copper Deposition.
- Author
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Preuß, Andrea, Korb, Marcus, Rüffer, Tobias, Bankwitz, Jörn, Georgi, Colin, Jakob, Alexander, Schulz, Stefan E., and Lang, Heinrich
- Abstract
The template synthesis of ethylenediamine (1) with 2‐acetylcyclopentanone (2) and [Cu(OAc)2·H2O] (5) produced [Cu(1‐(2‐cC5H6(O))C(Me)NCH2)2)] (6) in 82 % yield. Reaction of 5 with bis(benzoylacetone)diethylenetriamine (7, = LH)[1] gave [Cu(μ‐OAc)(L)(H2O)]2 (8). The solid‐state structures of 6 and 8 were determined confirming that 8 possesses intra‐ and intermolecular hydrogen bonds resulting in a dimer formation. The thermal behavior of 6–8 was studied by TG and TG‐MS. Under oxygen CuO was formed, whereas under Ar Cu/Cu2O (6) or Cu (8) was obtained. Complex 6 was used as CVD precursor for Cu and Cu‐oxide deposition (substrate temp., 400–500 °C, N2, 60 mL·min–1; O2, 60 mL·min–1; pressure, 0.87–1.5 mbar). The as‐obtained deposits show separated particles of different appearance at the substrate surface as evidenced by SEM. Non‐volatile 8 was applied as spin‐coating precursor for Cu and CuO formation [conc. 0.25 mol·L–1; volume 0.2 mL; 3000 rpm; depos. time 2 min; heating rate 50 K·min–1; holding time 60 min (Ar), 120 min (air) at 800 °C]. The samples on silicon consist of granulated particles (Ar) or are non‐dense with a grainy topography (air). EDX and XPS measurements confirmed the formation of Cu (Ar) or CuO (O2) with up to 13 mol‐% C impurity. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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17. Synthesis, Characterization, Structural Description, Micellization Behavior, DNA Binding Study and Antioxidant Activity of 4, 5 and 6‐Coordinated Copper(II) and Zinc(II) Complexes.
- Author
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Iqbal, Muhammad, Karim, Amir, Ali, Saqib, Bilal, Hazrat, and Rehman, Ata Ur
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ZINC compounds synthesis ,COPPER ,ZINC ,MEASUREMENT of viscosity ,DNA ,ANIONIC surfactants ,DNA synthesis - Abstract
Four mononuclear copper(II) and zinc(II) complexes were synthesized by the reaction of copper and zinc salts with 3,4‐dichlorophenylactic acid, 2‐bromophenylactic acid, biphenylacetic acid (O‐donor ligand) and bipyridine (N‐donor ligands) having the general formulae [(L)2Cu(bp)(H2O)] (1), [(BpA)2Cu(bp)] (2), [(L)2Zn(bp)(H2O)] (3) and [(L*)2Zn(bp)] (4) (L = 3,4‐dichlorophenylacetate, L* = 2‐bromophenylacetate bp = bipyridine, and BpA = biphenylacetate). Structures of all compounds were characterized through FT‐IR spectroscopy and X‐ray diffraction analysis. FT‐IR spectra of all complexes confirmed the binding mode of Cu‐O and Zn‐O. XRD data revealed that complexes 1–3 exhibited distorted octahedral arrangement, whereas complex 4 has a distorted tetrahedral environment. Micellization behavior was examined with anionic surfactant (SDS) by conductance measurement as well as absorption spectral analysis. DNA binding study was assessed through viscosity measurement and UV/Vis spectrophotometry. DPPH free radical scavenging assay was measured by UV/Vis spectrophotometry. The results showed nice biological potential of all the complexes. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
18. Supramolecular Ammine‐Copper rac‐BINOLAT Salts through in‐situ R‐ or S‐BINOL Racemization.
- Author
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Wisser, Barbara, Labahn, Andreas, Näther, Christian, and Janiak, Christoph
- Subjects
RACEMIZATION ,BRIDGING ligands ,HYDROGEN bonding ,MOIETIES (Chemistry) ,SALTS ,RACEMIC mixtures - Abstract
The molecule rac‐1,1'‐binaphthalene‐2,2'‐diol (rac‐1,1'‐bi‐2‐naphthol, rac‐BINOL) shows a propensity for supramolecular, charge‐assisted O–H···O– hydrogen‐bonded strand formation when crystallized with its deprotonated form BINOLAT2– and Cu2+ in conc. ammonia. The naphthyl‐paneled cavities in the {(rac‐BINOLAT2–)(rac‐BINOL)2} strands host the [Cu(NH3)5]2+‐guest cation through second‐sphere N–H···O hydrogen bonding in the structure of [Cu(NH3)5]2+(rac‐BINOLAT2–)(rac‐BINOL)2. Decreasing the copper(II) and ammonia concentrations in the crystallization leads to {(rac‐BINOLAT2–)(rac‐BINOL)} strands, in which rac‐BINOLAT2– coordinates to two copper(II) atoms in the structure of [Cu(NH3)2(μ‐rac‐BINOLAT2–‐κ2O,O':κO)]2(rac‐BINOL)2. In the {Cu2+(NH3)2} moiety two BINOLAT‐oxide atoms act as bridging ligands. Both copper structures could be obtained by using the racemic rac‐BINOL or the enantiomeric R‐ or S‐BINOL, through an in‐situ racemization of the latter. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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19. Straightforward Preparation of a Solid‐state Luminescent Cu11 Polymetallic Assembly via Adaptive Coordination‐driven Supramolecular Chemistry.
- Author
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Evariste, Sloane, El Sayed Moussa, Mehdi, Wong, Hok‐Lai, Calvez, Guillaume, Yam, Vivian Wing‐Wah, and Lescop, Christophe
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SUPRAMOLECULAR chemistry ,ADAPTIVE control systems ,COORDINATE covalent bond - Abstract
The tridentate dpmp ligand was reacted with CuI salt and cyano ligand affording selectively and unexpectedly the polymetallic Cu11 complex 2 along one‐step reaction. The formation of this derivative 2 can be explained by self‐assembling processes controlled by adaptive coordination‐driven supramolecular chemistry. The solid‐state photophysical behavior of 2 was studied suggesting TADF properties. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
20. Synthesis, X‐ray Structures, and Photoluminescence of the Octahedral Cu4I4 Cluster with Bulky Bidentate Bis(phosphanyl)amine Ligand.
- Author
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Al‐Masri, Harbi Tomah and Almejled, Akram Ali
- Subjects
PHOTOLUMINESCENCE ,X-rays ,EXCITED states ,CHARGE transfer ,CHEMICAL bond lengths - Abstract
The reaction of C10H7‐1‐N(PPh2)2 (1) with two equivalents of CuI in acetonitrile resulted in the formation of octahedron Cu4I4[1]2 complex (2). The crystal structure of 2 showed it adopted a rare octahedral arrangement. The rectangular Cu4 plane is μ4‐capped by two of the iodides and is placed in axial positions above and below the Cu4‐plane form an octahedron, whereas the other two iodides are bonded to two copper atoms in a μ2‐fashion. The luminescence of complex 2 arises from a triplet halide‐to‐ligand charge transfer (3XLCT) excited state and 3CC (Cu4I4 cluster‐centered) excited state are not involved in the luminescence by the rigid bidentate ligand 1 in spite of the short CuI–CuI bond length. Complex 2 was identified and characterized by multinuclear NMR (1H, 13C, 31P NMR) and IR spectroscopy. Crystal structure determinations of 1 and 2 were carried out. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
21. Copper(I) Complexes of Anionic Tridentate CNC Pincer Ligands.
- Author
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Adiraju, Venkata A. K., Jin, Weichang, Yousufuddin, Muhammed, and Dias, H. V. Rasika
- Subjects
COPPER ,CRYSTAL structure ,THERAPEUTIC use of lithium - Abstract
New monoanionic CNC pincer ligands, [N{SiMe2CH2(RIm)}2]– (R = tBu, iPr, Ph) featuring three different N‐heterocyclic carbenes and a disilylamido moiety is reported. Treatment of the lithium salt of [N{SiMe2CH2(RIm)}2]– with CuIOTf afforded the corresponding copper complexes [N{SiMe2CH2(RIm)}2]Cu in 41–56 % yield. X‐ray crystal structures of [N{SiMe2CH2(RIm)}2]Cu show that they are monomeric and feature three‐coordinate, pseudo T‐shaped copper(I) sites. The X‐ray crystal structure of one of the precursor lithium complexes, [N{SiMe2CH2(tBuIm)}2]Li is also presented. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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22. Synthesis and Structures of Four Metal‐Organic Coordination Compounds with Isomeric Tripodal Ligands.
- Author
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Qi, Zhao‐Peng, Xu, Wen, Diao, Xiang‐Yang, Li, Liang‐Qing, and Chen, Lei
- Subjects
ORGANOMETALLIC compounds ,X-ray crystallography ,LIGANDS (Chemistry) ,METAL ions ,WATER ,COORDINATION compounds - Abstract
Four new metal‐organic coordination compounds [Ni(L4)2](ClO4)2·2H2O (1), [Cu2(L4)2(H2O)2(Cl)](Cl)3·5H2O (2), [Cu2(L3)2(H2O)(Cl)](Cl)2·(NO3)·6H2O (3), and [Cu(L3)(H2O)(NO3)](NO3)·H2O (4), were synthesized and characterized by X‐ray crystallography with two isomeric tripodal ligands N1‐(2‐amino‐ethyl)‐N1‐pyridin‐3‐ylmethyl‐ethane‐1,2‐diamine (L3) and N1‐(2‐amino‐ethyl)‐N1‐pyridin‐4‐ylmethyl‐ethane‐1,2‐diamine (L4), respectively. It was found that coordination compound 1 exhibits mononuclear structure, and coordination compound 2 displays a one dimensional (1D) zigzag chain structure. Coordination compound 3 shows interesting cyclic hexanuclear structure, whereas coordination compound 4 is a 1D zigzag chain structure. The results indicate that metal ions, organic ligands, and anions have remarkable influence on the formation and structures of the coordination compounds. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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23. Synthesis, Crystal Structure, Thermal Stability, Magnetic Property, and Biological Activity of a New Copper(II) Complex Based on 1,2,4‐Benzenetricarboxylic Acid and 2,2′‐Bipyridine.
- Author
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He, Xiong, Chen, Fang, Zhang, Dan, Li, Yan, Yang, Hong‐Li, and Zhang, Xiu‐Qing
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COPPER ions ,MAGNETIC properties ,THERMAL stability ,CRYSTAL structure ,MAGNETIC susceptibility ,COPPER - Abstract
Based on an asymmetric 1,2,4‐benzenetricarboxylic acid (H3btc) and 2,2′‐bipyridine (bpy), a new CuII complex, Cu2(H2btc)4(bpy)2·8H2O (1), was synthesized and structurally characterized by single‐crystal X‐ray diffraction, hirshfeld surface (HS) analysis, IR spectroscopy, powder X‐ray analysis, thermal gravimetry analysis (TGA), magnetic susceptibility, EPR measurement, and UV/Vis spectrometry. Complex 1 shows a dinuclear copper structure. The CuII of each dinuclear moiety are in a slightly distorted square‐pyramidal environments. Magnetic susceptibility of 1 shows a ferromagnetic coupling between both metal atoms. The interaction of 1 with bovine serum albumin (BSA) is investigated using UV/Vis, fluorescence spectroscopic methods. The CuII complex shows strong binding propensity in albumin binding study. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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24. Gallium and Indium Alkoxides with Hydride, Cyclopentadienediide and Copper(I) tert‐Butoxide as further Components.
- Author
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Veith, Michael, Summa, Daniela, Annel, Uwe, and Huch, Volker
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GALLIUM ,INDIUM ,ALKOXIDES ,COPPER ,GALLIUM selenide ,HYDRIDES ,ACETONE ,DOUBLE bonds - Abstract
Gallium hydride stabilized by the base quinonuclidine reacts with acetone under addition of the Ga‐H function to the carbon–oxygen double bond yielding (HGa)5(OiPr)8O (1) as isolable compound. (HGa)5(OiPr)8O may be formally split in to four entities of HGa(OiPr)2 and one entity HGaO. The inner atomic skeleton of 1 is a novel Ga5O9 heterocluster with gallium atoms occupying the corners of a distorted trigonal bi‐pyramid, an oxygen atom in the center and the remaining alcoholate oxygen atoms bridging eight of the nine edges of the bi‐pyramid (X‐ray diffraction analysis). Potassium indium alkoxide KIn(OtBu)4 has been used to synthesize several new compounds like In4(OtBu)8(C5H4)2 (2), (py)2CuIn(OtBu)4 (3), and [CuIn(OtBu)4]2 (4) by reaction with TiCl2cp2 (2) and CuCl (3, 4). All compounds were characterized by spectroscopic means and by X‐ray structure analyses revealing novel polycyclic structures. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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25. First Copper(I) and Silver(I) Complexes Containing Phosphanylphosphido Ligands.
- Author
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Ziółkowska, Aleksandra, Brauer, Sandra, and Ponikiewski, Łukasz
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LIGANDS (Chemistry) ,COPPER ,NUCLEAR magnetic resonance spectroscopy ,SILVER ,X-ray diffraction ,TRANSITION metal complexes - Abstract
Three new complexes with phosphanylphosphido ligands, [Cu4{μ2‐P(SiMe3)‐PtBu}4] (1), [Ag4{μ2‐P(SiMe3)‐PtBu2}4] (2) and [Cu{η1‐P(SiMe3)‐PiPr2}2]–[Li(Diglyme)2]+ (3) were synthesized and structurally characterized by X‐ray diffraction, NMR spectroscopy, and elemental analysis. Complexes 1 and 2 were obtained in the reactions of lithium derivative of diphosphane tBu2P‐P(SiMe3)Li·2.7THF with CuCl and [iBu3PAgCl]4, respectively. The X‐ray diffraction analysis revealed that the complexes 1 and 2 present macrocyclic, tetrameric form with Cu4P4 and Ag4P4 core. Complex 3 was prepared in the reaction of CuCl with a different derivative of lithiated diphosphane iPr2P‐P(SiMe3)Li·2(Diglyme). Surprisingly, the X‐ray analysis of 3 revealed that in this reaction instead of the tetramer the monomeric form, ionic complex [Cu{η1‐P(SiMe3)‐PiPr2}2]–[Li(Diglyme)2]+ was formed. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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26. Enhancement of Photocatalytic Activity of Sodium Bismuth Titanate by Doping with Copper, Silver, and Tin Ions.
- Author
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Kurra, Sreenu, Venkataswamy, Perala, Ravi, Gundeboina, Sudhakar Reddy, Chandhiri, Jaganmohan Reddy, Boggu, and Vithal, Muga
- Subjects
TITANATES ,BISMUTH ,BISMUTH titanate ,COPPER ,IONS ,TIN ,SODIUM compounds - Abstract
Perovskite type oxides, sodium bismuth titanate (Na0.5Bi0.5TiO3), and Ag+, Cu2+, and Sn2+ doped Na0.5Bi0.5TiO3 were prepared by pechini and ion exchange methods, respectively. Photocatalytic activities of these catalysts were tested by decomposition of methylene blue (MB) under visible light irradiation. Results showed that the photocatalytic activity of metal ion doped Na0.5Bi0.5TiO3 was higher than undoped Na0.5Bi0.5TiO3. Relatively high photocatalytic performance of Ag+‐doped Na0.5Bi0.5TiO3 is mainly ascribed to the efficient separation of electron‐hole (e–, h+) pairs, lower bandgap energy and the creation of active hydroxyl radicals (•OH). Further, the Ag+‐doped Na0.5Bi0.5TiO3 catalyst showed good reusability up to four cycles. A possible mechanism for the enhanced photocatalytic performance was proposed. The synthesized photocatalysts were characterized by XRD, SEM, EDS, XPS, FT‐IR, and UV/Vis DRS techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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27. Two Bulky Conjugated 4′‐(4‐Hydroxyphenyl)‐4,2′:6′,4′′‐terpyridine‐based Layered Complexes: Synthesis, Structure, and Photocatalytic Hydrogen Evolution Activity.
- Author
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Zhu, Shuang, Dai, Xue‐Jiao, Wang, Xiu‐Guang, Cao, Ying‐Yu, Zhao, Xiao‐Jun, and Yang, En‐Cui
- Subjects
ORGANOPLATINUM compounds ,INTERSTITIAL hydrogen generation - Abstract
Two new layered complexes with the formulas of {[Cu(H2O)(HL)2Cl](NO3)}n (1) and {[Cu(H2O)2(HL)2](NO3)2}n (2) were solvothermally synthesized by the reactions of the bulky conjugated 4′‐(4‐hydroxyphenyl)‐4,2′:6′,4′′‐terpyridine ligand (HL) with different CuII salts, which were further used as photocatalysts to achieve hydrogen production from water splitting. Single‐crystal structural analyses reveal that both complexes feature coplanar (4 4) layers with different connection manners between the HL extended Z‐shaped chains. More interestingly, 1 possessing more negative conduction band potential and higher structural stability exhibits a large hydrogen production rate of 2.43 mmol·g–1·h–1, which is four times higher than that of 2. Thus, the CuII‐based coordination polymers modified by the bulky conjugated organic ligand can become potentially promising non‐Pt photocatalysts for hydrogen production from water splitting. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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28. Crystal Structure and Structural Transformation of [(CH3)3NH]2[CuZn(CN)5].
- Author
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Miyahara, Kana, Yoshida, Jun, Yuge, Hidetaka, and Nishikiori, Shin‐ichi
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CRYSTAL structure ,NUCLEAR magnetic resonance spectroscopy ,CYANIDES ,COORDINATION polymers ,ATMOSPHERIC pressure - Abstract
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]
- Published
- 2019
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29. Syntheses, Structures, and Catalytic Properties of Three Copper(II) Coordination Polymers Based on 2,3,5,6‐Tetrafluoro‐1,4‐bis(triazole‐ylmethyl)benzene and Benzene Carboxylate Ligands.
- Author
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Tian, Feng, Shen, Nan, Chen, Sheng‐Chun, Jiang, Li‐Ting, Chen, Qun, and He, Ming‐Yang
- Subjects
POLYMERS ,TETRAFLUOROBORATES ,BENZENE ,CARBOXYLATES ,LIGANDS (Chemistry) - Abstract
Three new mixed‐ligand coordination polymers of CuII, namely, [Cu(Fbtx)(L1)(H2O)]n (1), [Cu(Fbtx)0.5(HL2)(H2O)2]n (2), and {[Cu(Fbtx)1.5(HL3)(H2O)]·H2O}n (3) [Fbtx = 2,3,5,6‐tetrafluoro‐1,4‐bis(1,2,4‐triazole‐1‐ylmethyl)benenze, H2L1 = terephthalic acid, H3L2 = trimesic acid, NaH2L3 = 5‐sulfoisophthalic acid monosodium salt], were hydrothermally synthesized and structurally characterized by elemental analysis, IR spectra, and single‐crystal and powder X‐ray diffraction techniques. All the complexes have a two‐dimensional (2D) coordination layer structure. Of these, 1 displays a planar 44‐sql structure whereas both 2 and 3 are highly undulated 63‐hcb nets. Moreover, their thermal stability and catalytic behaviors in the aerobic oxidation of 4‐methoxybenzyl alcohol were also investigated as well. The results indicate that the benzene dicarboxylate ligands have an effective influence on the structures and catalytic properties of the resulting coordination polymers. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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30. Two New MOFs Based on Cu2 Paddlewheel Units and Biphenyltetracarboxylate Ligands with a Different Degree of Fluorination.
- Author
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Stastny, Carina and Ruschewitz, Uwe
- Subjects
CRYSTAL structure ,CHEMICAL reactions ,METAL-organic frameworks ,MOLECULAR structure ,DENSITY functional theory - Abstract
Two new MOFs (metal‐organic frameworks), namely 3∞[Cu2(H2O)2(L)]·3DMF·H2O [L = 4‐fluoro‐biphenyl‐3,3′,5,5′‐tetracarboxylate (4‐mF‐BPTC4–) and 4,4′‐difluoro‐biphenyl‐3,3′,5,5′‐tetracarboxylate (4,4′‐dF‐BPTC4–)] termed UoC‐1(1F) and UoC‐1(2F) (UoC ≡ University of Cologne), were synthesized by solvothermal reactions in DMF. The crystal structure of UoC‐1(1F) was solved and refined from X‐ray single crystal data (Imma, Z = 4). The X‐ray powder diffraction data of UoC‐1(2F) confirmed that both MOFs are isostructural. In their crystal structures each of the four carboxylate groups of the BPTC4– linker is involved in a Cu2 paddlewheel unit leading to a 3D structure with high porosity, which was confirmed by N2 gas sorption measurements revealing specific surface areas of SBET = 1256 m2·g–1 [UoC‐1(1F)] and 1162 m2·g–1 [UoC‐1(2F)] after activation at 120 °C for 72 h. Higher activation temperatures lead to a decomposition of the framework and significantly decreased specific surface areas. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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31. Microwave‐assisted Synthesis, Crystal Structures, and Thermal Stability of C11H10N2Cu2Br3 and C22H20N4Cu8I10.
- Author
-
Deng, Min, Wu, Yuandong, Rao, Pinhua, Zhang, Wenqi, Wang, Runkai, and Doert, Thomas
- Subjects
CRYSTAL structure ,COPPER ,HALIDES ,LIGANDS (Chemistry) ,NANOPARTICLES - Abstract
Complexes of C11H10N2Cu2Br3 (1) and C22H20N4Cu8I10 (2) [C22H20N4 = 1,1"‐(1,2‐ethanediyl)‐bis‐4,4′‐bipyridinium] were synthesized via the microwave‐assisted solvo‐thermal reactions of C22H20N4Br2, CuSO4·5H2O, and NaX (X = Br, I) and characterized by XRD, FTIR, and thermogravimetric analysis. The crystal structures were determined by single‐crystal X‐ray diffraction analyses. C11H10N2Cu2Br3 crystallized in the monoclinic space group C2/c (no. 15) with lattice parameters a = 24.658(3) Å, b = 6.71(9) Å, c = 17.368(9) Å, β = 98.274(1)°, V = 2847.7(1) Å3, whereas C22H20N4Cu8I10 crystallized in the monoclinic space group P21/n (no. 14) with lattice parameters a = 7.392(2) Å, b = 20.809(7) Å, c = 25.412(7) Å, β = 92.06(8) °, V = 3906.6(8) Å3. Complex 1 showed a 2D layered structure composed of [Cu4Br6]– chains connected via 1,1"‐(1,2‐ethanediyl)‐bis‐4,4′‐bipyridinium ligands. Complex 2 possessed a 3D framework, in which puckered [Cu8I10]2– layers were linked by organic ligands. The thermogravimetric analysis indicated that both two complexes were stable up to 230 °C and 170 °C, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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32. Selective Synthesis and Complexation of Novel N,N′‐Alkylene‐Bridged Bis(5‐pyridyltetrazole).
- Author
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Voitekhovich, Sergei V., Mosalkova, Anastasiya P., Lyakhov, Alexander S., Ivashkevich, Ludmila S., Schmorl, Sara, Kersting, Berthold, and Ivashkevich, Oleg A.
- Subjects
TETRAZOLES ,LIGANDS (Chemistry) ,HETEROCYCLIC compounds synthesis ,REGIOSELECTIVITY (Chemistry) ,ALKYLATION ,COPPER ions ,X-ray diffraction - Abstract
A novel N,N′‐alkylene‐bridged bis(5‐pyridyltetrazole) ligand, namely 2,5‐bis[5‐(2‐pyridyl)‐tetrazol‐2‐yl]‐2,5‐dimethylhexane (bpt), was prepared by regioselective N2‐alkylation of 5‐(2‐pyridyl)tetrazole with 2,5‐dimethylhexane‐2,5‐diol in perchloric acid. The ligand bpt was found to react with copper(II) chloride to give the dinuclear complex [Cu2(bpt)Cl4]. According to single‐crystal X‐ray analysis of the complex, bpt acts as a chelating ligand, coordinated by the metal through the tetrazole ring N4 and the pyridine ring nitrogen atoms. In the complex molecule, two copper atoms are linked by double chlorido bridges, and ligand bpt plays the role of the third bridge. The temperature‐dependent magnetic susceptibility measurements of the complex revealed that the copper(II) ions were weakly antiferromagnetically coupled showing a coupling constant J of –1.04 cm–1. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
33. A New Heterometallic CuII‐LaIII Metal‐organic Framework: Crystal Structure, Adsorption of Light Hydrocarbons and Anti‐gastric Cancer Activity.
- Author
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Zhang, Lian‐Xing, Han, Xia, Yang, Yan, Zhang, Qiu‐Ning, Wang, Jia, and Li, Zhi‐Hu
- Subjects
METAL-organic frameworks ,COPPER compounds ,CRYSTAL structure ,ANTINEOPLASTIC agents ,STOMACH cancer treatment ,GAS absorption & adsorption ,SINGLE crystals ,X-ray diffraction ,CRYSTALLOGRAPHY - Abstract
The solvothermal self‐assembly reaction of CuCl2, LaCl3, and H2tdc afforded a new heterometallic compound, namely [CuLa2(tdc)4(H2O)(DMA)2]n (1) (H2tdc = thiophene‐2,5‐dicarboxylic acid, DMA = N,N′‐dimethylacetamide). Single crystal X‐ray diffraction analysis revealed that compound 1 features a 3D framework based on 1D heterometallic rod‐shaped CuII‐LaIII‐carboxylate chains. The porous framework of the desolvated samples (denoted as 1′) can be easily obtained via the heat treatment process at 200°C for 2 h. Gas adsorption investigations revealed that 1′ exhibits good light hydrocarbons adsorption performance. In addition, the anticancer activities of this heterometallic complex were evaluated via the MTT assay. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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34. A Study on FeII, ZnII and CuII Complexes with Novel Tridentate Bis(pyrazolyl)methane Ligands.
- Author
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Herber, Ulrich, Moegling, Julian, Siris, Rita, Hoffmann, Alexander, Mayer, Peter, Göbel, Christoph, Lochenie, Charles, Weber, Birgit, and Herres‐Pawlis, Sonja
- Subjects
LIGANDS (Chemistry) ,METHANE synthesis ,PYRAZOLYL compounds ,COORDINATION compounds ,ELECTRON spin states ,IRON compound synthesis - Abstract
The ligand class of tridentate bis(pyrazolyl)methanes was extended via the syntheses of HC(3,5‐EtPz)2Py. This ligand is the first of its kind with a homogeneous 3,5‐functionalization with large substituents. On the basis of 3,5‐functionalized ligands we were able to synthesize 15 novel complexes with FeII, ZnII, and CuII salts. Herein we present an extensive coordination chemistry study, that focuses on the influences of different metals, ligands, and counterions on the coordination mode and on the spin state in case of FeII complexes. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
35. The Curious Case of a Phenylated Guanidinoquinoline Ligand: Synthesis, Complexes and ATRP Properties of DMEG6phqu.
- Author
-
Rösener, Thomas, Kröckert, Konstantin, Hoffmann, Alexander, and Herres‐Pawlis, Sonja
- Subjects
LIGANDS (Chemistry) ,GUANIDINES ,METAL complexes ,POLYMERIZATION ,COPPER - Abstract
In previous studies, copper halide complexes of the guanidinoquinoline (GUAqu) ligands 1,3‐dimethyl‐N‐(quinolin‐8‐yl)‐imidazolidin‐2‐imine (DMEGqu) and 1,1,3,3‐tetramethyl‐2‐(quinolin‐8‐yl)‐guanidine (TMGqu) were successfully implemented in atom transfer radical polymerization (ATRP) and could be further enhanced by introduction of alkyl substituents at C6 position of the quinoline backbone. Herein, the ligand DMEG6phqu is presented. The quinoline backbone of this ligand is equipped with a phenyl substituent at C6 position. This study deals with the influence of the phenyl substituent on solubility and molecular structural properties of DMEG6phqu CuI and CuII bromide complexes. In contrast to previously reported systems, the CuIBr complex of DMEG6phqu crystallizes as a trigonal coordinated monochelate complex. However, NMR and UV/Vis spectroscopic experiments indicate that DMEG6phqu forms a bischelate species in solution. The influence of the substituent on the complex redox potential and ATRP equilibrium constant KATRP is discussed. In contrast to expectations, it turned out that copper halide complexes of DMEG6phqu are completely insoluble in the apolar monomer styrene. However, ATRP kinetics were performed in solution and the results are compared to previous studies. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
36. Investigation of Chromophoric Behavior of Water‐Soluble LaIII‐CuII Polynuclear Metallamacrocyclic 15‐MC‐5 Complex.
- Author
-
Zabrodina, Galina S., Katkova, Marina A., Samsonov, Maxim A., and Ketkov, Sergey Yu.
- Subjects
WATER-soluble polymers ,CHROMOPHORES ,X-ray crystallography ,METALLACROWNS ,ABSORPTION spectra - Abstract
The visible absorption spectrum of the water soluble polynuclear metallamacrocyclic La
III ‐CuII complex La(H2 O)3 [15‐MCCu(II)Phalaha ‐5](Cl)3 (1) based on α‐phenylalaninehydroxamic acid appears to be solvent‐ and ion‐sensitive. The copper(II) d–d transitions of the complex 1 dissolved in methanol, ethanol, water, dimethylformamide, dimethylsulfoxide, pyridine, and N‐methylpyrrolidone were studied. The chromophoric behavior of complex 1 was investigated in the presence of the Cl– , Br– , I– , HSO4 – , CO3 2– , HCO3 – , H2 PO4 – , CN– , SCN– , and N3 – anions. A considerable change of the d–d transition of the central copper(II) atom was observed for the strongly coordinating cyanide and azide anions. In the presence of HSO4 – , the d–d intensity of copper(II) also decreased significantly. The molecular structure of La2 (H2 O)7 [15‐MCCu(II)Phalaha ‐5]2 (SO4 )4 (2), obtained as result of the substitution of the coordinated water molecules in 1 by the SO4 2– anions, was investigated by X‐ray crystallography. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
37. Copper(II)‐induced Fluorescence Quenching of a BODIPY Fluorophore.
- Author
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Herten, Dirk‐Peter, Haderspeck, Andreas, Braun, Felix, and Wadepohl, Hubert
- Subjects
COPPER ,FLUORESCENCE quenching ,FLUORESCENCE spectroscopy ,DIPYRROMETHANES ,METAL ions - Abstract
The ongoing developments in fluorescence microscopy have pushed the interest in new fluorescent probes with specific properties. Aside of controlling emissive states by light irradiation, defined control by changing the chemical environment has come into focus. In this context, we designed a fluorescent probe by conjugation of bipyridine, acting as sensor for Cu
II , to a BODIPY derivative at the shortest possible distance between sensor and chromophore. Herein, we present the synthesis of the BODIPY probe along with its crystal structure. We found a strong dependence of absorption and emission upon CuII complex formation decreasing the fluorescence quantum yield to ca. 1 % in respect to the pure probe. We hypothesize that further functionalization with a linker could make this compound and interesting probe for fluorescence microscopy. [ABSTRACT FROM AUTHOR]- Published
- 2018
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- View/download PDF
38. Hybrid α‐Diimine/Bis(chalcogenoether) Ligands for Copper(I) and Copper(II) Complexes.
- Author
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Bubrin, Martina, Kvapilová, Hana, Fiedler, Jan, Ehret, Fabian, Záliš, Stanislav, and Kaim, Wolfgang
- Subjects
LIGANDS (Chemistry) ,IMINES ,PYRAMIDAL tract ,OXYGEN atom transfer reactions ,ELECTROCHEMISTRY - Abstract
The new ligands L = 1,4‐bis(2‐methylchalcogenophenyl)‐2,3‐dimethyl‐1,4‐diaza‐1,3‐diene [chalcogen = O (1), S (2) or Se (3)] have been studied in their coordination behavior towards Cu
I and CuII . Whereas the O‐ether containing ligand forms complex ions [Cu(L)2 ]n+ = 4n+ , with exclusive N‐coordination (n = 1) or N and weaker O coordination (n = 2), the species with E = S or Se contain tetradentate ligands in [Cu(L)]+ (5+ , 6+ ) and [Cu(L)L′]n+ [n = 1, L′ = TfO– (E = S) or n = 2 and L′ = H2 O (E = Se)]. Molecular structures in the crystals of 5+ and 6+ show distorted tetrahedral N coordination at the metal and innocently behaving α‐diimine functions, in agreement with spectroscopic and computational data. The copper(II) ions [Cu(L)L′]2+ with one tetradentate ligand L = 2 or 3 exhibit a square‐pyramidal configuration at the metal. Two isolated crystalline forms of 42+ show weak coordination (2.636–2.96 Å) of three or four ether oxygen atoms, resulting in 4+3 or 4+4 coordination arrangements for N and O donors, respectively. In agreement with the rather different CuI and CuII structures the electrochemical oxidation of the copper(I) complexes and the reduction of the corresponding CuII species reveal an ECEC behavior within a square scheme, whereas the reduction of the CuI compounds, most likely at the diimine site, proceeds irreversibly. UV/Vis spectroelectrochemical results showing intense MLCT and IL absorptions were analyzed with the help of TD‐DFT calculations. [ABSTRACT FROM AUTHOR]- Published
- 2018
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39. Structure and Magnetic Properties of a 2D Paddle-wheel Dinuclear[Cu2] Cluster-based Polymer with 1,1-Cyclohexanediacetate Ligand.
- Author
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Li, Feng, Liu, Kai, Fan, Shiwen, Qin, Tingting, Xiong, Suhua, and Wang, Jingjing
- Subjects
COPPER ,POLYMERIZATION ,SINGLE crystals ,X-ray diffraction ,ANTIFERROMAGNETIC materials ,CUPROUS oxide - Abstract
One new two-dimensional (2D) Cu
II polymer [Cu(CHDA)(H2 O)]n (1) was synthesized solvothermally based on 1,1- cyclohexanediacetic acid (H2 CHDA) ligand. Single-crystal X-ray diffraction analysis reveals that 1 has a 2D framework structure consisting of paddle-wheel dinuclear [Cu2 ] cluster unit and CHDA2- connector, which bears a 4-connected sql network with Schläfli symbol of (44 .6²). Magnetic studies indicate the presence of strong antiferromagnetic coupling (J = -302 cm-1 ) between the two CuII ions in the paddlewheel dicopper(II) entity. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
40. Encapsulation of 5-Fluorouracil in a Copper(II)-based Porous Metal-organic Framework: Drug Delivery and Inhibiting Human Spinal Cord Tumor Cells.
- Author
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Li, Rongrui, Liu, Shichen, Tang, Qingxi, Wang, Tianshu, Xie, Yunchuan, and Zhai, Raosheng
- Subjects
FLUOROURACIL ,SPINAL cord tumors ,METAL-organic frameworks ,DRUG delivery systems ,CONTROLLED release drugs ,POROUS metals - Abstract
Solvothermal reaction of a semirigid tricarboxylic acid with Cu(NO
3 )2 ·3 H2 O gives rise to a robust microporous metal-organic framework with the formula {[Cu2 (OH)bcb](DMF)2 (H2 O)3 }n (1) [H3 bcb = 3,5-bis((4'-carboxylbenzyl)-oxy)benzoic acid, DMF = N,Ndimethylformamide]. Its structure was determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analyses. The efficient encapsulation of an anticancer drug 5-fluorouracil (5-Fu) on the desolvated 1 (1a) was studied by both grand canonical Monte Carlo (GCMC) simulation and drug release experiments. In addition, in vitro anticancer activity of compounds 1 and 5-Fu loaded 1a were also evaluated using MTT assay. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
41. Crystal Structure and Characterization of Two Layered Copper(II) Coordination Polymers with Anions of 3-Phosphonopropionic Acid and (RS)-2-Phosphonobutyric Acid.
- Author
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Köferstein, Roberto, Arnold, Michael, and Robl, Christian
- Subjects
CRYSTAL structure ,COPPER ,COORDINATION polymers ,PROPIONIC acid ,BUTYRIC acid ,AQUEOUS solutions - Abstract
Blue single crystals of Cu[μ
3 -O3 P(CH2 )2 COOH]·2H2 O (1) and Cu[(RS)-μ3 -O3 PCH(C2 H5 )COOH]·3H2 O (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 [O3 P(CH2 )2 COOH]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 [O3 P(CH2 )2 COOH]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 [O3 PCH(C2 H5 )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 [O3 PCH(C2 H5 )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]- Published
- 2018
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42. Self-Assembly of Discrete Copper(I)-Halide Complexes with Diacylthioureas.
- Author
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Hou, Xianhui, Wang, Fanfan, Han, Li, Pan, Xia, Li, Haipu, Yang, Ying, and Roesky, Herbert W.
- Subjects
COPPER compounds ,X-ray diffraction ,ANIONS ,NUCLEAR magnetic resonance ,FOURIER transform infrared spectroscopy - Abstract
Three diacylthioureas 1,4-C
6 H4 [C(O)NHC(S)NHAr]2 (Ar = 2,6-iPr2 C6 H3 ) (L1 , 1), 1,3-C6 H4 [C(O)NHC(S)NHAr]2 (L2 , 2), and 1,3- C6 H4 [C(O)NHC(S)NHAr']2 (Ar' = 2,6-Me2C6H3) (L3 , 3) were synthesized and characterized. The CuI complexes from the reactions of bipodal ligands Ln with CuX (X = Cl, Br, I) were structurally investigated by single-crystal X-ray diffraction methods. Treatment of L1 with CuX gave the metallamacrocyclic complexes (L1 CuX)2 [X = Cl (4), Br (5), I (6)] with the ligand to metal in a ratio of 2:2, where both sulfur and halide anions function as terminal substituents. In contrast, when L2 or L3 was reacted with CuBr, the two Ln ligands coordinate to four copper atoms each in a bridging and terminal fashion to yield [Ln(CuBr)2 ]2 [n = 2 (7), 3 (8)]. The obtained S4 Cu4 Br4 core contains all four bromide anions in bridging positions. The reaction of L3 with CuX (X = Cl, I) gave the 3:3 trinuclear complexes (L3 CuX)3 [X = Cl (9) I (10)], interconnected by halide bridges. The obtained diacylthioureas (1-3) and their CuI complexes (4-10) were also characterized by elemental analysis, FT-IR,1 H and13 C NMR spectroscopy. [ABSTRACT FROM AUTHOR]- Published
- 2018
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43. Polymeric Copper(II) Paddlewheel Carboxylate: Structural Description, Electrochemistry, and DNA-binding Studies.
- Author
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Iqbal, Muhammad, Ali, Sqib, and Tahir, Muhammad Nawaz
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CARBOXYLATES ,ELECTROCHEMISTRY ,DNA-binding proteins ,FOURIER transform infrared spectroscopy ,X-ray diffraction - Abstract
A polymeric complex of copper(II) was isolated and purified from the self-assembly of CuSO
4 and 2-phenyl acetate in aqueous medium. It was characterized through FT-IR, UV/Vis, electron spin resonance, electrochemical solution studies, and powder and single crystal XRD techniques. The structure was revealed to consist of directly interconnected dimeric paddlewheel building units without any intervening ligand. This type of polymeric paddlewheel structures are found very rarely. Each copper is lying in a CuO5 square pyramid coordinated by four oxygen atoms in the square base while the axial oxygen belongs to the neighboring paddlewheel. Purity and uniform crystalline nature of the complex was assessed from matching theoretical and experimental powder XRD spectra. ESR spectrum consisted of a broad signal with g value = 2.2427, whereas electrochemical studies revealed diffusion controlled electron transfer processes with diffusion co-efficient = 1.628×10-7 cm2 ·s-1 . The results of spectroscopic techniques support each other. The complex afforded mixed binding mode with DNA yielding DNA-binding constant values of 1.384×104 m-1 and 8.845×104 m-1 using absorption spectroscopy and cyclic voltammetry, respectively. The complex also exhibited significant activity against anti-fungal strain Helminthosporium solani by inhibiting its 75%±2.5 growth. The preliminary studies heralded excellent biological potential of the synthesized complex. [ABSTRACT FROM AUTHOR]- Published
- 2018
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44. Synthesis, Structure, and Magnetic Properties of a Copper(II) Metal-Organic Framework with Biphenyl-2,2',4,4'-tetracarboxylic Acid.
- Author
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Tian, Hua, Jia, Qin-Xiang, Li, Peng, Yang, Qing-Feng, and Gao, En-Qing
- Subjects
COPPER compounds ,METAL-organic frameworks ,BIPHENYL compounds ,X-ray diffraction ,ANTIFERROMAGNETISM - Abstract
The 2D CuII metal-organic framework [Cu
2 (bptc)(H2 O)4 ]n·4nH2 O (1) (H4bptc = biphenyl-2,2',4,4'-tetracarboxylic acid) was hydrothermally synthesized and characterized by single- crystal X-ray diffraction and magnetic measurements. In the structure, bptc4- serves as a twisted Π-shaped organic building block to connect paddlewheel [Cu2 (COO)4 ] dinuclear units and mononuclear units through 2-/2'-carboxylate and 4-/4'-carboxylate, respectively. According to the magnetic analysis using a dimer-plus-monomer model, strong antiferromagnetic coupling is operative within the dinuclear unit (J = -311 cm-1 based on H = -JS1 S2 ), and the compound behaves like a mononuclear molecule at low temperature. [ABSTRACT FROM AUTHOR]- Published
- 2018
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45. Copper(II) Halide Complexes with 1-tert-Butyl-1H-1,2,4-triazole and 1-tert-Butyl-1H-tetrazole.
- Author
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Voitekhovich, Sergei V., Degtyarik, Mikhail M., Lyakhov, Alexander S., Ivashkevich, Ludmila S., and Ivashkevich, Oleg A.
- Subjects
COPPER compounds ,HALIDES ,COORDINATION polymers ,X-ray diffraction ,NUCLEAR magnetic resonance spectroscopy - Abstract
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)
4 X2 ] (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 and13 C 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)2 Cl2 ]n and [Cu(tbtr)2 Br2 ]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)4 Cl2 ] and [Cu(tbtr)4 Br2 ] reveal mononuclear centrosymmetric structure, with octahedral coordination of CuII cations. The tetrazole compound [Cu3 (tbtt)6 Br6 ] is a linear trinuclear complex, in which neighboring copper(II) cations are linked by single bromide bridges. [ABSTRACT FROM AUTHOR]- Published
- 2018
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46. A 2D Supramolecular Network Based on Aromatic π···π Stacking Interactions.
- Author
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Liu, Kuan-Guan, Shan, Qi-De, Nie, Jing, and Yan, Xiao-Wei
- Subjects
FERROCENE ,STACKING interactions ,SUPRAMOLECULAR chemistry ,ORGANOMETALLIC compounds ,ELECTROCHEMICAL analysis - Abstract
Using ferrocenecarboxylic acid (FcCOOH) as organometallic ligand in the synthesis of heterometallic complexes led to the isolation of the compound [(FcCOO)Cu(bpy)
2 ](BF4 )·bpy·CH3 OH. It was characterized by IR spectroscopy, EA, powder XRD, UV, and TGA measurements. Single-crystal X-ray structural analysis revealed that a unique 2D supramolecular network purely formed by aromatic π···π stacking interactions was observed, namely, {[(FcCOO)Cu(bpy)2 ](BF4 )·bpy·CH3OH}Ϋ (1). The solid UV/Vis diffuse reflectance spectrum revealed the optical energy gap of 1 to be 3.54 eV, which is dramatically blue shifted compared with the value of ferrocene. Experimental results of thermal analysis and electrochemical analysis show that 1 has good thermal and better electrochemical stability. [ABSTRACT FROM AUTHOR]- Published
- 2018
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47. Oxocentered Units in Three Novel Rb-Containing Copper Compounds Prepared by CVT Reaction Method.
- Author
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Kornyakov, Ilya V., Krivovichev, Sergey V., and Gurzhiy, Vladislav V.
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COPPER compounds ,CHEMICAL vapor deposition ,CRYSTAL structure ,RUBIDIUM ,HYDROGEN bonding - Abstract
Three novel copper compounds, Rb4Cu4OCl10 (I), Rb[Cu
3 O](SeO3 )2 Cl (II), and RbCu3 (OH)(SeO3 )Cl4 (H2 O)3 (III) were prepared by chemical vapor transport (CVT) reactions method from mixtures of CuO, SeO2 , RbCl, and CuCl2 . The crystal structures of the three compounds were determined by direct methods. Compound I is a Rb analogue of ponomarevite, K4Cu4OCl10. Its crystal structure contains {[OCu4 ]Cl10 }4 - clusters with oxocentered [OCu4 ]6+ tetrahedra as cores. The clusters are linked by the Rb+ cations. The crystal structure of II contains complex {[O2 Cu6 ](SeO3 )4Cl2 }2- layers formed by dimers of edge-sharing [OCu4 ]6+ tetrahedra interlinked via selenite groups and Cl- anions. The crystal structure of III is based upon {[(OH)Cu3 ](SeO3 )}3+ layers formed by the [(OH)Cu3 ]5+ tetrahedra attached to (SeO3 )2- groups. The layers are linked via Cl- anions and via hydrogen bonds to H2O molecules. [ABSTRACT FROM AUTHOR]- Published
- 2018
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48. Cu and Zn Substituted Silicon Clathrates with the Cubic Type-II Structure: Synthesis and Characterization of Cs8Na16Cu3.8Si132.2 and Cs8Na16Zn6.9Si129.1.
- Author
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Schäfer, Marion C. and Bobev, Svilen
- Subjects
X-ray diffraction ,ELECTROMAGNETIC wave diffraction ,CLATHRATE compounds ,COMPLEX compounds ,TERNARY alloys - Abstract
Studies in the systems Cs-Na-Cu-Si and Cs-Na-Zn-Si yielded the novel clathrates Cs
8 Na16 (Cu,Si)136 and Cs8 Na16 (Zn,Si)136 , both with the cubic type-II structure [space group Fd3-m (no. 227), Pearson symbol cF160]. The structures of the title compounds were established from single-crystal X-ray diffraction methods, confirming the complete ordering of the Cs and Na guest atoms. The frameworkbuilding Si atoms are found to be randomly substituted by Cu atoms on framework site 96g, exclusively. In the structure of Cs8 Na16 (Zn,Si)136 , the refinements indicate that the Zn and Si atoms co-occupy two of the three framework sites with notable preference for site 96g over site 32e. The corresponding refined compositions and unit cell parameters are as follows: Cs8 Na16 Cu3.8 Si132.2 (1) [a = 14.7583(15) Å]; Cs8 Na16 Zn6,9 Si129.1 (1) [a = 14.7682(5) Å], respectively. The type-II clathrates can be obtained only from experiments employing both Na and Cs, whereas work in the ternary Cs-Cu-Si, Cs-Zn-Si, Na-Cu-Si, and Na-Zn-Si systems failed to yield any clathrate phases. At the same conditions, exploratory studies in the K-Zn-Si and Rb-Zn-Si systems provided evidence that type-I clathrates are favored. [ABSTRACT FROM AUTHOR]- Published
- 2017
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49. Synthesis, Structural and Energetic Properties of Copper(II) Perchlorate Complex with Aminoguanidine.
- Author
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Mahdavi, Mohammad, Ghani, Kamal, and Nosratzadegan, Keyvan
- Subjects
PERCHLORATES ,COPPER compounds ,AMINOGUANIDINE ,X-ray diffraction ,STOICHIOMETRY ,DIFFERENTIAL scanning calorimetry - Abstract
The complexation of copper(II) perchlorate with aminoguanidine hemesulfate (AGHS) yield related mononuclear complex bis(aminoguanidine)copper(II) perchlorate; [Cu(AG)
2 ](ClO4 )2 (I). The characterization of complex I was done by elemental analysis, electronic spectra, IR studies, and X-ray diffraction. From analytical data, a stoichiometry of 1:2 of metal to ligand was determined for the complex. The structure consists of centrosymmetric square planar [Cu(AG)2 ]2+ cations and perchlorate counterions. The CuII atom is four-coordinate by two imine N atoms and two amine N atoms from two aminoguanidine ligands, forming a slightly distorted square-planar coordination. In the crystal structure, molecules are linked through intermolecular N-H···O hydrogen bonds, forming a network. The thermal decomposition process of this complex was investigated through differential scanning calorimetry (DSC) and the sensitivities toward impact and friction were assessed using a BAM drophammer and a BAM friction tester. [ABSTRACT FROM AUTHOR]- Published
- 2017
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50. Syntheses, Structures, and Magnetic Behavior of New Azide Linked Compounds with One- and Two-Dimensional Structures.
- Author
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Mistry, Subhradeep, Sutter, Jean‐Pascal, and Natarajan, Srinivasan
- Subjects
AZIDE synthesis ,MAGNETIC properties of metals ,ALIPHATIC amine synthesis ,FERROMAGNETIC materials ,COPPER compounds - Abstract
Three azide based compounds were synthesized employing aliphatic amines as site blocking agents: [Ni(N
3 )(C6 H16 N2 )2 ]ClO4 (I) [C6 H16 N2 = N,N'-diethylethylenediamine (DEDA)], [Cu8 (N3 )16 (C6 H18 N4 )2 ] (II) [C6 H18 N4 = tris(2-aminoethyl) amine (TREN)], and [Cu7 (N3 )14 (C7 H19 N3 )2 ]·2H2 O (III) [C7 H19 N3 = 3,3'-diamino-N-methyldipropylamine (DMDA)]. The compounds I and II have one-dimensional structure and III has a two-dimensional structure. Compound I is a simple linear cationic Ni-azide chain and compound II has Cu6 azide units forming a column terminated by the copper-metalloligand generated in-situ during the course of the reaction. The charge compensation perchlorate anions occupy spaces in between the chains in I. Compound II packs in a herringbone arrangement, which is not commonly observed in low-dimensional structures. Compound III has one-dimensional copper-azide chains connected through copper-metalloligand forming the two-dimensional structure. All the three compounds exhibit anti-ferromagnetic behavior. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF
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