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1

Bond-valence Approach to the Semicoordination in Seven-Coorinated Copper(II) Complexes with 4-Aminopyridine: Crystal and MOlecular Structure of Bis(4-aminopyridine)di(acetato)(aqua)copper(II)

100%

Grobelny R. , Valach F. , Głowiak T. , Mroziński J.

Polish Journal of Chemistry

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2005

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tom Vol. 79 / nr 1

31-36

EN

The structure of [Cu(CH3COO)2(4-aminopyridine)2(H2O)] was X-ray studied. Heptacoordinated copper atoms of [Cu(CH3COO)2(4-aminopyridine)2(H2O)] complex are consistent with bond valence sum model based on orbital metal-ligand interaction. Equatorial plane of deformed tetragonal bipyramid as copper coordination polyhedron is formed by atoms O of carboxylato ligands and water molecule. Two N atoms of 4-aminopyridine molecules occupy the axial sites. Each copper atom is semicoordinated by two atoms O from two carboxylato chelates. The lengths of two semicoordinated Cu...O bonds are 3.041(2)A (twice). Seven-coordinated copper atom of the studied compound and Cu(oxalato)(H2O) (4-aminopyridine)2 is consistent with the bond valence sum model.

2

Crystal Structure and Magnetic Properties of Copper(II) Macrocyclic Compounds

100%

Bieńko A. , Mroziński J. , Korybut-Daszkiewicz B. , Kruszyński R.

Polish Journal of Chemistry

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2008

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tom Vol. 82, nr 7

1383-1383

EN

The two higly unsaturated copper(II) macrocyclic complexes [CuL1](ClO4)2 (1) (L1 = N-dl-5,12-dimethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene) and [CuL2](ClO4)2 (2) (L2 = N-dl-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-4,11-diene) were synthesized and the crystal structures of both compounds were determined at 173(2) K. Complex 1 crystallizes monoclinic, space group P21/c, with a = 9.0929(5) Capital A, ring, b = 13.4683(5) Capital A, ring , c = 8.2886(4) ,Capital A, ring beta = 109.469(6)°, Z = 2, whereas 2 crystallizes at the same space group with a = 10.4891(2) Capital A, ring, b = 16.9924(4) Capital A, ring , c = 13.8780(3) Capital A, ring , beta = 105.150(2)° and Z = 4. Their magnetic measurements have been carried out over the temperature range 1.8–300 K using a Quantum Design SQUID magnetometer (MPMSXL - 5 type). The results indicate that both compounds be have as weakly interacting copper centers in the crystal lattice.

3

X-ray crystallographic and spectroscopic investigations of copper(II) nitrate-1-allylimidazole complexes

88%

Kurdziel K. , Głowiak T.

Polish Journal of Chemistry

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1998

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tom Vol. 72, nr 9

2181-2188

EN

Copper(II) complexes Cu2L4(NO3)4 (a) and (CuL4(NO3)2 (b), where L is 1-allylimidazole, have been synthesized and characterized by elemental analysis, IR, FTIR, near IR, VIS, magnetic and crystallographic measurements. In centrosymmetric binuclear complex (a) the nitrate anions are linked to the Cu(II) cations through bidentate oxygen atoms. In complexes (b) the Cu(II) cation occupies a symmetry centre and is tetragonalbipyramid coordinated.

4

Styrene oxidation by copper(II) complexes salen-type encapsulated into NaY zeolite

75%

Kuźniarska-Biernacka I. , Carvalho M. A. , Correia Neves I. , Fonseca A. M. , Lisińska-Czekaj A. , Czekaj D.

Archives of Metallurgy and Materials

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2013

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tom Vol. 58, iss. 4

1291--1294

EN

The copper(II) complex with a Schiff-base salen-type ligand has been encapsulated in the nanopores of a NaY zeolite by using two different methodologies, the flexible ligand and in situ complex preparation methods. The encapsulated and non-encapsulated copper(II) complexes were screened as catalysts for styrene oxidation by using TBHP as the oxygen source in acetonitrile solvent. Under the optimized conditions, the catalysts exhibited moderate activity with higher selectivity to benzaldehyde. Both heterogeneous catalysts were found to be reusable after the catalytic cycle, but with some loss of activity.

PL

Osadzenie kompleksu miedzi(II) z zasadą Schiffa typu salen na zeolicie typu NaY zostało przepowadzone za pomocą dwóch metod „flexible ligand" i „in situ”. Katalityczne właściwości otrzymanego kompleksu oraz jego heterogenizowanych analogów badano w reakcji utleniania styrenu w obecności TBHP. Jako rozpuszczalnik stosowano acetonitryl. Testowane katalizatory wykazują średnią aktywność katalityczną z tendencją wytwarzania aldehy du benzoesowego. Oba heterogenizowane katalizatory mogą być wykorzystywane ponownie bez utraty aktywności katalitycznych.

5

Determination of Stability Constans of Copper(II)/Cobalt(II)-Methionine and Copper(II)/Cobalt(II)-Methionine-Cysteine (Binary and Mixed) Complexes by Paper Electrophoretic Technique

75%

Tewari B.

Polish Journal of Chemistry

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2005

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tom Vol. 79 / nr 12

1853-1860

EN

The stability constants of copper(II) and cobalt(II) with methionine and cysteinewere determined by paper ionophoretic technique. Beside binary, mixed ligand complexes have also been studied, in which methionine and cysteine act as primary and secondary ligand, respectively. The stability constant of Cu(II)-methionine-cysteine and Co(II)-methionine-cysteine mixed ligand complexes were found to be 2.80+ -0.07 and 2.44+ -0.11 (logarithm of stability constant values), respectively at ionic strength 0.1 M and temperature of 35 graduate C.

6

New Polymeric Copper(II) Complexes with Tributy I Phosphite and Perfluorinated Carboxylates

63%

Szłyk E. , Szymańska I. , Kucharek R. , Wrzeszcz G. , Rozpłoch F.

Polish Journal of Chemistry

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2001

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tom Vol. 75, nr 2

215-222

EN

New Cu(II) complexes with tributyl phosphite and aliphatic perfluorinated carboxylates [Cu{P(OBu)3}(ž-OH)(ž-RCOO)]n, where R = CF3, C2F5, C3F7, C6F13, C7F15, were obtained and their spectroscopic (UV-VIS, EPR, MS, IR) and thermal properties were studied. Mass spectra were in favour of the bridging coordination carboxylates and monodentate phosphite and suggest a polymeric structure. EPR spectra and magnetic susceptibility measurements indicate the formation of pentacoordinated Cu(II) in polymeric complexes. Examination of COO absorption bands suggests bridging carboxylates as well as a hydroxo group, whereas tributyl phosphite is monodentately bonded. Thermal decomposition is a multistage process, which in nitrogen and air yields a mixture of Cu2O and Cu2P2O7.

7

Białka błony zewnętrznej fusobacterium nucleatum jako potencjalny czynnik promocji nowotworu jelita grubego

63%

Lesiów M. K. , Krupa K. , Komarnicka U. K. , Walencik P. K.

Wiadomości Chemiczne

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2018

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tom [Z] 72, 7-8

585--596

EN

Fusobacterium nucleatum is a Gram-negative, anaerobic bacterium located in an oral cavity. This bacterium can migrate with blood to the different part of the human body e.g colon. The studies suggest participation of Fn in a colorectal cancer promotion, but a particular mechanism of this disease is still unclear. Colorectal cancer leads to million of new death cases each year. It is third in the worldwide in terms of mortality. The predictions for the coming years are not optimistic. The statistics encourage researchers to know the details of the mechanism of colorectal cancer. It is suggest, that outer membrane proteins of Fn are responsible for development of this disease. Transition metal ions such as Cu(I), Cu(II), Fe(II) can coordinate to proteins and generate free radicals by Fenton reaction. Reactive oxygen species (ROS) destroy important biological macromolecules such as DNA, proteins or lipids and cause different diseases. The paper presents characteristics of Fn and its outer membrane proteins, description of copper(II) complexes and their ability to ROS generation.

8

Synthesis and characterization of diantipyrylmethanium salts of some pseudo-tetrahedral anionic copper(II) complexes

63%

Wrzeszcz G. , Grodzicki A. , Pawlak R. , Rozpłoch F.

Polish Journal of Chemistry

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1998

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tom Vol. 72, nr 10

2232-2241

EN

The tetrachlorocuprate(II), tetrabromocuprate(II) and tetrakis(izothiocyanate)cuprate(II) complexes of diantipyrylmethanium cations have been prepared and formulated as (H2DAM)CuCl4, (H2DAM)CuBr4, and (HDAM)2Cu(NCS)4 on the basis of spectral data (IR, UV-VIS) and elemental analysis. The EPR spectra, variable temperature magnetic susceptibility and thermal properties in air have been investigated. The results indicate for all complexes a distored tetrahedral configuration. All studied complexes exhibited Curie-Weiss behaviour between 80-300 K. Thermal decomposition is a multistage process and yields CuO as final product.

9

Vibrational spectra, electronic excited states and magnetic properties of the copper(II) ions in alkylaminoacetylurea complexes

63%

Ciurla H. , Hanuza J. , Talik Z. , Korabik M. , Mrozinski J.

Materials Science Poland

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2009

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tom Vol. 27, No. 1

5--21

EN

Copper(II) complexes with alkylaminoacetylurea ligands were synthesized and studied by means of IR, Raman, electron absorption and luminescence spectroscopies, as well as by ESR and magnetic methods. The spectroscopic and magnetic studies were performed in the 4-300 K and 1.9-300 K temperature ranges, respectively. The Cu2+ ions in these complexes are four coordinated having distorted squareplanar surroundings. The dependence of the spectroscopic parameters on the alkyl radical of the ligand is discussed. At low temperatures, very weak ferromagnetic interactions are observed for the C3 and C5 alkyls, and an antiferromagnetic one is observed for the remaining complexes, with C4 and C6-C18 alkyls.

10

Magnetyczne oddziaływania nadwymienne przez wiązania wodorowe

63%

Korabik M.

Wiadomości Chemiczne

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2008

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tom [Z] 62, 5-6

449-478

EN

Hydrogen bonds play a key role in interactions in biological structures, supramolecular chemistry, and crystal engineering [28, 29]. The development of supramolecular structure created by hydrogen bonds is a new challenge for the synthesis of materials, in order to study their magnetic behaviour [59, 62]. A role played by hydrogen bonds in the transmission of magnetic interactions is still not fully understood, but the number of magnetically coupled hydrogen-bonded systems is growing. The present paper describes magnetic properties of copper(II) complexes [33] with nitrobenzoate and salicylate ligands where the system of hydrogen bonds O-HźźźO is the only path of magnetic interaction. Magnetic measurements in the temperature range 1.8-300 K show magnetic phase-transition at 6 K to antiferromagnetically coupled CuII dimers with singlet-tryplet energy gap 2J = -6.26 cm-1. A variety of different supramolecular hydrogen bond structures [27, 33-52, 57-62] and significant changes in their magnetic properties were analyzed to show the role of hydrogen bonds in magnetic interactions. Magnetostructural correlation has been made taking into account both covalently bridging ligand and the existence of intermolecular hydrogen bonds. An evidence for hydrogen-bond-mediated exchange coupling has been observed in magnetic study as well as in DFT calculations [40, 48]. Intermolecular interaction has been generally treated as a nuance, but today, it has established itself as an important functional tool, tunable at will [59] in the design of nanosized magnetic materials and their dimensionally-expanded compounds [57-62]. Intermolecular magnetic exchange interactions through hydrogen bonds, can have a large influence on the quantum properties of single molecular magnets SMMs [59]. Hydrogen bonding leads to coupling of the magnetic effects of individual SMMs units and to different quantum behaviour. Even very weak hydrogen bond inter-molecular interactions demonstrate a possibility of switching from an original nanosized magnetic system to a correlated system, for example, from single molecule magnet SMM to single chain magnet SCM or from such nanosized magnets to a bulk magnet [59].

11

Właściwości antyoksydacyjne, antybakteryjne i przeciwgrzybicze związków kompleksowych miedzi(II)

63%

Piotrowska A. , Drzeżdżon J. , Jacewicz D. , Chmurzyński L.

Wiadomości Chemiczne

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2017

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tom [Z] 71, 3-4

219--240

EN

Since late 1930s copper has been recognized as an essential trace metal in living organisms. Copper(II) cation plays the role as a coordination center not only in the single-nuclear complexes, but also in the multinuclear coordination compounds with a particular emphasis on the polymers as ligands. The selected complex compounds of copper(II) with ligands which are organic and inorganic species have been characterized taking into account their physico-chemical properties. In addition, the complex compounds containing ligands such as Schiff ’s bases, hydrocarbons, organic bases, and also polycarboxylic anions: oxydiacetate, thiodiacetate, iminodiacetate and dipicolinate have been described considering their role in the biological systems. Nowadays tested coordination compounds of copper(II) have interesting antibacterial activities against bacteria strains that are antagonistic to the human. The antibacterial activity of copper(II) complex is stronger than some of the known antibacterial substances e.g. ciprofloxacin. In addition, copper(II) complex compounds exhibit a 64-fold greater antimicrobial properties than copper(II) chloride. Moreover, these compounds have antifungal and antioxidant properties. The activities of antibacterial, antifungal, and antioxidant complex compounds of copper( II) have been compared to the reactivities of these compounds with complexes used as reference substances, e.g. L-ascorbic acid, in the assay using nitrotetrazolium blue.

12

Ability of 2,4D and 2,4DP Herbicides to Combine with Metal Ions of Biological Interest (Part 1): Copper(II) Complexes

51%

Zwolińska A. , Ptaszyński B. , Wrzeszcz G.

Polish Journal of Chemistry

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2004

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tom Vol.78 /nr 11-12

1987-1996

EN

Copper(II) complexes with the commercial auxin herbicides 2,4-dichlorophenoxyacetic acid (2,4D; C8H6O3Cl2) and 2-(2,4-dichlorophenoxy)-propionic acid (2,4DP;C9H8O3Cl2) were prepared and characterized. On the basis of the results of elemental analysis and Cu(II) determination, the following molecular formulae were proposed for the obtained compounds: Cu(C8H5O3Cl2)2.4H2O (Cu-2,4D) and Cu(C9H7O3Cl2)2.H2O (Cu-2,4DP).Water solubility of synthesized complexes at room temperature was determined. The complexes have been characterized by IR, VIS and EPR spectroscopy, conductivity (in methanol and dimethyloformamide), magnetic measurements and X-ray diffraction analysis. Thermal decomposition of these compounds in air was studied by TG, DTG, DTAand TG/MS methods with simultaneous analysis of the solid and gaseous products.