Artigos de revistas: "Cobalt compounds"

1

Thomas, Nicholas C., Katrina Pringle e Glen B. Deacon. "Cobalt(II) and cobalt(III) coordination compounds". Journal of Chemical Education 66, n.º 6 (junho de 1989): 516. http://dx.doi.org/10.1021/ed066p516.

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Ávila-Torres, Yenny, Lázaro Huerta e Noráh Barba-Behrens. "XPS-Characterization of Heterometallic Coordination Compounds with Optically Active Ligands". Journal of Chemistry 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/370637.

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The heterometallic optical complexes [Cu2Co(S,S(+)cpse)3(H2O)3]·4H2O (1) and [Cu2Ni(S,S(+)cpse)3(H2O)3]·10H2O (2) were obtained from the mononuclear copper(II) compound by the addition of nickel(II) or cobalt(II) chlorides, where (H2cpse) is the acetyl amino alcohol derivative N-[2-hydroxy-1(R)-methyl-2(R)-phenylethyl]-N-methylglycine. In comparison with the homotrinuclear copper(II) compound [Cu3(S,S(+)cpse)3(H2O)3]·8H2O reported previously, the substitution of a copper(II) atom by one cobalt(II) ion gave place to a heterotrinuclear compound1, which presents ferromagnetic-antiferromagnetic behaviour. When substituting a copper(II) by a nickel(II) ion, the trinuclear compound2showed an antiferromagnetic coupling. The magnetic behaviour of the heterotrinuclear compounds is driven by the nature of the metal ion which was introduced in the copper(II) triangular array. The ligand and its coordination compounds were characterized by IR, UV-Vis-NIR. Their chemical was confirmed by photoelectron spectroscopy (XPS).

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Tang, Yao, Zhao Lin Zhan, Xiao Hua Yu, Miao Ma e Xiao Yu Li. "Development and Application of Manganese Cobalt Lithium Compounds in the Field of Lithium Batteries". Advanced Materials Research 1088 (fevereiro de 2015): 275–78. http://dx.doi.org/10.4028/www.scientific.net/amr.1088.275.

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Manganese lithium cobalt compounds have been used in the preparation of lithium battery cathode material because of its excellent electrochemical characteristics and gradually in recent years. This paper introduces the different methods of preparing the compounds, analyzes the structural characteristics of the manganese cobalt lithium compounds and the differences in the electrochemical properties, the end of the article has carried on the forecast to the future development direction of the compound.

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Djordjevic, Milena, Dejan Jeremic, Katarina Andjelkovic, Maja Gruden-Pavlovic, Vladimir Divjakovic, Maja Sumar-Ristovic e Ilija Brceski. "Cobalt(II) and cadmium(II) compounds with adamantane-1-sulfonic acid". Journal of the Serbian Chemical Society 77, n.º 10 (2012): 1391–99. http://dx.doi.org/10.2298/jsc120419051d.

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In this work we reported syntheses and characterization of two novel compounds of adamantane-1-sulfonic acid (1-AdSO3H) with cobalt(II) and cadmium(II), respectively. The result of the single crystal X-ray analysis of compounds revealed that adamantane-1-sulfonate (1-AdSO3 -) in monoanionic form plays a different role in investigated compounds. Namely, while in compound [Co(H2O)6](1-AdSO3)2 six water molecules are coordinated to cobalt(II) ion and 1-AdSO3 - serves as a counter ion, in compound [Cd(H2O)4(1-AdSO3)2] two molecules of 1-AdSO3 - are trans-coordinated to the cadmium(II) ion as monodentate (O) ligand and other coordination sites are occupied by water molecules. The obtained compounds showed a moderate activity against Artemia salina.

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Gluhcheva, Yordanka, Vasil Atanasov, Juliana Ivanova e Ekaterina Pavlova. "Chronic exposure to cobalt compounds — an in vivo study". Open Life Sciences 9, n.º 10 (1 de outubro de 2014): 973–81. http://dx.doi.org/10.2478/s11535-014-0334-x.

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AbstractAn in vivo experimental model for testing the effects of long-term chronic treatment with cobalt(II) compounds — cobalt chloride (CoCl2) and cobalt-EDTA (Co-EDTA) on mice at different stages of development was optimized. Pregnant mice and their progeny were treated with daily doses of 75 or 125 mg kg−1 body weight until postnatal day 90. The compounds were dissolved in regular tap water. Mice were sacrificed on days 18, 25, 30, 45, 60 and 90 after birth, which correspond to different stages of their development. Altered organ weight indices (calculated as a ratio of organ weight to body weight) of spleen, liver and kidneys, were found depending on the type of compound used, dose, duration of treatment, and the age of the animals. The results also showed significant accumulation of cobalt ions in blood plasma, spleen, liver and kidneys of the exposed mice. More Co(II) was measured in the organs of the immature mice (day 18, 25 and 30 pnd) indicating that they were more sensitive to treatment.

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Ishikawa, T., e E. Matijević. "Formation of uniform particles of cobalt compounds and cobalt". Colloid & Polymer Science 269, n.º 2 (fevereiro de 1991): 179–86. http://dx.doi.org/10.1007/bf00660309.

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Stopford, Woodhall, John Turner, Danielle Cappellini e Tom Brock. "Bioaccessibility testing of cobalt compounds". Journal of Environmental Monitoring 5, n.º 4 (2003): 675. http://dx.doi.org/10.1039/b302257a.

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Filipczyk, Grzegorz, Steve W. Lehrich, Alexander Hildebrandt, Tobias Rüffer, Dieter Schaarschmidt, Marcus Korb e Heinrich Lang. "Multiferrocenyl Cobalt-Based Sandwich Compounds". European Journal of Inorganic Chemistry 2017, n.º 2 (5 de outubro de 2016): 263–75. http://dx.doi.org/10.1002/ejic.201600848.

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Harwell, David E., Juliet Nabakka, Carolyn B. Knobler e M. Frederick Hawthorne. "Synthesis and structural characterization of an ether-bridged cobalta-bis(dicarbollide): a model for Venus flytrap cluster reagents". Canadian Journal of Chemistry 73, n.º 7 (1 de julho de 1995): 1044–49. http://dx.doi.org/10.1139/v95-129.

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The synthesis of bis-(1-carboranylmethyl) ether was first published in 1963; however, its subsequent complexation with a transition metal was never reported. We now report the complexation of cobalt and the corresponding X-ray structure for the triphenylmethylphosphonium salt of the cobalta-bis(carboranylmethyl) ether. The cobalt complex crystallized in the monoclinic space group C2/c with a = 21.729(6) Å, b = 9.845(2) Å, c = 35.565(9) Å, β = 105.363(9)°, V = 7336 Å3, and Z = 8. Data were collected using CuKα radiation, to a maximum 2θ = 115°, giving 4123 unique reflections, and the structure was solved by heavy atom methods. The final discrepancy index was R = 0.093, Rw = 0.100 for 1919 independent reflections with I > 3σ(I). This metala-bis(carboranylalkyl) ether is the first in a new class of Venus flytrap compounds (VFC), containing an ether linkage, to be synthesized as model compounds for the development of reagents suitable for use in the radioimmunodetection and radioimmunotherapy of cancer. Keywords: cobalt, radioimmunodetection, radioimmunotherapy, Venus flytrap.

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10

Krebs, Christoph, Inke Jess, Magdalena Ceglarska e Christian Näther. "Crystal structure of diethanolbis(thiocyanato)bis(urotropine)cobalt(II) and tetraethanolbis(thiocyanato)cobalt(II)–urotropine (1/2)". Acta Crystallographica Section E Crystallographic Communications 78, n.º 1 (1 de janeiro de 2022): 66–70. http://dx.doi.org/10.1107/s2056989021013281.

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The reaction of one equivalent Co(NCS)2 with four equivalents of urotropine (hexamethylenetetramine) in ethanol leads to the formation of two compounds, namely, bis(ethanol-κO)bis(thiocyanato-κN)bis(urotropine-κN)cobalt(II), [Co(NCS)2(C6H12N4)2(C2H6O)2] (1), and tetrakis(ethanol-κO)bis(thiocyanato-κN)cobalt(II)–urotropine (1/2), [Co(NCS)2(C2H6O)4]·2C6H12N4 (2). In 1, the Co cations are located on centers of inversion and are sixfold coordinated by two terminal N-bonded thiocyanate anions, two ethanol and two urotropine ligands whereas in 2 the cobalt cations occupy position Wyckoff position c and are sixfold coordinated by two anionic ligands and four ethanol ligands. Compound 2 contains two additional urotropine solvate molecules per formula unit, which are hydrogen bonded to the complexes. In both compounds, the building blocks are connected via intermolecular O—H...N (1 and 2) and C—H...S (1) hydrogen bonding to form three-dimensional networks.

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Léonard, A., e R. Lauwerys. "Mutagenicity, carcinogenicity and teratogenicity of cobalt metal and cobalt compounds". Mutation Research/Reviews in Genetic Toxicology 239, n.º 1 (julho de 1990): 17–27. http://dx.doi.org/10.1016/0165-1110(90)90029-b.

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Olazabal, Claudia A., Francois P. Gabbai, Alan H. Cowley, Carl J. Carrano, Ladd M. Mokry e Marcus R. Bond. "Intramolecular Base Stabilization of Cobalt-Gallium and Cobalt-Indium Compounds". Organometallics 13, n.º 2 (fevereiro de 1994): 421–23. http://dx.doi.org/10.1021/om00014a008.

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13

Reutskyy, Viktor, Oleksandr Ivashchuk, Sergiy Mudryy e Nataliya Mitina. "Cyclohexane Oxidation in the Presence of Cobalt Chelates". Chemistry & Chemical Technology 4, n.º 4 (15 de dezembro de 2010): 261–64. http://dx.doi.org/10.23939/chcht04.04.261.

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14

Pham, Duyen N. K., Mrittika Roy, Ava Kreider-Mueller, James A. Golen e David R. Manke. "The crystal structures of iron and cobalt pyridine (py)–sulfates, [Fe(SO4)(py)4] n and [Co3(SO4)3(py)11] n". Acta Crystallographica Section E Crystallographic Communications 74, n.º 6 (31 de maio de 2018): 857–61. http://dx.doi.org/10.1107/s2056989018007557.

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The solid-state structures of two metal–pyridine–sulfate compounds, namely catena-poly[[tetrakis(pyridine-κN)iron(II)]-μ-sulfato-κ2 O:O′], [Fe(SO4)(C5H5N)4] n , (1), and catena-poly[[tetrakis(pyridine-κN)cobalt(II)]-μ-sulfato-κ2 O:O′-[tetrakis(pyridine-κN)cobalt(II)]-μ-sulfato-κ3 O,O′:O′′-[tris(pyridine-κN)cobalt(II)]-μ-sulfato-κ2 O:O′], [Co3(SO4)3(C5H5N)11] n , (2), are reported. The iron compound (1) displays a polymeric structure, with infinite chains of FeII atoms adopting octahedral N4O2 coordination environments that involve four pyridine ligands and two bridging sulfate ligands. The cobalt compound (2) displays a polymeric structure, with infinite chains of CoII atoms. Two of the three Co centers have an octahedral N4O2 coordination environment that involves four pyridine ligands and two bridging sulfate ligands. The third Co center has an octahedral N3O3 coordination environment that involves three pyridine ligands, and two bridging sulfate ligands with one sulfate chelating the cobalt atom.

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15

Tupolova, Yulia P., Denis V. Korchagin, Anastasya S. Andreeva, Valery V. Tkachev, Gennadii V. Shilov, Vladimir A. Lazarenko, Leonid D. Popov et al. "Mononuclear Heptacoordinated 3d-Metal Helicates as a New Family of Single Ion Magnets". Magnetochemistry 8, n.º 11 (9 de novembro de 2022): 153. http://dx.doi.org/10.3390/magnetochemistry8110153.

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The series of Co(II), Fe(II), and Ni(II) mononuclear coordination compounds of [CoL(NCS)2]·3DMSO (1), [CoL(H2O)2](ClO4)2·DMSO (2), [CoL(H2O)(EtOH)][CoCl4]·2H2O (2a), [FeL(NCS)2]·DMSO (3), and [NiL(NCS)2]·CH3CN (4) composition (where L is 2,6-bis(1-(2-(4,6-dimethylpyrimidin-2-yl)hydrazineylidene)ethyl)pyridine), with an [MLA2] coordination unit (where A is a pair of apical monodentate ligands), was synthesized. In compounds 1, 2, 2a, and 3, the ligand L is pentadentate, and cobalt and iron ions are placed in a heavily distorted pentagonal pyramidal coordination environment, while in 4 the Ni(II) ion is hexacoordinated. Easy plane-type magnetic anisotropy (D = 13.69, 11.46, 19.5, and 6.2 cm−1 for 1, 2, 2a, and 4, respectively) was established for cobalt and nickel compounds, while easy axis-type magnetic anisotropy (D = −14.5 cm−1) was established for iron compound 3. The cobalt coordination compounds 1 and 2 show SIM behavior under a 1500 Oe external magnetic field, with effective magnetization reversal barriers of 65(1) and 60(1) K for 1 and 2, respectively. The combination of Orbach and Raman relaxation mechanisms was shown to adequately describe the temperature dependence of relaxation times for 1 and 2. CASSCF/NEVPT2 calculations were performed to model the parameters of the effective spin Hamiltonian for the compounds under study.

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Namdeo, Pratibha, Arpan Bhardwaj e S. K. Verma. "SYNTHESIS OF MIXED LIGAND METAL COMPLEX OF CU (II) WITH SCHIFF BASE AND THIOACETAMIDE". International Journal of Engineering Technologies and Management Research 4, n.º 12 (23 de abril de 2020): 24–26. http://dx.doi.org/10.29121/ijetmr.v4.i12.2017.587.

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Complex compounds were identified in the 19th century. The formation of hexammine cobalt(III) chloride [CO (NH3)6] Cl3 which is prepared from cobalt chloride and ammonia is thefirst compound, studied and real beginning of coordination Chemistry [1]. Alfred Werner firstexplained the nature of bonding and structure of these complexes and he was awarded NoblePrize in 1913 [2]. He gave the concept of primary (ionisable) valency and secondary(unionsible) valencies of metal ion.

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Danzeisen, Ruth, David Lee Williams, Vanessa Viegas, Michael Dourson, Steven Verberckmoes e Arne Burzlaff. "Bioelution, Bioavailability, and Toxicity of Cobalt Compounds Correlate". Toxicological Sciences 174, n.º 2 (14 de fevereiro de 2020): 311–25. http://dx.doi.org/10.1093/toxsci/kfz249.

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Abstract Based on the wide use of cobalt substances in a range of important technologies, it has become important to predict the toxicological properties of new or lesser-studied substances as accurately as possible. We studied a group of 6 cobalt substances with inorganic ligands, which were tested for their bioaccessibility (surrogate measure of bioavailability) through in vitro bioelution in simulated gastric and intestinal fluids. Representatives of the group also underwent in vivo blood kinetics and mass balance tests, and both oral acute and repeated dose toxicity (RDT) testing. We were able to show a good correlation between high in vitro bioaccessibility with high in vivo bioavailability and subsequent high in vivo toxicity; consequently, low in vitro bioaccessibility correlated well with low in vivo bioavailability and low in vivo toxicity. In vitro bioelution in simulated gastric fluid was the most precise predictor of the difference in the oral RDT lowest observed adverse effect levels of 2 compounds representing the highly and poorly bioaccessible subset of substances. The 2 compounds cobalt dichloride hexahydrate and tricobalt tetraoxide differed by a factor of 440 in their in vitro bioaccessibility and by a factor of 310 in their RDT lowest observed adverse effect level. In summary, this set of studies shows that solubility, specifically in vitro bioelution in simulated gastric fluid, is a good, yet conservative, predictor of in vivo bioavailability and oral systemic toxicity of inorganic cobalt substances. Bioelution data are therefore an invaluable tool for grouping and read across of cobalt substances for hazard and risk assessment.

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Sibirkina, Alfira Raviljevna, e Sergej Fedorovich Likhachev. "Comparison of cobalt compounds content in organs and tissues of woody plants". Samara Journal of Science 6, n.º 2 (1 de junho de 2017): 84–87. http://dx.doi.org/10.17816/snv201762116.

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The paper presents results of a comparative analysis of cobalt compounds content in the organs and tissues of woody plants in pine forests of the Semipalatinsk Irtysh Republic of Kazakhstan. The investigated forests belong to the dry-steppe area of the Irtysh ribbon belt on the sands of the Irtysh and the provinces of the Priirtyshsky belt in the valleys of the ancient runoff. The investigated area of borons is characterized by a simple stand, formed by trees of approximately one height (20-25 m). The fluctuations between the heights of individual trees do not exceed 10-15%. Scots pine ( Pinus sylvestris L.) is a species - edificator. Aspen ( Populus tremula L.) and birch pendant ( Betula pendula Roth.) are trees of the second size. They appeared after fires and intensive deforestation as a result of secondary succession. Particular attention was paid to needles during the analysis. Needles perform an assimilating function and determine the growth and development of other organs. The determination of cobalt compounds was carried out at the Institute of Geology and Mineralogy (IGM SB RAS) (Novosibirsk) using atomic absorption spectroscopy methods. The calculation of the biogeochemical cycle of the stand was carried out. The mass of cobalt compounds involved in the biogeochemical cycle with the total phytomass of the stand was 0,0090 t / ha, and the phytomass of the aboveground part of the tree was 0,0087 t / ha. The state of the stand according to the Kraft classification corresponds to the I-III class of vitality, depending on the site of occurrence. The stand of boron is characterized by high capacity of biological absorption of cobalt compounds. A comparative analysis of the accumulation of cobalt compounds by different types of trees was carried out. Leaves and branches of deciduous trees are characterized by the maximum accumulation of cobalt compounds in comparison with pine needles and Pinus sylvestris L. The leaves of Populus tremula L. accumulate more cobalt compounds than leaves of Betula pendula Roth. According to the series of biological absorption, cobalt is an element of strong accumulation for woody plants, based on the potential biogeochemical mobility of metals. Cobalt does not play an important role in the general circulation of substances in the forest ecosystem, based on the biotic index.

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Jiang, Feng, Maxime A. Siegler, Xiaobo Sun, Lin Jiang, Célia Fonseca Guerra e Elisabeth Bouwman. "Redox Interconversion between Cobalt(III) Thiolate and Cobalt(II) Disulfide Compounds". Inorganic Chemistry 57, n.º 15 (19 de julho de 2018): 8796–805. http://dx.doi.org/10.1021/acs.inorgchem.8b00549.

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Jameh-Bozorghi, Saeed, Zahra Javanshir e D. Nori Shargh. "Prototropic and metallotropic migration of isolobal fragments on indol rings. Theoretical study and NBO analysis". JOURNAL OF ADVANCES IN CHEMISTRY 5, n.º 1 (29 de abril de 2009): 614–25. http://dx.doi.org/10.24297/jac.v5i1.942.

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Molecular structures, energies, NBO analysis and sigmatropic behaviour of 1-Indenyl(dihydro)borane (1) and 1-Indenyl-threecarbonylcobalt(I) (2) were investigated using DFT and ab initio molecular orbital methods. In these compounds BH2 and Co(CO)3 fragments areisolobal. The Results of calculations using B3LYP, HF and MP2methods [Basis set 6-311+G**] showed that -BH2 and -Co(CO)3 had similar behaviour in sigmatropic shifts. Prototropic shifts in compounds 1 and 2 have similar mechanisms too. Results showed that metallotrotropic shift is faster than Prototrpic shift in compounds 1 and 2. The activation energies (Ea) of Prototropic shift in compounds 1 and 2 are 18.83 and 17.38 kcal.mol-1. These energies are higher than -BH2 shifts in compound 1 (10.11 kcal.mol-1) or migration of -Co(CO)3 fragment in compound 2 (12.39 kcal.mol-1). Lower amount of activation energy in borotropic shift and cobalt`s fragment shift show that rotation of boron and cobalt on the indol ring can happen in the ambient temperature. Calculation results revealed that migration of proton and Co(CO)3 was carried out via suprafacial[1,2]-sigmatropic mechanism while -BH2 shift took place via antrafacial [1,3]-rearangment.

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Kowalski, Grzegorz, Jan Pielichowski e Mirosław Grzesik. "Characteristics of Polyaniline Cobalt Supported Catalysts for Epoxidation Reactions". Scientific World Journal 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/648949.

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A study of polyaniline (PANI) doping with various cobalt compounds, that is, cobalt(II) chloride, cobalt(II) acetate, and cobalt(II) salen, is presented. The catalysts were prepared by depositing cobalt compounds onto the polymer surface. PANI powders containing cobalt ions were obtained by one- or two-step method suspending PANI in the following acetonitrile/acetic acid solution or acetonitrile and then acetic acid solution. Moreover different ratios of Co(II) : PANI were studied. Catalysts obtained with both methods and at all ratios were investigated using various techniques including AAS and XPS spectroscopy. The optimum conditions for preparation of PANI/Co catalysts were established. Catalytic activity of polyaniline cobalt(II) supported catalysts was tested in dec-1-ene epoxidation with molecular oxygen at room temperature. The relationship between the amount of cobalt species, measured with both AAS and XPS techniques, and the activity of PANI-Co catalysts has been established.

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Neamah, S. I. "INDUCING SOME SECONDARY METABOLITES FROM CALLUS CULTURES DERIVED FROM Plantago psyllium AND Plantago major EXPOSED TO COBALT STRESS". IRAQI JOURNAL OF AGRICULTURAL SCIENCES 51, n.º 3 (26 de junho de 2020): 938–43. http://dx.doi.org/10.36103/ijas.v51i3.1049.

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This experiment was conducted to study the influence of cobalt concentrations on the production of seven flavonoid compounds in callus derived from Plantago psyllium L. and Plantago major L. Results showed that the best combination of 2,4-D and kinetin concentrations add to Muroshige and Skoog medium to obtain the highest fresh weight of 541.0 mg was 3.0 and 1.0 mg.L-1 respectively. psyllium stimulated callus produced the highest fresh weight of 365.7 mg. The addition of 75 ppm of cobalt resulted in a significantly lower fresh weight of P. psyllium callus (139.8 mg). The interaction between Plantago species and cobalt concentrations was significant. The callus inducted from P. major had significant increases of the scutallarein, apigenin, nepetin and luteolin compounds with 26.40, 22.64, 14.93 and 26.20 µg.100mg-1 dry weight, respectively. The production of the hispidulin compound was increased in P. psyllium at 29.40 µg.100mg-1 dry weight. Also, the addition of cobalt metal stimulated the production of flavonoids at 50 ppm cobalt producing the highest amounts of hispidulin and luteolin at 40.30 and 41.60 µg.100mg-1 dry weight, respectively. Meanwhile, 75 ppm cobalt treatment produced the highest amount of scutallarein, apigenin, nepetin and aucubin at 25.61, 23.25, 15.90 and 13.70 µg.100mg-1 dry weight, respectively. The callus inducted from P. major treated with 50 ppm of cobalt showed the highest production of scutallarein, apigenin and luteolin at 30.33, 32.26 and 51.90 µg.100mg-1 dry weight respectively. Baicalein reached 16.46 µg.100mg-1 dry weight, at 75 ppm of cobalt metal treatment in callus inducted from P. psyllium.

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Zozulia, V., J. Shatrava, T. Sliva, V. Ovchynnikov e V. Amirkhanov. "COORDINATION COMPOUNDS OF COBALT AND COPPER BASED ON CAPH LIGAND N,N'-DIBENZYL-N"-TRICHLORACETYLPHOSPHORIC TRIAMIDE". Bulletin of Taras Shevchenko National University of Kyiv. Chemistry, n.º 1(55) (2018): 27–31. http://dx.doi.org/10.17721/1728-2209.2018.1(55).6.

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Сarbacylamidophosphates is a class of organic compounds having a composition -C(O)NHP(O)=. The presence of both peptide and phosphoramidic groups in the same molecule causes a wide range of inherent biological properties. On the basis of the ligand of the carbacylamide phosphorus type (CAPh ligand) N, N'-dibenzyl-N"-trichloroacetylphosphoric triamide (HL), di- and tetramer coordination compounds were synthesized: cobalt (II) Co2L4(СH3OH)2 and copper (ІI) Cu4L4(OCH3)4. The composition and structure of the synthesized compounds was studied using the methods of IR spectroscopy, thermogravimetric and X-ray diffraction analysis. The bidentate-cyclic coordination of ligands through oxygen atoms of the phosphoryl and carbonyl groups was established on the basis of Х-ray structural analysis data. In the Co2L4(СH3OH)2 complex ionic cobalt associates together forming centroscopic dimers due to the bridging function of the phosphoryl group. The coordination sphere also includes methanol molecules, which are coordinated to the metal atom and additionally linked to the oxygen atom of the carbonyl group by hydrogen bonding, which can be considered as an additional stabilizing factor in the formation of the dimeric structure. The copper compound is a Cu4L4(OCH3)4 tetramer, in which methylate ion through µ3-bridging coordination bind four copper atoms to a tetramer. According to the thermogravimetric data, the first mass loss for the cobalt complex is observed in the range from 80°C to 150°C and corresponds to the loss of two methanol molecules. On the TGA curve, two exothermic effects are observed at temperatures of 218°C and 269°C, which are due to the process of oxidative degradation of organic ligands. Unlike the compound of cobalt, the tetramer complex of copper contains methylate ion, therefore the complex is resistant to a temperature of 110°С; with further rise in temperature there is a destruction of the organic part of this complex. The DTA curve shows an exothermic effect at a temperature of 168°C. Residues after the destruction of the complexes correspond to polyphosphates of copper and cobalt.

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Dembinski, Roman, Renata Kaczmarek, Dariusz Korczyński e Karolina Królewska-Golińska. "Organometallic Nucleosides: Synthesis and Biological Evaluation of Substituted Dicobalt Hexacarbonyl Alkynyl Modified 2′-Deoxyuridines". Proceedings 22, n.º 1 (12 de agosto de 2019): 62. http://dx.doi.org/10.3390/proceedings2019022062.

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In continuation of synthetic pursuit of metallo-nucleosides, in particular dicobalt hexacarbonyl 5-alkynyl-2′-deoxyuridines, novel compounds with alkynyl groups were synthesized, starting from 5-iodo-2′-deoxyuridine. Reactions of dicobalt octacarbonyl [Co2(CO)8] with 2′-deoxy-5-oxopropynyluridines and related compounds gave dicobalt hexacarbonyl nucleoside complexes (83–31%). The growth inhibition of HeLa and K562 cancer cell lines by organometallic nucleosides was examined and compared to that by alkynyl nucleoside precursors. Coordination of the dicobalt carbonyl moiety to the 2′-deoxy-5-alkynyluridines led to a significant increase in its cytotoxic potency. The cobalt compounds antiproliferative activities against the HeLa cell line and the K562 cell line will be described. Coordination of an acetyl-substituted cobalt nucleoside was expanded using the 1,1-bis(diphenylphosphino)methane (dppm) ligand, resulting in cytotoxicity at comparable levels. The formation of reactive oxygen species in the presence of cobalt compounds was determined in K562 cells. The results indicate that the mechanism of action for most antiproliferative cobalt compounds may be related to the induction of oxidative stress.

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Krebs, Christoph, Inke Jess e Christian Näther. "Crystal structures of two Co(NCS)₂ urotropine coordination compounds with different Co coordinations". Acta Crystallographica Section E Crystallographic Communications 78, n.º 3 (3 de fevereiro de 2022): 264–69. http://dx.doi.org/10.1107/s2056989022001037.

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The reaction of Co(NCS)2 with urotropine in ethanol leads to the formation of two different compounds, namely, bis(ethanol-κO)bis(hexamethylenetetramine-κN)bis(thiocyanato-κN)cobalt(II)–diaqua-κ 2O-bis(hexamethylenetetramine-κN)bis(thiocyanato-κN)cobalt(II)–ethanol–hexamethylenetetramine (1.2/0.8/1.6/4), [Co(NCS)2(C6H12N4)2(C2H6O)2]1.2·[Co(NCS)2(C6H12N4)2(H2O)2]0.8·1.6C2H6O·4C6H12N4, 1, and tris(ethanol-κO)(hexamethylenetetramine-κN)bis(thiocyanato-κN)cobalt(II), [Co(NCS)2(C6H12N4)(C2H6O)3], 2. In the crystal structure of compound 1, two crystallographically independent discrete complexes are observed that are located on centres of inversion. In one of them, the Co cation is octahedrally coordinated to two terminal N-bonded thiocyanate anions, two urotropine ligands and two ethanol molecules, whereas in the second complex 80% of the coordinating ethanol is exchanged by water. Formally, compound 1 is a mixture of two different complexes, i.e. diaquadithiocyanatobis(urotropine)cobalt(II) and diethanoldithiocyanatobis(urotropine)cobalt(II), that contain additional ethanol and urotropine solvate molecules leading to an overall composition of [Co(NCS)2(urotropine)2(ethanol)1.2(H2O)0.8·0.8ethanol·4urotropine. Both discrete complexes are linked by intermolecular O—H...O and O—H...N hydrogen bonding and additional urotropine solvate molecules into chains, which are further connected into layers. These layers combine into a three-dimensional network by pairs of centrosymmetric intermolecular C—H...S hydrogen bonds. In the crystal structure of compound 2, dithiocyanato(urotropine)triethanolcobalt(II), the cobalt cation is octahedrally coordinated to two terminal N-bonded thiocyanate anions, one urotropine ligand and three ethanol molecules into discrete complexes, which are located in general positions. These complexes are linked by intermolecular O—H...N hydrogen bonding into layers, which are further connected into a three-dimensional network by intermolecular C—H...S hydrogen bonding.

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Park, Ava M., Duyen N. K. Pham, James A. Golen e David R. Manke. "The varied structures of cobalt(II)–pyridine (py)–sulfate: [Co(SO4)(py)4] n , [Co2(SO4)2(py)6] n , and [Co3(SO4)3(py)11] n". Acta Crystallographica Section E Crystallographic Communications 75, n.º 12 (19 de novembro de 2019): 1888–91. http://dx.doi.org/10.1107/s205698901901538x.

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The solid-state structures of two cobalt–pyridine–sulfate compounds, namely catena-poly[[tetrakis(pyridine-κN)cobalt(II)]-μ-sulfato-κ2 O:O′], [Co(SO4)(C5H5N)4] n , (1), and catena-poly[[tetrakis(pyridine-κN)cobalt(II)]-μ-sulfato-κ3 O:O′,O′′-[bis(pyridine-κN)cobalt(II)]-μ-sulfato-κ3 O,O′:O′′] n , [Co2(SO4)2(C5H5N)6] n , (2), are reported. Compound (1) displays a polymeric structure, with infinite chains of CoII cations adopting octahedral N4O2 coordination environments that involve four pyridine ligands and two bridging sulfate ions. Compound (2) is also polymeric with infinite chains of CoII cations. The first Co center has an octahedral N4O2 coordination environment that involves four pyridine ligands and two bridging sulfate ligands. The second Co center has an octahedral N2O4 coordination environment that involves two pyridine ligands and two bridging sulfate ions that chelate the Co atom. The structure of (2) was refined as a two-component inversion twin.

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27

Huang, Zheng, Ziqing Zuo, Huanan Wen e Guixia Liu. "Cobalt-Catalyzed Hydroboration and Borylation of Alkenes and Alkynes". Synlett 29, n.º 11 (23 de abril de 2018): 1421–29. http://dx.doi.org/10.1055/s-0037-1609682.

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Incorporation of the boryl moiety across a carbon–carbon multiple bond is a powerful method for the synthesis of organoboron compounds. This kind of transformation could be realized with high chemo-, regio-, and stereoselectivity by using an appropriate transition-metal catalyst. This account summarizes the latest advances from our group in the area of cobalt-catalyzed hydroboration and borylation of alkenes and alkynes, which lead to the formation of a variety of organoboron compounds, including alkylboronates, 1,1,1-tris(boronates), 1,1-diborylalkenes, and 1,1-diboronates.1 Introduction2 Cobalt-Catalyzed Hydroboration of Alkenes3 Cobalt-Catalyzed Dehydrogenative Borylations-Hydroboration4 Cobalt-Catalyzed Double Dehydrogenative Borylations of 1-Alkenes5 Cobalt-Catalyzed Hydroboration of Terminal Alkynes6 Summary and Outlook

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28

Dumonteil, Geoffrey, e Sabine Berteina-Raboin. "Synthesis of Conjugated Dienes in Natural Compounds". Catalysts 12, n.º 1 (13 de janeiro de 2022): 86. http://dx.doi.org/10.3390/catal12010086.

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This review describes the various synthetic methods commonly used to obtain molecules possessing conjugated dienes. We focus on methods involving cross-coupling reactions using various metals such as nickel, palladium, ruthenium, cobalt, cobalt/zinc, manganese, zirconium, or iron, mainly through examples that aimed to access natural molecules or their analogues. Among the natural molecules covered in this review, we discuss the total synthesis of a phytohormone, Acid Abscisic (ABA), carried out by our team involving the development of a conjugated diene chain.

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29

Hadouchi, Mohammed, Abderrazzak Assani, Mohamed Saadi e Lahcen El Ammari. "The alluaudite-type crystal structures of Na2(Fe/Co)2Co(VO4)3and Ag2(Fe/Co)2Co(VO4)3". Acta Crystallographica Section E Crystallographic Communications 72, n.º 7 (24 de junho de 2016): 1017–20. http://dx.doi.org/10.1107/s2056989016009981.

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Single crystals of the title compounds, disodium di(cobalt/iron) cobalt tris(orthovanadate), Na2(Fe/Co)2Co(VO4)3, and disilver di(cobalt/iron) cobalt tris(orthovanadate), Ag2(Fe/Co)2Co(VO4)3, were grown from a melt consisting of stoichiometric mixtures of three metallic cation precursors and vanadium pentoxide. The difficulty to distinguish between cobalt and iron by using X-ray diffraction alone forced us to explore several models, assuming an oxidation state of +II for Co and +III for Fe and a partial cationic disorder in the Wyckoff site 8fcontaining a mixture of Co and Fe with a statistical distribution for the Na compound and an occupancy ratio of 0.4875:0.5125 (Co:Fe) for the Ag compound. The alluaudite-type structure is made up from [10-1] chains of [(Co,Fe)2O10] double octahedra linked by highly distorted [CoO6] octahedraviaa common edge. The chains are linked through VO4tetrahedra, forming polyhedral sheets perpendicular to [010]. The stacking of the sheets defines two types of channels parallel to [001] where the Na+cations (both with full occupancy) or Ag+cations (one with occupancy 0.97) are located.

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30

Vogel, Sabine, Gottfried Huttner e Laszlo Zsolnai. "Fünffach koordinierte Co(III)-Komplexe [Tripod-Cobalt-(ortho(X)(Y)C6H4)]+ mit ortho-phenylenverbrückten Chelatliganden [(XH)(YH)C6H4] (XH, YH = NH2, OH, SH) / Five-Coordinate Co(III) Complexes [Tripod-Cobalt-(ortho-(X)(Y)C6H4)]+ Containing ortho-Phenylene-Bridged Chelate Ligands [(XH)(YH)C6H4] (XH, YH = NH2, OH, SH)". Zeitschrift für Naturforschung B 48, n.º 5 (1 de maio de 1993): 641–52. http://dx.doi.org/10.1515/znb-1993-0514.

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The ortho-phenylene compounds ortho-[(XH)(YH)C6H4] (XH, YH = NH2, SH, OH) react with Co(BF4)2•6H2O and Tripod (CH3C(CH2PPh2)3) to give the five-coordinate Co(III) complexes [Tripod-Cobalt-(ortho-(X)(Y)C6H4)]+ (X, Y = NH, O, S), 1-6.The structures of 1—6 have been characterized by X-ray analyses of appropriate salts. The compounds have further been characterized by IR, NMR, UV-VIS and cyclovoltammetric measurements.As a compound analogous to 1—6, but containing the saturated chelate ligand [(S)C2H4(S)]2- instead of the conjugated ortho-phenylene type ligands of 1-6, [Tripod-Cobalt-((S)C2H4(S))]+, 7, has been prepared and fully characterized. It is inferred that the coordination geometries of 1-7 do not strongly depend on conjugative interaction within the chelating ligands.

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31

Hayami, Shinya, Manabu Nakaya, Hitomi Ohmagari, Amolegbe Saliu Alao, Masaaki Nakamura, Ryo Ohtani, Ryotaro Yamaguchi, Takayoshi Kuroda-Sowa e Jack K. Clegg. "Spin-crossover behaviors in solvated cobalt(ii) compounds". Dalton Transactions 44, n.º 20 (2015): 9345–48. http://dx.doi.org/10.1039/c4dt03743j.

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32

Andreiev, V. "Solidago canadensis L. — potential bioremeditor of contaminated soil". Karantin i zahist roslin, n.º 2-3 (19 de março de 2020): 24–28. http://dx.doi.org/10.36495/2312-0614.2020.2-3.24-28.

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Goal. To determine the patterns of contamination adjacent to the motor road Kyiv — Odesa territories of the soil and the specificity of uptake by wild plants (zolotarnica canadian Solidagoсanadensis L.) pollutants. Methods. Field and laboratory studies. Results. The products of combustion of car engines moving along the freeway, there are a variety of chemical compounds, including metals — lead (Pb), chromium (Cr), cobalt (Co), and others. In soil samples taken at a distance of 5 m from the motorway, the presence of lead compounds was 11.401 mg/ kg, chromium — 19.361 mg/kg. At a distance of 1280 m from the roadway of the motorway in the soil was lead compounds 6,845 mg/kg, chromium — 5.376, cobalt — 0.271 mg/kg In the aboveground parts of plants of the canadian goldenrod (leaves, stems) high concentrations of the compounds were recorded in the samples that were selected at a distance of 5 m from the road: lead — 5.136 mg/kg, chromium — 6.366, cobalt — 3.158 mg/kg. At a distance of 5 m from the motorway in the underground parts of plants that are perennial organs, the concentration of lead compounds reached 2.763 mg/kg, chromium — 3.642, cobalt — 2.034 mg/kg. the distance from the motorway 1280 m recorded in the leaves of Canada goldenrod concentration of lead compounds in an average of 2.675 mg/kg, compared with the figures from the motorway (distance 5 m) 1.92 times, chromium — 1.614 (3.94 times less compared to the maximum accumulation in the experiments), compounds of cobalt — 0.165 mg/kg (in 19.1 times less). Conclusions. Accumulation of heavy metals in aerial parts of plants (leaves and stems) Canada goldenrod that grows near the road above (lead 1.86 times, 1.75 chromium, cobalt 1.55 times) compared with perennial underground parts of plants. The research results prove the feasibility of practical use of the canadian goldenrod as bioremediator contaminated soils of areas adjacent to roads with heavy traffic, and its sound practical economic use.

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33

Bedi, S. C., e M. Forker. "Hyperfine interactions at Ta impurities in cobalt and cobalt-hafnium intermetallic compounds". Physical Review B 47, n.º 22 (1 de junho de 1993): 14948–60. http://dx.doi.org/10.1103/physrevb.47.14948.

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34

Balasubramanian, Balamurugan, Xin Zhao, Shah R. Valloppilly, Sumit Beniwal, Ralph Skomski, Anandakumar Sarella, Yunlong Jin et al. "Magnetism of new metastable cobalt-nitride compounds". Nanoscale 10, n.º 27 (2018): 13011–21. http://dx.doi.org/10.1039/c8nr02105h.

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35

Umehara, I., T. Kuwai, J. Sakurai, K. Maezawa, Q. F. Lu e K. Sato. "Thermopower of rare earth-cobalt compounds R3Co". Physica B: Condensed Matter 206-207 (fevereiro de 1995): 405–7. http://dx.doi.org/10.1016/0921-4526(94)00473-9.

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36

Burzo, E. "Spin fluctuations in cobalt rare-earth compounds". Journal of Magnetism and Magnetic Materials 140-144 (fevereiro de 1995): 2013–14. http://dx.doi.org/10.1016/0304-8853(94)01448-5.

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37

Burkin, A. R. "Nickel and cobalt extraction using organic compounds". Endeavour 10, n.º 4 (janeiro de 1986): 215–16. http://dx.doi.org/10.1016/0160-9327(86)90111-0.

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38

Li, Qin, Qingdong Ke e Max Costa. "Alterations of histone modifications by cobalt compounds". Carcinogenesis 30, n.º 7 (17 de abril de 2009): 1243–51. http://dx.doi.org/10.1093/carcin/bgp088.

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39

Varbanets, L. D. "THE COORDINATION COMPOUNDS OF COBALT (II, III)". Biotechnologia Acta 6, n.º 1 (2013): 73–80. http://dx.doi.org/10.15407/biotech6.01.073.

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40

Hughes, M. A. "Nickel and cobalt extraction using organic compounds". Hydrometallurgy 16, n.º 1 (abril de 1986): 120. http://dx.doi.org/10.1016/0304-386x(86)90059-9.

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41

Miura, Masahiro, Masato Shinohara e Masakatsu Nomura. "Cobalt-catalyzed reduction of aromatic nitro compounds". Journal of Molecular Catalysis 45, n.º 2 (maio de 1988): 151–53. http://dx.doi.org/10.1016/0304-5102(88)80002-6.

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42

Coles, B. R., e A. K. Chhabra. "Conditions for ferromagnetism in cobalt intermetallic compounds". Journal of Magnetism and Magnetic Materials 54-57 (fevereiro de 1986): 1039–40. http://dx.doi.org/10.1016/0304-8853(86)90371-9.

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43

Brescia, Tyler K., Kaltrina Mulosmani, Shivani Gulati, Demosthenes Athanasopoulos e Rita K. Upmacis. "Crystal structure of hexakis(dimethyl sulfoxide-κO)cobalt(II) bis[trichlorido(quinoline-κN)cobaltate(II)]". Acta Crystallographica Section E Crystallographic Communications 74, n.º 3 (7 de fevereiro de 2018): 309–12. http://dx.doi.org/10.1107/s2056989018001652.

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There are few reports that describe crystal structures of compounds containing cobalt complexed to either dimethyl sulfoxide (Me2SO) or quinoline (C9H7N). The title compound, [Co(C2H6OS)6][CoCl3(C9H7N)]2, is a cobalt salt in which the metal ion is complexed to both Me2SO and quinoline. In particular, we observed that anhydrous cobalt(II) chloride reacts with quinoline in Me2SO to form a salt that is to be formulated as [CoII(Me2SO)6]2+{[CoIICl3quinoline]2−}. The CoIIatom in the cation portion of this molecule lies on a inversion center and is bound to the O atoms of six Me2SO moieties in an octahedral configuration, while the CoIIatom in the anion is attached to three chloride ligands and one quinoline moiety in a tetrahedral arrangement.

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44

Reinig, Regina R., Ellie L. Fought, Arkady Ellern, Theresa L. Windus e Aaron D. Sadow. "Cobalt(ii) acyl intermediates in carbon–carbon bond formation and oxygenation". Dalton Transactions 47, n.º 35 (2018): 12147–61. http://dx.doi.org/10.1039/c8dt02661k.

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45

Munteanu, Catherine R., e Kogularamanan Suntharalingam. "Advances in cobalt complexes as anticancer agents". Dalton Transactions 44, n.º 31 (2015): 13796–808. http://dx.doi.org/10.1039/c5dt02101d.

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This perspective describes the advances in cobalt-containing compounds as anticancer agents. Cobalt, being an essential trace element, offers a less toxic alternative to traditional platinum-based anticancer drugs.

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46

Wu, Caizhi, e Shaozhong Ge. "Ligand-controlled cobalt-catalyzed regiodivergent hydroboration of aryl,alkyl-disubstituted internal allenes". Chemical Science 11, n.º 10 (2020): 2783–89. http://dx.doi.org/10.1039/c9sc06136c.

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The first cobalt-catalyzed stereoselective regiodivergent hydroboration of internal allenes to access synthetically versatile (Z)-alkenylboronate compounds was effectively achieved with two cobalt catalysts through ligand control.

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47

Curtis, NF, GJ Gainsford, P. Osvath e DC Weatherburn. "The Crystal and Molecular-Structure of Two Complexes of Cobalt(III) With Pentaaza Macrocyclic Ligands Chloro (1,4,7,10,14-pentaazacycloheptadecane)cobalt(III) Bromide Chloride Hydrate [Co(C12H29N5)Cl] (Br0.33Cl1.67)H2O and Bromo(1,4,7,11,15-pentaazacyclooctadecane)cobalt(III) Bromide [Co(C13H31N5)Br]Br2". Australian Journal of Chemistry 40, n.º 5 (1987): 829. http://dx.doi.org/10.1071/ch9870829.

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The structures of the compounds chloro (1,4,7,10,14-pentaazacycloheptadecane) cobalt(III) bromide chloride hydrate, [Co( chad )Cl] ( Br0.33Cl1.67)H2O(1) and bromo (1,4,7,11,15-pentaazacyclooctadecane) cobalt(III) bromide, [Co( coad )Br]Br2(2),have been determined by X-ray diffractometry. [Compound (1) orthorhombic, space group P bac, a 1208.5, b 2305.5, c 1318.9 pm, Z 8, R 0.056, Rw 0.071 for 1943 reflections. Compound (2), triclinic, space group P1, a 930.8, b 953.5, c 1120.3pm, α 84.60,β 398.82, γ 105.26�, Z 2, R 0.045, RW0.054 for 4821 reflections.] The compounds have structures with two ( chad ) or three ( coad ) six-membered chelate rings in the equatorial (N4) plane, but with different configurations of the chiral nitrogen centres ; chad : 1SR , 4SR, 7RS, 10RS, that is, with only the NH group at the junction of the two six-membered chelate rings on the same side of the N4 plane as the axial nitrogen; coad : 1 RS, 7SR, 11 SR, 15RS, that is, with NH groups of the central six-membered chelate ring on the same side of the N4 plane as the axial nitrogen, and the others on the opposite side. The chad compound has regular octahedral geometry, with one chair and one boat conformation six-membered chelate ring. The coad compound has distorted octahedral geometry, with long Co-N distances in the N4 plane, attributed to intra-ligand interactions.

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48

Geue, RJ, WR Petri, AM Sargeson e MR Snow. "Metal Ion Cages: Capping Reactions With Bifunctional Methylene Compounds and Formaldehyde". Australian Journal of Chemistry 45, n.º 10 (1992): 1681. http://dx.doi.org/10.1071/ch9921681.

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[(1,1,1-Tris(4-amino-2-azabutyl)ethane)cobalt(III)](3+) ([co(sen)]3+) and [(tris(4-amino-2- azabutyl)amine)cobalt(III)](3+) ([Co(azasen)]3+) react with formaldehyde and diethyl malonate or cyanoacetic acid ethyl ester in the presence of base to form macrobicyclic cages [ox- osarcophagine (oxosar) and oxoazasarcophagine (azaoxosar)] about the metal ion. The cage structure of the complexes has been established by an X-ray crystallographic analysis of [(1-carboxy-8-methyl-2-oxo-3,6,10,13, 16,19-hexaazabicyclo[6.6.6]icosanato)cobalt(III)] diperchlorate [Co(Me,CO2H-oxosar- H)]2+ which crystallizes in the orthorhombic space group Pbcn, with cell parameters a 33.61, b 10.42, c 13.743 � , and V 4813 � 3 , and Z 8. The chiral cobalt(III) complex is characteristically inert to substitution and racemization, but the cobalt(II) complex, obtained by reduction of the appropriate cobalt(III) compound, is surprisingly stable both to loss of Co2+ ion and to racemization at 25°C (pH 7.1, t½4.5 days). The syntheses, spectroscopic and chemical properties are reported. The kinetics of the electron self exchange for the cage system [Co(Me,CO2Et-oxosar-H)]+/2+, and of H2O2 formation from [coII(Me,co2Et-oxosar - H)]+ and O2 are reported. Similar syntheses have been carried out to half-cap the [co(en)3]3+ ion (en = ethane-1,2-diamine). These and related reactions have allowed substituents such as COOR, COOH, CN, COCl, CONR2, NH2 and NO2 to be placed on the bridgehead carbon atoms, and have altered the redox potentials of the systems by at least 0.3 V. The oxosar COII ions are useful as powerful reducing agents [from c. -0.3 to -0.6 V (v. n.h.e.)], and the cages are capable of further derivatization to build larger macromolecules.

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49

Golubev, D. V., E. V. Savinkina, A. Al-Khazraji e M. N. Davydova. "THERMAL DECOMPOSITION OF UROTROPINE COMPLEXES WITH NICKEL AND COBALT CHLORIDES". Fine Chemical Technologies 12, n.º 2 (28 de abril de 2017): 34–41. http://dx.doi.org/10.32362/2410-6593-2017-12-2-34-41.

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Complex compounds NiCl2·2HMTA·10H2O (1), CoCl2·2HMTA·10H2O (2), CoCl2·HMTA·4.5H2O (3) were prepared by the reaction of nickel(II) and cobalt(II) chlorides with urotropine (HMTA). Compounds 1 and 2 are isostructural, their structure corresponds to the earlier studied crystal structure [Ni(H2O)6]Cl2·4H2O·2HMTA. Thermal destruction of the complex compounds 1-3 was studied by TGA and high-temperature IR-spectroscopy. The TGA curve for compound 1 shows stepwise mass loss caused by two-stage loss of all water molecules (up to 170°C) and one urotropine molecule (up to 270°C) followed by decomposition of NiCl2·HMTA. The X-ray diffraction pattern of the resulting solid shows no reflections typical for the metal and its simplest nitrogen-, carbon- and chlorine-containing compounds. Thermal decomposition of сompounds 2 and 3 proceed similarly, but water is removed in one stage. IR spectra, which were recorded at high temperature (up to 220-230°C) show gradual decrease of intensity of the bands assigned to vibrations of water molecules. The bands of the methylene groups of urotropine do not change on heating. However, the bands of the C-N vibrations shift from ~1050 and ~1008 cm-1 in the spectra of urotropine and [M(H2O)6](HMTA)2Cl2·4H2O to 1015-1019 and 984-995 cm-1, respectively, indicating coordination of urotropine molecules instead of the removed water molecules. The long-wave IR spectra for NiCl2·6H2O and compound 1 at ambient temperature show bands of Ni-O stretching vibrations and O-Ni-O bending vibrations. After heating 1 at 115° C, bands of Ni-N and Ni-Cl appear, which indicates the coordination of urotropine molecules and chloride ions after the removal of outer-sphere and inner-sphere water molecules.

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MATHEW, TESSYMOL, e SUNNY KURIAKOSE. "Cobalt(II) Porphyrins Supported on Crosslinked Polymer Matrix as Model Compounds". Journal of Porphyrins and Phthalocyanines 03, n.º 04 (abril de 1999): 316–21. http://dx.doi.org/10.1002/(sici)1099-1409(199904)3:4<316::aid-jpp136>3.0.co;2-z.

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Polymer-bound cobalt(II) porphyrins were studied for their dioxygen—binding capacity. Tetra—aminoporphyrins were anchored on a divinylbenzene (DVB)-crosslinked chloromethyl polystyrene network. The crosslinked, solid polymers were swelled in chloroform and the swollen polymers were used for the entire studies. Ortho-, meta- and para-substituted porphyrin systems were developed by adjusting the bonding position with the help of suitably substituted aminoporphyrins. The products were characterized by chemical and spectroscopic methods. Cobalt(II) complexes of polymeric porphyrins were synthesized and characterized by electronic and ESR spectral methods. The spectra gave evidence for the systematic variation of electronic properties in ortho, meta and para compounds and for the dioxygen-binding capacity of cobalt complexes. These results are discussed.

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