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A. Yu. Tsivadze - One of the best experts on this subject based on the ideXlab platform.

  • Octa- and tetra-(Benzo-15-Crown-5)phthalocyanines in surfactant-containing solutions
    Protection of Metals and Physical Chemistry of Surfaces, 2011
    Co-Authors: N. F. Gol’dshleger, V. E. Baulin, I. P. Kalashnikova, A. Yu. Tsivadze
    Abstract:

    The behavior of octa-(Benzo-15-Crown-5)phthalocyanine (H2cr8Pc), as well as cobalt octa- and tetra-(Benzo-15-Crown-5)phthalocyaninates (Cocr8Pc and Cocr4Pc), in aqueous solutions containing cationic or anionic surfactants, such as cetyl trimethylammonium bromide (CTAB), sodium carboxymethyl cellulose (Na-CMC), and sodium dodecyl sulfate (SDS), is studied using electronic spectroscopy. The presence of eight Benzo-15-Crown-5 ether fragments on the periphery of the phthalocyanine ring is shown to facilitate the dissolution of Pc in an aqueous environment. The interactions between CTAB and crown-containing Pc promotes the dissolution of H2cr8Pc; Cocr8Pc; and, to a lesser degree, Cocr4Pc, which is accompanied by the appearance of molecular aggregates, including heteronuclear cofacial dimers. The presence of a metal in the ring is not the necessary condition of the process. In microscopically heterogeneous medium, such as an aqueous SDS-containing solution, H2cr8Pc is present in monomeric form at SDS concentrations close to Ccr and in dimeric form at SDS content below Ccr. Under similar conditions (environment, surfactant), Cocr4Pc can exist in monomeric form at SDS concentrations much high than Ccr. The effect of the size of cation on the form of the crown-containing Pc in an aqueous solution is illustrated by an example of H2cr8Pc. Na-CMC promotes the dissolution of Pc and enables one to produce K+/Mcr8Pc-modified films from aqueous solutions.

  • Coordination compounds of sodium, potassium, and calcium with Benzo-15-Crown-5-substituted terpyridines
    Russian Journal of Coordination Chemistry, 2010
    Co-Authors: N. M. Kurochkina, V. E. Baulin, E. N. Pyatova, I. S. Ivanova, A. Yu. Tsivadze
    Abstract:

    Sodium and potassium complexes with 4′-(4‴-Benzo-15-Crown-5)methyloxy-2,2′:6′,2″-terpyridine (L^1) and 4′-(4′-Benzo-15-Crown-5)oxy-2,2′:6′,2″-terpyridine (L^2) and heteronuclear Na, K, Ca, and transition metal complexes with L^1 were synthesized. The structure of the complexes was proposed on the basis of elemental analysis data, IR spectra, and the results of earlier X-ray diffraction studies of L^2, [NaL^1NCS], and [Na_2{Cu(L^1)_2}(NCS)_3]NCS · CH_3CN.

  • Synthesis, vibrational spectra, and structure of 4′-(4″-Benzo-15-Crown-5)oxy-2,2′:6′,2″-terpyridine (L) and its transition metal complexes. Extraction and ion-selective properties of L
    Russian Journal of Coordination Chemistry, 2009
    Co-Authors: N. M. Logacheva, E. N. Pyatova, V. E. Baulin, I. S. Ivanova, A. Yu. Tsivadze
    Abstract:

    Complexes of Co(II), Ni(II), Zn(II), and Cu(II) perchlorates and hexafluorophosphates with 4′-(4″-Benzo-15-Crown-5)oxy-2,2′:6′,2″-terpyridine (L) [M(L)_2](ClO_4)_2 · 3H_2O and [M(L)_2](PF_6)_2 · 2H_2O were synthesized. The spectral criteria of ligand coordination through the terpyridine nitrogen atoms were established. An assumption concerning the Benzo-15-Crown-5 conformation in the ligand molecule in the synthesized complexes was made. The extraction and ion-selective properties of L were studied.

  • Syntheses and structures of Osmium(II) and Osmium(VI) meso-tetra(Benzo-15-Crown-5)porphyrinates according to the spectral data
    Russian Journal of Inorganic Chemistry, 2009
    Co-Authors: Yu. A. Plachev, A. Yu. Chernyadyev, A. Yu. Tsivadze
    Abstract:

    The reaction of meso-tetra(Benzo-15-Crown-5)porphyrin (H2TCP) with the osmium carbonyl complex Os3(CO)12 yieds the corresponding osmium(II) porphyrinate OsTCP(CO). The oxidation of OsTCP(CO) with air oxygen and hydrogen peroxide in neutral and acidic media was studied. A preparative method for the synthesis of osmium(VI) meso-tetra(Benzo-15-Crown-5)porphyrinate (OsO2) TCP by the oxidation of OsTCP(CO) with 50% hydrogen peroxide in acetic acid was developed. The structures of new osmium porphyrinates were determined by IR, 1H NMR, and UV/Vis spectroscopies.

  • Complexes of sodium and lithium borohydrides with macrocyclic polyethers
    Russian Journal of Coordination Chemistry, 2007
    Co-Authors: A. Yu. Tsivadze, A. V. Dorokhov, A. Yu. Masanov, E. V. Nikitin, N. A. Votinova
    Abstract:

    A method for the synthesis of complexes of sodium and lithium borohydrides with crown ethers is proposed. The complexes of sodium borohydride with Benzo-15-Crown-5, 4′-aminoBenzo-15-Crown-5, dibenzo-18-crown-6, and diaza-18-crown-6 and the complexes of lithium borohydride with Benzo-15-Crown-5 and dibenzo-18-crown-6 are synthesized. These complexes can be used for the preparation of hydrogen in their reactions with methanol. The complex formation does not affect the purity of hydrogen formed.

Kung-kai Cheung - One of the best experts on this subject based on the ideXlab platform.

Zeliha Hayvali - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis, characterization, and antimicrobial activities of novel double-armed Benzo-15-Crown-5 and their sodium and potassium complexes:
    Journal of Chemical Research, 2020
    Co-Authors: Öznur Şener Cemaloğlu, Hatice Öğütcü, Zeliha Hayvali
    Abstract:

    New aldehyde- and halogen- (Cl, Br, I) substituted double-armed Benzo-15-Crown-5 derivatives are synthesized by the reactions of 4′,5′-bis(bromomethyl)Benzo-15-Crown-5 with 5-chlorosalicylaldehyde,...

  • Investigation of photophysical behaviours and antimicrobial activity of novel Benzo-15-Crown-5 substituted coumarin and chromone derivatives
    Journal of Molecular Structure, 2020
    Co-Authors: Duygu Şahin Gül, Hatice Öğütcü, Zeliha Hayvali
    Abstract:

    Abstract Two different series of crown ether compounds (4-11) were synthesized by the reactions of 4′,5′-bis(bromomethyl)Benzo-15-Crown-5 (3) and 4′-amino-Benzo-15-Crown-5 with hydroxycoumarin and chromone derivatives. Coumarin-crown ether compounds (4 and 5) were synthesized by the reactions of 4′,5′-bis(bromomethyl)Benzo-15-Crown-5 (3) with 4-hydroxycoumarin and 7-hydroxycoumarin. Chromone-crown ether compounds (6-11), were synthesized by the condensation reactions of 4′-amino-Benzo-15-Crown-5 with 3-formylchromone and 6-methyl-3-formylchromone in different solvent media. Sodium and potassium complexes (4a-11a, 4b-11b) of new coumarin and chromone substituted Benzo-15-Crown-5 (B15C5) ligands (4-11) were prepared with NaSCN and KSCN, respectively. The syntheses of the novel crown ether compounds (4-11) and complexes (4a-11a, 4b-11b) were elucidated by the elemental analysis, FTIR, 1H NMR, 13C NMR and MS spectral data. The metal selectivities and effects of metal cations (Li+, Na+, K+, Mg2+, Ca2+, Ba2+, Ag+, Al3+, Cu2+, Zn2+, Ni2+, Pb2+, Fe3+, Cr3+) to the new crown ether compounds (4-11) were investigated by the absorption and fluorescence spectra. In addition, all of these substances were examined for antibacterial activity against pathogenic strains Listeria monocytogenes 4b, Staphylococcus aureus, Escherichia coli, Salmonella typhi H, Bacillus cereus, Micrococcus luteus, Shigella dysenteria type 2, Staphylococcus epidermidis, Proteus vulgaris, Klebsiella pneumonia sp., Serratia marcescens sp. and antifungal activity against Candida albicans.

  • Syntheses and spectroscopic characterization of double-armed Benzo-15-Crown-5 derivatives and their sodium and potassium complexes
    Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2012
    Co-Authors: Zeliha Hayvali, Pinar Köksal
    Abstract:

    A series of new Benzo-15-Crown-5 derivatives (1–6) containing formyl and imine groups were prepared. New formyl crown ethers (1 and 2) were prepared by reaction of 4′,5′-bis(bromomethyl)Benzo-15-Crown-5 with 2-hydroxy-3-methoxybenzaldehyde (o-vanillin) and 2-hydroxy-5-methoxybenzaldehyde in the presence of NaOH. New Schiff bases (3–6) were synthesized by the condensation of corresponding aldehydes with 1,3-diaminopropane and 1,4-diaminobutane. Sodium and potassium complexes (1a–6a and 1b–6b) of the crown compounds forming crystalline complexes of 1:1 (Na+:ligand) and 1:2 (K+:ligand) stoichiometries were also synthesized. The structures of the aldehydes 1 and 2, imines 3–6 and complexes (1a–3a and 1b–3b) were confirmed on the basis of elemental analyses, IR, 1H- and 13C-NMR, and mass spectroscopy.

  • Syntheses, spectroscopic characterization and metal ion binding properties of Benzo-15-Crown-5 derivatives and their sodium and nickel(II) complexes
    Journal of Inclusion Phenomena and Macrocyclic Chemistry, 2012
    Co-Authors: Duygu Sahin, Zeliha Hayvali
    Abstract:

    New Benzo-15-Crown-5 derivatives containing nitro, amine and imine groups were prepared. Nitro compound ( 1 ) was prepared after the reaction 4′,5′-bis(bromethyl)Benzo-15-Crown-5 and o -nitrophenol in the presence of NaOH. After reduction process by using hydrazine hydrate and Pd/C amine compound ( 2 ) was formed. New crown ether imine compounds ( 3 – 5 ) were synthesized by the condensation of corresponding crown ether diamine ( 2 ) with salicylaldehyde derivatives. Sodium complexes of the crown compounds ( 1a – 5a ) form crystalline 1:1 (Na^+: ligand) complexes with sodium perchlorate. Nickel(II) complexes ( 3b – 5b ) with 1:1 (Ni^2+:ligand) stoichiometries were also been synthesized from the Schiff bases ( 3 – 5 ). The results indicated that the Schiff base ligands coordinated through the azomethine nitrogen and phenolic oxygen. The extraction ability of compounds ( 1 , 3 , 4 and 5 ) were also evaluated in chloroform by using several alkali and transition metal picrates such as Li^+, Na^+, K^+, Cr^3+, Mn^2+, Ni^2+, Cu^2+, Zn^2+ and Pb^2+.

Malgorzata Joźwiak - One of the best experts on this subject based on the ideXlab platform.

  • the effect of properties of water organic solvent mixtures on the solvation enthalpy of 12 crown 4 15 crown 5 18 crown 6 and benzo 15 crown 5 ethers at 298 15 k
    Thermochimica Acta, 2004
    Co-Authors: Malgorzata Joźwiak
    Abstract:

    Abstract Crown ethers are preferential solvated by organic solvents in the mixtures of water with formamide, N -methylformamide, acetonitrile, acetone and propan-1-ol. In these mixed solvents the energetic effect of the preferential solvation depends quantitatively on the structural and energetic properties of mixtures. The energetic properties of the mixtures of water with hydrophobic solvents ( N , N -dimethylformamide, dimethylsulfoxide, N , N -dimethylacetamide, hexamethylphosphortriamide) counteract the preferential solvation of the crown ether molecules. The effect of the hydrophobic and acid–base properties of the mixture of water with organic solvent on the solvation of 12-crown-4, 15-crown-5, 18-crown-6 and Benzo-15-Crown-5 ethers was discussed. The solvation enthalpy of one –CH 2 CH 2 O– group in water, N,N -dimethylformamide and hexamethylphosphortriamide is equal to −24.21, −16.04 and −15.91 kJ/mol, respectively. The condensed benzene ring with 15-crown-5 ether molecule brings about an increase in the exothermic effect of solvation of the crown ether in the mixtures of water with organic solvent.

Vivian Wing-wah Yam - One of the best experts on this subject based on the ideXlab platform.