Synthesis, Conductivity, and Impedance Studies on Metallophthalocyanines Formed Across Adjacent Rings

WOS: 000458689800005The synthesis and characterization of Co-II, Zn-II, and Ni-II phthalocyanines (Pcs) 4, 5, and 6, respectively, containing two bis[2-(4-hydroxyphenyl)-2-propyl]benzene groups formed across adjacent rings at the peripheral positions are described. The Pcs were synthesized by cyclotetramerization of the previously prepared precursor 4,4 '-bis[1,3-propylbenzene-2-p-phenoxy]phthalonitrile (3) in the presence of metal salt in boiling dry DMF under a dry nitrogen atmosphere. Elemental analysis, UV-Vis, FT-IR, and H-1-NMR spectroscopy, as well as MALDI-TOF mass spectrometry techniques were used for the characterization of 4. Conductivity (dc and ac) and impedance spectroscopy (IS) measurements were performed on the films of 5 and 6 between the temperatures 293 and 523 K and frequencies 40 and100 kHz. The dc conductivity values were calculated as 2.11 x 10-(10), 3.48 x 10-(10), and 1.90 x 10-(10) S/cm for the films of 4, 5, and 6, respectively, at room temperature. Activation energy values of the films were also calculated. Conductivity (ac) results suggest that the dominant charge transport mechanisms can be explained by the hopping model depending on temperature and frequency range. From impedance spectra and Cole-Cole plots, the relaxation time in the Debye dispersion relation is considered as a distribution of relaxation time values rather than as a single relaxation time. To elucidate the structural, spectroscopic, and bonding properties of the obtained compounds, DFT/TD-DFT calculations were performed.Scientific Research Commission of Marmara University (BAPKO)Marmara University [FEN-BGS-290506-0114]; Turkish Academy of Sciences (TUBA)Turkish Academy of SciencesThe authors gratefully acknowledge financial support by the Scientific Research Commission of Marmara University (BAPKO Project No: FEN-BGS-290506-0114), the Turkish Academy of Sciences (TUBA), and computer time on the FenCluster provided by the Ege University Faculty of Science and TUBITAK-ULAKBIM Truba Resources

Novel alpha-7-oxy-4-(4-methoxyphenyl)-8-methylcoumarin substituted metal-free, Co(II) and Zn(II) phthalocyanines: Photochemistry, photophysics, conductance and electrochemistry

Novel alpha-substituted metal-free. Co(II) and Zn(II) phthalocyanines, bearing four 7-oxy-4-(4-methoxyphenyl)-8-methylcoumarin moieties were synthesized. The compounds were characterized by elemental analysis, IR, UV vis, H-1 NMR, C-13 NMR and MALDI-TOF mass spectroscopies. The Zn(II) phthalocyanine compound showed J-type aggregation in non-coordinating solvents. The photophysical and photochemical properties of these compounds were described in different solvents. Direct current conductivity measurements of the films of Co(II) and Zn(II) phthalocyanines as a function of temperature showed that these compounds are semiconductors with the activation energies within the range of 0.40-0.84 eV. The variation of alternating current conductivity of the films with frequency was found to be represented by the function sigma(AC) = A omega(s). The results indicated that charge transport mechanism of the films can be explained by hopping. The redox properties of the compounds were also examined in dimethylsulfoxide and dichloromethane by voltammetry and in situ spectroelectrochemistry. The compounds displayed metal and/or phthalocyanine ring-based reduction and oxidation processes. The electrochemistry of a phthalocyanine compound forming a J-aggregated species has been investigated. It was found that some redox couples of the Zn(II) compound in dichloromethane is split due to the equilibrium between its aggregated and non-aggregated species. (C) 2012 Elsevier Ltd. All rights reserved

Synthesis, characterization, DFT study, conductivity and effects of humidity on CO2 sensing properties of the novel tetrakis- [2-(dibenzylamino)ethoxyl] substituted metallophthalocyanines

Acar-Selcuki, Nursel/0000-0001-9292-0637; senoglu, sema/0000-0002-1618-6570; Ozer, Metin/0000-0002-1173-2405WOS: 000519306300053Novel tetrakis[2-(dibenzylamino)ethoxyll substituted nickel (II), cobalt (II) and manganese (II) phthalocyanines were synthesized by using 4-(2-(dibenzylamino)ethoxy)phthalonitrile with corresponding metal salts in 2-N, N-dimethylaminoethanol. New phthalonitrile ligand was prepared from 2-(dibenzylamino)ethan-l-ol and 4-nitrophthalonitrile in acetonitrile at reflux temperature using potassium carbonate as catalyst. the compounds was characterized by elemental analysis, infrared, ultraviolet-visible and matrix-assisted laser desorption/ionization time-of-flight mass spectroscopic methods. Density functional theory calculations were performed for structural and electronic properties. Direct current and alternating current conductivity properties of the metallophthalocyanine films were investigated between 293 - 523 K and frequencies 40 -100 kHz. the direct current conductivity values were calculated as 5.29 x 10(-10 )S/cm, 2.39 x 10(-9)S/cm, and 3.04 x 10(-10) S/cm, for nickel, cobalt and manganese complexes (293 K) films, respectively. Activation energies of the films were 0.50-0.70 eV for T < 478 K. Alternating current conductivity results suggest that hopping model explains dominant charge transport mechanisms. Carbon dioxide sensing properties (1000-8000 ppm) of the metallophthalocyanine films were investigated at room temperature (293 K) in air as background. Additionally, effects of the relative humidity on carbon dioxide sensing properties were also investigated for relative humidity between 0-80 % RH in air. Response and response time values of the films were reported. Newly synthesized phthalocyanine complexes in this study were found to be reversible and sensitive to the carbon dioxide gas in humid air. Carbon dioxide sensing measurements revealed that sensitivity of the sensors increased with increasing carbon dioxide concentration and relative humidity. It is found that manganese phthalocyanine showed greater sensitivity than nickel- and cobalt phthalocyanine complexes.Ministry of Development-Republic of TurkeyTurkiye Cumhuriyeti Kalkinma Bakanligi [2016 K121230]; Turkish Academy of Science (TUBA)Turkish Academy of Sciences; Marmara University Scientific Research CommitteeMarmara University [FEN-CYLP-120917-0552, FEN-D-120418-0176, FEN-BGS-290506-0114]This work was supported by Ministry of Development-Republic of Turkey with the project Number: 2016 K121230. Ozer Bekaroglu and Bekir Salih gratefully acknowledge the Turkish Academy of Science (TUBA) for the partial financial support. Authors also thank to Marmara University Scientific Research Committee (Project Numbers: FEN-CYLP-120917-0552, FEN-D-120418-0176 and FEN-BGS-290506-0114) for their support. the authors are grateful to the TUBITAK-ULAKBIM Truba Resources for computer time