Ayşe Aktaş

Fluoro functional groups substituted cobalt(II), iron(II) phthalocyanines and their catalytic properties on benzyl alcohol oxidation

In this study, phthalocyanine complexes (Co and Fe) bearing (2-{2-[3-(trifluoromethyl)phenoxy]ethoxy}ethoxy) groups at peripheral position were synthesized using the phthalonitrile derivative and characterized by IR, 1H-NMR, UV–Vis and mass spectrometry. Catalytic activity of Co(II) and Fe(II) phthalocyanines were investigated in the oxidation of benzyl alcohol with different oxygen sources. Determination of the optimal conditions for oxidation of benzyl alcohol, the catalytic reactions were carried out change the reaction temperature, oxidant/cat ratio, types of oxidants and subst./catalyst ratio.

1,2,4-triazole-5(4H)-one based novel peripherally tetrasubstituted metal-free and metallophthalocyanines: Synthesis, characterization, and electrochemical and spectroelectrochemical properties

ABSTRACT In this study, the synthesis of metal-free and metallophthalocyanines containing four 4-[2-(4-methoxyphenyl)ethyl]-5-methyl-2,4-dihydro-3H-1,2,4-triazol-3-one substituents at the peripheral positions were reported. The structures of compounds were characterized using IR, 1H NMR, 13C NMR, mass spectroscopies, and UV-Vis. Electrochemistry of the complexes were studied with voltammetric and in situ spectroelectrochemical measurements in different electrolytic systems. MPcs having redox inactive metal centers (H+, Zn+2, Cu+2, and Ni+2) just illustrated similar Pc-based electron transfer reactions. Due to the different effective nuclear charge of the ions in the core of Pc ring, small potential shifts and reversibility differences were observed between the redox processes of these complexes. MPcs having redox-active metal centers (Co+2 and TiO+2) gave metal-based electron transfers in addition to Pc-based processes. Electrolyte type of the measurement system significantly influenced oxidation behaviors of CoPc due to the coordination of polar coordinating solvent molecules to the oxidized CoIII center of CoPc. Spectra and color of the electrogenerated MPc species were determined with in situ spectroelectrochemical measurements.

Synthesis and electrochemistry of new octa-substituted metal-free and metallophthalocyanines

The synthesis and characterization of metal-free (H2-Pc) and metal-containing (Zn, Co, and Cu) derivatives of a symmetrically octa-substituted phthalocyanine derived from 4,5-bis[2-(phenylthio)ethoxy]phthalonitrile were carried out by microwave irradiation. The electrochemical properties of the metal-free phthalocyanine 4 and metallophthalocyanine complexes 5 and 6 were investigated by cyclic voltammetry and differential pulse voltammetry. We have previously investigated the electrochemical properties of the tetra substituted 2-(phenylthio)ethoxy phthalocyanines. The reduction potential of the octa-substituted metal-free phthalocyanine shifted to more negative potential as a result of the electron donating of the 2-(phenylthio)ethoxy groups on the periphery compared to those of tetra substituted. The H2Pc and ZnPc demonstrated ligand-based electron transfer processes, while CoPc complex has a metal-based reduction process. Similar aggregation behavior was observed for octa-substituted phthalocyanines. The compounds were characterized using IR, 1H NMR, 13C NMR, elemental analysis, and MS spectral data. Graphical Abstract