Zehra Altuntaş Bayır

Electrochemical properties of octakis(hydroxyethylthio)-substituted phthalocyanines

Cyclic voltammetry of octakis(hydroxyethylthio)-substituted phthalocyanines with 2H (H2OHETPc), Zn(II) (ZnIIOHETPc(−2)) and Co(II) (CoII(OHETPc(−2)) in the phthalocyanine core has been investigated in dimethylsulfoxide (DMSO), and some of the results were evaluated together with their absorption spectra in the visible range. The redox processes due to both aggregated and non-aggregated species were observed on the voltammograms of phthalocyanines with Zn(II). The effect of chloride ion on the cyclic voltammetry of CoIIOHETPc(−2) has been investigated in the DMSO/ClO4− couple. The comparison of cyclic voltammetry for CoIIOHETPc in the absence and presence of chloride ion showed that chloride ion does not bind to either Co(II) or Co(I) but does bind very strongly to Co(III). The detailed electrochemistry of CoIIOHETPc(−2) was investigated in terms of the Co(I)/Co(II) and Co(II)/Co(III) redox couples, and various equilibria related to the species coordinated to Co(II) and Co(III) in the phthalocyanine core.

Synthesis of phthalocyanines with tridentate branched bulky and alkylthio groups

Abstract The synthesis and characterisation of 4,5-octasubstituted metal free and metallo (ZnII and CoII) phthalocyanines carrying four alkylthio groups and four tridentate NNS substituents on periferal positions are reported. The distinct differences encountered in the newly synthesized compounds with four alkyl chains are their high solubility in common organic solvents, e.g. chloroform, dichlorometane, THF, acetone, DMF and DMSO and bathochromic shifts in the UV-Vis spectra in comparison with 4,5-substituted analogues with four chloro groups in addition to four branched bulky groups. 1H NMR spectroscopy also shows a smaller up field shift in all protons for newly synthesised phthalocyanines with respect to the latter compounds.

Dioxadiaza macrocycle-substituted phthalocyanines

Abstract New metallophthalocyanines (M=Cu, Ni, Co) have been synthesized from a 16-membered dioxadiaza macrocycle using an anhydrous metal salt (CuCN, NiCl 2 or CoCl 2 ). The new compounds have been characterized by elemental analyses, IR, NMR and electronic spectroscopy.

Synthesis and Characterization of New Unsymmetrically Substituted Phthalocyanines

Summary. Unsymmetric metallophthalocyanines (M=Zn, Co, Ni) carrying alkylthio and acetyloxyethylthio groups on peripheral positions were prepared from 4,5-bis-alkylthio-phthalonitrile, 4,5-bis-(acetyloxyethylthio)-phthalonitrile, and the corresponding anhydrous metal salts Zn(CH3COO)2, NiCl2, and CoCl2. The extremely soluble compounds were characterized by their IR, 1H NMR, and UV/Vis spectra. Their long wavelength absorption band was found to be bathochromically shifted; their solubility is superior to that of symmetrical phthalocyanines.

DNA and BSA binding studies of novel tetracationic phthalocyanines

The novel tetracationic metallophthalocyanines having diethylmethyl aminoethylsulfanyl groups on the periphery have been synthesized and characterized. The compounds tend to form aggregates in aqueous solutions. The aggregation of ZnPc4+ or CoPc4+, but not that of CuPc4+, was hindered by the addition of surfactants (Triton X-100 and Tween 20). Using absorption and fluorescence spectroscopic techniques, DNA and BSA binding properties of tetracationic ZnPc in the presence of the surfactants were also investigated.

Synthesis and electronic absorption studies of novel (trifluoromethyl)phenoxy-substituted phthalocyanines

The reaction of 4-[4-(trifluoromethyl)phenoxy]phenol with 4-nitrophthalonitrile in the presence of K2CO3 leads to formation of 4-[4-[4-(trifluoromethyl)phenoxy]phenoxy]phthalonitrile. Tetrakis[4-[4-(trifluoromethyl)phenoxy]phenoxy]-substituted metal-free phthalocyanine was achieved by tetramerization of the phthalonitrile in 2-(dimethylamino)ethanol, whereas metallophthalocyanines were prepared in the presence of zinc, cobalt, or copper salts. These compounds show high solubility in weakly and medium polar solvents, in strongly polar solvents (dimethylformamide, dimethylsulfoxide), and in aromatic hydrocarbons (toluene, benzene). The new phthalocyanines were characterized by elemental analyses, 1H nuclear magnetic resonance (NMR), 13C NMR, 19F NMR, ultraviolet-visible (UV-Vis), Fourier-transform infrared (FT-IR), and mass spectroscopic methods.Graphical Abstract

Synthesis and Characterization of Phthalocyanines Containing Four 11-Membered Triaza Macrocycles

New metallophthalocyanines (M=Cu, Zn, Ni or Co) substituted in peripheral positions with four 11-membered triaza macrocycles are prepared from 1,4,7-tris(p-tolylsulfonyl)-1,4,7-triazaheptane and 1,2-dibromo-4,5-bis(bromomethyl)benzene or the corresponding anhydrous metal salt [CuCN, Zn(O2CMe)2, NiCl2 or CoCl2].

Corrosion Inhibition Effect of 4-(2-Diethylamino-Ethylsulfonyl)-Phthalonitrile and 4,5-Bis(Hexylsulfonyl)-Phthalonitrile

Inhibition of stainless steel corrosion in a 3.0 M NaCl solution by 4-(2-diethylamino-ethylsulfanyl)-phthalonitrile (DAESPN) and 4,5-bis(hexylsulfonyl)-phthalonitrile (Bis-HSPN) was investigated by polarization and electrochemical impedance spectroscopy (EIS) measurements. The values of cathodic (βc) and anodic (βa) Tafel slopes, 𝑖corr, 𝐸corr, corrosion rate (CR), and inhibition efficiences (IE%) obtained from polarization curves and polarization resistance (𝑅P), double-layer capacitance (𝐶dl), specific capacitance (𝐶sp) values were obtained from EIS. Double-layer capacitance differences in the presence and absence of inhibitors were also obtained from EIS measurements as suggested in the literature in order to investigate the interaction of them with metal surface. Results show that both DAESPN and Bis-HSPN are effective in cathodic reaction. Impedance measurements suggest higher surface coverage for DAESPN. The interaction between the inhibitor and the stainless steel was investigated by the adsorption isotherm. Langmuir adsorption isotherm 𝐾ads was applied and Δ𝐺 values were obtained and found as 4.32×10−4, 1.17×10−4 and 9.2 kJ, 12.5 kJ for DAESPN and Bis-HSPN, respectively, which suggests the electrostatic interaction between charged metal surface and charged organic molecules.

Substituted 2,2′-azoquinoxaline palladium(II) complexes

Abstract2,2′-Azobis(5,6-dimethylquinoxaline) was prepared by reacting 5,6-dimethylquinoxalinone-2(1 H)-one oxime with CoCl2. Binuclear cyclopalladated azoquinoxaline complexes were prepared from the corresponding quinoxalin-2(1 H)-one oxime and Pd(OAc)2.

A Convenient New Route to Perimidine-2-formaldoxime, 2,2′-Biperimidine and Its Metal Complexes

Abstract 2,2′-Biperimidine and perimidine-2-formaldoxime have been prepared by an one-pot reaction of E,E-dichloroglyoxime or anti-monochloroglyoxime with 1,8-diaminonaphthalene. Metal complexes of 2,2′-biperimidine are also described. Referee I: M. M. Jones Referee II: R. F. Johnson