Chemistry (Weinheim an der Bergstrasse, Germany), Jan 11, 2018
Bulk heterojunction (BHJ) solar cells might one day play a vital role in realizing low-cost and e... more Bulk heterojunction (BHJ) solar cells might one day play a vital role in realizing low-cost and environmentally benign photovoltaic devices. In this work, a BHJ solar cell was designed, based on a hexadeca-substituted phthalocyanine (FcPc) with ferrocenyl linked to the phthalocyanine ring. Next, we sought to obtain more quantitative information about the usability of this newly synthesized compound as a donor material in BHJ solar cells. Thus, BHJs with the structure of indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/FcPc:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend/LiF/Al were fabricated and characterized. The effect of blend ratio (0.5-2.0) on the BHJ solar cell parameters was also investigated. Interesting results were obtained in FcPc and the PCBM blend-based BHJ solar cell under optimized conditions. Our results presented here demonstrate that BHJ devices employing FcPc as a donor has great potential for the development of highly efficient no...
The recent advances in the synthesis of carborane and boronic ester-substituted tetrapyrroles (po... more The recent advances in the synthesis of carborane and boronic ester-substituted tetrapyrroles (porphyrins, porphyrazines, and phthalocyanines) are reviewed together with their possible utilization as agents for photodynamic therapy (PDT) and boron neutron capture therapy of cancer (BNCT) as well as dual PDT/BNCT sensitizers.
In this study, electrochemical behaviors of Co(II) and Pd(II) phthalocyanines carrying tetrakisdi... more In this study, electrochemical behaviors of Co(II) and Pd(II) phthalocyanines carrying tetrakisdiethoxymalonyl and Pd(II) phthalocyanine carrying tetrakiscarboxymethyl substituents at the peripheral positions are investigated by cyclic voltammetry and applied potential chronocoulometry techniques. Cyclic voltammetric studies show that, while Pd(II) phthalocyanines carrying diethoxymalonyl and carboxymethyl substituents give up to three common phthalocyanine ring reductions, Co(II) phthalocyanine carrying diethoxymalonyl substituents gives a
Magnesium porphyrazinate substituted with eight 4-tert-butylphenylthio-groups on the peripheral p... more Magnesium porphyrazinate substituted with eight 4-tert-butylphenylthio-groups on the peripheral positions has been synthesized by cyclotetramerization of 1,2-bis(4-tert-butylphenylthio)maleonitrile in the presence of magnesium butanolate. The metal-free derivative was obtained by its treatment with trifluoroacetic acid, and further reaction of this product with nickel(II) acetate led to the metal porphyrazinate (M = Ni). These new compounds have been characterized by elemental analysis, together with FT-IR, 1 H NMR and UV-Vis spectral data. The electronic properties of a spin coated film of NiPz have been studied by fabricating metal-insulator-semiconductor (MIS) capacitors. Current-voltage (I-V) and capacitancevoltage (C-V) measurements were carried out. It was observed that the Al/NiPz/p-Si structure exhibits rectifying behavior with a barrier height value of 0.89 eV and with an ideality factor value of 1.81. It was seen that this value of the obtained barrier height is remarkably higher than those given for metal/Si semiconductor contacts in the literature. The Lien, So and Nicolet method, combined with conventional forward I-V, was used to extract the series resistance value and it was found to be 26 kX. High frequency C-V measurements were used to determine the mobile oxide charge in the NiPz layer and this was found to be 1.6 Â 10 11 cm À2 .
Magnesium porphyrazinate substituted with eight (1-naphthylmethylthio) groups on the peripheral p... more Magnesium porphyrazinate substituted with eight (1-naphthylmethylthio) groups on the peripheral positions has been synthesized by cyclotetramerization of 1, 2-bis (1-naphthylmethylthio) maleonitrile in the presence of magnesium butanolate. The metal-free ...
Voltammetric and spectroelectrochemical characterization of the metallo-porphyrazines (M=2H+, Mg2... more Voltammetric and spectroelectrochemical characterization of the metallo-porphyrazines (M=2H+, Mg2+, Cu2+, Zn2+ and Co2+) substituted with eight (1-naphthylmethylthio) groups on the peripheral positions are described. Cyclic voltammetry and differential pulse voltammetry studies show that while metal-free, magnesium, zinc, and copper porphyrazine complexes give three ligand-based reductions and one ligand-based oxidation couple having diffusion controlled one-electron reversible character, cobalt porphyrazine gives both
Co(II) and Cu(II) complexes and metal-free t-butylphenyl peripherally substituted porphyrazine (P... more Co(II) and Cu(II) complexes and metal-free t-butylphenyl peripherally substituted porphyrazine (Pz) have been screened for in vitro antifungal (Aspergillus niger) and antioxidant (free radical scavenging, superoxide radical scavenging, and reducing power) activities. The results were compared with synthetic antioxidants, e.g., butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), trolox, or α-tocopherol. The free radical scavenging activity of H2Pz was higher than the CuPz
Novel, aryloxy-and arylalkyloxy-substituted pyrazine dicarbonitriles were synthesized from 5,6dic... more Novel, aryloxy-and arylalkyloxy-substituted pyrazine dicarbonitriles were synthesized from 5,6dichloropyrazine-2,3-dicarbonitrile and the corresponding phenol/alcohol derivatives. Cyclotetramerisation of these pyrazine derivatives to form metal pyrazinoporphyrazines in the presence of appropriate metal salts in different solvents such as DMF, quinoline, 2-dimethylaminoethanol and n-hexanol, resulted in decomposition products with the exception of teh latter solvent which lead to mainly octakis(alkyloxy) pyrazinoporphyrazines. Cyclic voltammetry and differential pulsed voltammetry of the complexes indicated that cobalt pyrazinoporphyrazine displayed both ligand and metal-based redox processes while zinc and copper derivatives exhibited only ligand-based redox processes. The redox processes of the pyrazinoporphyrazines shifted significantly towards positive potentials compared to those of the common phthalocyanines. The novel compounds were characterised using elemental analysis and spectral techniques.
A new phthalonitrile derivative bearing hexyloxy groups in the 3,6-positions and p-sulfonylphenox... more A new phthalonitrile derivative bearing hexyloxy groups in the 3,6-positions and p-sulfonylphenoxyand chloro groups in the 4 and 5-positions was synthesized. The new hexadeca-substituted zinc phthalocyanine was obtained by cyclotetramerisation of this phthalonitrile derivative in the presence of anhydrous zinc acetate under microwave heating. The aggregation behavior of the amphiphilic zinc phthalocyanine was studied in methanol and water. All novel compounds have been characterized by using elemental analysis, UVeVis, FT-IR, 1 H NMR and MS spectroscopic data. The photosensitizing activity of this phthalocyanine dye was evaluated by application of 1,3-diphenylisobenzofuran as a singlet oxygen chemical quencher. In cell culture media the phthalocyanine showed a cytotoxic effect on HepG2 cells; a feature which encourages future in vivo studies.
A pyrazinedinitrile derivative carrying dimethylaminoethylsulphanyl groups at positions 5 and 6 w... more A pyrazinedinitrile derivative carrying dimethylaminoethylsulphanyl groups at positions 5 and 6 was synthesised from 2-dimethylaminoethanethiol hydrochloride and 2,3-dicarbonitrile-5,6-dichloropyrazine. The dicarbonitrile gave magnesium azaphthalocyanine (MgAzaPc) when reacted with magnesium propoxide in propanol. The conversion of the MgAzaPc to a metal-free derivative was achieved by treatment with trifluoroacetic acid. Incorporation of transition metal ions into the inner core of azaphthalocyanine was accomplished by treatment of the metal-free derivative with metal acetates, i.e. Zn(OAc) 2 , Co(OAc) 2. These azaphthalocyanines were converted into water-soluble quaternised products by reaction with methyl iodide. Aggregation phenomena were followed for magnesium azaphthalocyanine with quaternisable dimethylamino substituents within a specific range of pH. The compounds were characterised by Fourier transform-infrared, proton nuclear magnetic resonance, mass and ultraviolet-visible spectral data.
Zeitschrift für anorganische und allgemeine Chemie, 2008
Porphyrazines, MPz (M = Mg, H, Ni, Zn and Co) with octakis 3‐methylbutylthio substituents have be... more Porphyrazines, MPz (M = Mg, H, Ni, Zn and Co) with octakis 3‐methylbutylthio substituents have been synthesized starting with the corresponding unsaturated dicarbonitrile derivative. These new compounds have been characterized by UV‐Vis, FT‐IR, 1H NMR, MS and elemental analysis methods. Voltammetric properties of the complexes were also investigated by CV, DPV and CPC techniques. Electrochemical studies show that three reversible one electron reductions and one reversible one electron oxidation processes (two for CoIIPz) are observed for all of the complexes. The E1/2 values are similar for the H2Pz, NiIIPz and ZnIIPz derivatives with negative shift due to the different effective nuclear charges of the central metal ion. Peak to peak separations and separation between the first reduction and first oxidation couples related with the HOMO‐LUMO gap of the complexes are in harmony with the common porphyrazine complexes.
ABSTRACT In this work, a new hexadeca substituted zinc phthalocyanine 4 bearing hexyloxy groups i... more ABSTRACT In this work, a new hexadeca substituted zinc phthalocyanine 4 bearing hexyloxy groups in non-peripheral positions and 3-(diethylamino)phenoxy groups in peripheral positions and its corresponding water-soluble octacationic derivative 5 have been reported. The new compounds have been characterized by elemental analysis, IR, UV, NMR and mass spectra. Zinc phthalocyanine showed excellent solubility in organic solvents of wide polarity range due to its amphiphilic nature and it enabled us to carry out detailed UV-Vis studies in different solvents. Octacationic zinc phthalocyanine 5 was soluble in DMF, DMSO and water. UV-Vis spectra of 5 in DMSO, DMF and water showed sharp Q band absorption as an indication of monomeric form even in aqueous media. This property of water-soluble non-aggregating zinc phthalocyanine is promising as a photosensitizer in Photodynamic Therapy of Cancer.
The focus of the present work is to gain more insight into the electrochemical behavior of newly ... more The focus of the present work is to gain more insight into the electrochemical behavior of newly synthesized Co II , Zn II , Cu II , and Pd II phthalocyanines with tetra-tricarbethoxyethyl substituents at the peripheral position. A more exhaustive electrochemical study of the complexes was done to determine the desired wisdom for the usage of the complexes as a functional material. A comparative study of the voltammetric measurements of these complexes showed that while Zn II , Cu II , and Pd II phthalocyanines exhibited up to four common phthalocyanine ring reductions, Co II phthalocyanine gave a metal-centered oxidation, a reduction and a ligand-centered reduction process. By contrast observation of the splitting of the second reduction process of Pd II phthalocyanine suggests aggregation of the complex. Diffusion coefficients of all complexes were determined by both the cyclic voltammetry and the potential step chronocoulometry techniques. Diffusion coefficients of the reduced and oxidized forms of the redox couples of the complexes were also calculated by the potential step chronocoulometry technique. Diffusion coefficients of the reduced forms of the electrode products of the complexes were found to be slightly higher than that of the oxidized forms.
ABSTRACT In this study, the syntheses and characterization of [2,3,7,8,12,13,17,18-octakis [2-(3-... more ABSTRACT In this study, the syntheses and characterization of [2,3,7,8,12,13,17,18-octakis [2-(3-quinolincarboxy)ethylhio] porphyrazinato (NNNN24)-N-21-N-22-N-23] magnesium(II), quaternized [2,3,7,8,12,13,17,18-octakis [2-(3-quinolincarboxy)ethylhio] porpyrazinato (NNNN24)-N-21-N-22-N-23] magnesium(II), [2,3,7,8,12,13,17,18-octakis[2-(3-quinolinecarboxy)-ethylthio]21H23H (NNNN24)-N-21-N-22-N-23 porphyrazine and [2,3,7,8,12,13,17,18-octakis[2-(3-quinolinecarboxy)-ethylthio]porphyrazinato (NNNN24)-N-21-N-22-N-23} zinc are described. The new compounds have been characterized by elemental analysis, FT-IR, H-1-NMR, and mass spectra. General trends are described for fluorescence quantum yields of these compounds in dimethylsulfoxide (DMSO). In this study, the effects quaternization of the substituents on the photophysical and spectroscopic properties are also reported.
Bis(3-methylbutantio) maleonitril has been obtained from the reaction of disodium salt, 1-bromo-3... more Bis(3-methylbutantio) maleonitril has been obtained from the reaction of disodium salt, 1-bromo-3 methylb ü tan in acetone under nitrogen for 11 hours. MgPz has been synthesized through the cyclotetramerization reaction of magnesium and n-butanol with bis(3-methylbutantio) maleonitril. The metal free pophyrazine derivative was obtained by its treatment with trifluroacetic acid and further reaction of this product with cobalt(II) acetate, nickel(II) acetate and zinc(II) acetate led to the metal porphyrazine (MPz, M = Co, Ni ve Zn). These new compounds have been investigated and characterized by UV, FT-IR, 1 H NMR, GC-MS and elemental analysis methods.
Thin films of tetra (tricarbethoxy)-substituted metallophthalocyanines [where the metal was Cobal... more Thin films of tetra (tricarbethoxy)-substituted metallophthalocyanines [where the metal was Cobalt(II), Copper(II) or Palladium(II)] were prepared by spin coating technique. Optical properties of thin films were investigated by measuring the transmittance and reflectance using a spectrophotometer in the wavelength range of 350-1000 nm. The refraction index and extinction coefficient were determined. Surface microstructure of the films was observed by Atomic force microscopy. Also, the optical band gap and dielectric constant values were calculated.
The adsorption of [octakis(2-trimethylammoniumethylsulfanyl)-porphyrazinatocobalt]octaiodide from... more The adsorption of [octakis(2-trimethylammoniumethylsulfanyl)-porphyrazinatocobalt]octaiodide from aqueous solution onto negatively charged sepiolite is investigated. The effects of temperature, dye and solid concentration and contact time on adsorption were evaluated. Adsorption experiments were analyzed in the light of zeta potential measurements and desorption behavior of the dyeesepiolite composite. Experimental data were analyzed using four adsorption kinetic models, of which a pseudosecond-order kinetic model was found to be superior. Experimental equilibrium data were fitted to five adsorption isotherm models, from which the free energy, enthalpy and entropy of the adsorption processes were determined. Adsorption onto sepiolite was exothermic and spontaneous. AAS and FTIR were used to elucidate the adsorption mechanism. The novel composite is considered to be useful in optical and catalytic applications.
Chemistry (Weinheim an der Bergstrasse, Germany), Jan 11, 2018
Bulk heterojunction (BHJ) solar cells might one day play a vital role in realizing low-cost and e... more Bulk heterojunction (BHJ) solar cells might one day play a vital role in realizing low-cost and environmentally benign photovoltaic devices. In this work, a BHJ solar cell was designed, based on a hexadeca-substituted phthalocyanine (FcPc) with ferrocenyl linked to the phthalocyanine ring. Next, we sought to obtain more quantitative information about the usability of this newly synthesized compound as a donor material in BHJ solar cells. Thus, BHJs with the structure of indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/FcPc:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend/LiF/Al were fabricated and characterized. The effect of blend ratio (0.5-2.0) on the BHJ solar cell parameters was also investigated. Interesting results were obtained in FcPc and the PCBM blend-based BHJ solar cell under optimized conditions. Our results presented here demonstrate that BHJ devices employing FcPc as a donor has great potential for the development of highly efficient no...
The recent advances in the synthesis of carborane and boronic ester-substituted tetrapyrroles (po... more The recent advances in the synthesis of carborane and boronic ester-substituted tetrapyrroles (porphyrins, porphyrazines, and phthalocyanines) are reviewed together with their possible utilization as agents for photodynamic therapy (PDT) and boron neutron capture therapy of cancer (BNCT) as well as dual PDT/BNCT sensitizers.
In this study, electrochemical behaviors of Co(II) and Pd(II) phthalocyanines carrying tetrakisdi... more In this study, electrochemical behaviors of Co(II) and Pd(II) phthalocyanines carrying tetrakisdiethoxymalonyl and Pd(II) phthalocyanine carrying tetrakiscarboxymethyl substituents at the peripheral positions are investigated by cyclic voltammetry and applied potential chronocoulometry techniques. Cyclic voltammetric studies show that, while Pd(II) phthalocyanines carrying diethoxymalonyl and carboxymethyl substituents give up to three common phthalocyanine ring reductions, Co(II) phthalocyanine carrying diethoxymalonyl substituents gives a
Magnesium porphyrazinate substituted with eight 4-tert-butylphenylthio-groups on the peripheral p... more Magnesium porphyrazinate substituted with eight 4-tert-butylphenylthio-groups on the peripheral positions has been synthesized by cyclotetramerization of 1,2-bis(4-tert-butylphenylthio)maleonitrile in the presence of magnesium butanolate. The metal-free derivative was obtained by its treatment with trifluoroacetic acid, and further reaction of this product with nickel(II) acetate led to the metal porphyrazinate (M = Ni). These new compounds have been characterized by elemental analysis, together with FT-IR, 1 H NMR and UV-Vis spectral data. The electronic properties of a spin coated film of NiPz have been studied by fabricating metal-insulator-semiconductor (MIS) capacitors. Current-voltage (I-V) and capacitancevoltage (C-V) measurements were carried out. It was observed that the Al/NiPz/p-Si structure exhibits rectifying behavior with a barrier height value of 0.89 eV and with an ideality factor value of 1.81. It was seen that this value of the obtained barrier height is remarkably higher than those given for metal/Si semiconductor contacts in the literature. The Lien, So and Nicolet method, combined with conventional forward I-V, was used to extract the series resistance value and it was found to be 26 kX. High frequency C-V measurements were used to determine the mobile oxide charge in the NiPz layer and this was found to be 1.6 Â 10 11 cm À2 .
Magnesium porphyrazinate substituted with eight (1-naphthylmethylthio) groups on the peripheral p... more Magnesium porphyrazinate substituted with eight (1-naphthylmethylthio) groups on the peripheral positions has been synthesized by cyclotetramerization of 1, 2-bis (1-naphthylmethylthio) maleonitrile in the presence of magnesium butanolate. The metal-free ...
Voltammetric and spectroelectrochemical characterization of the metallo-porphyrazines (M=2H+, Mg2... more Voltammetric and spectroelectrochemical characterization of the metallo-porphyrazines (M=2H+, Mg2+, Cu2+, Zn2+ and Co2+) substituted with eight (1-naphthylmethylthio) groups on the peripheral positions are described. Cyclic voltammetry and differential pulse voltammetry studies show that while metal-free, magnesium, zinc, and copper porphyrazine complexes give three ligand-based reductions and one ligand-based oxidation couple having diffusion controlled one-electron reversible character, cobalt porphyrazine gives both
Co(II) and Cu(II) complexes and metal-free t-butylphenyl peripherally substituted porphyrazine (P... more Co(II) and Cu(II) complexes and metal-free t-butylphenyl peripherally substituted porphyrazine (Pz) have been screened for in vitro antifungal (Aspergillus niger) and antioxidant (free radical scavenging, superoxide radical scavenging, and reducing power) activities. The results were compared with synthetic antioxidants, e.g., butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), trolox, or α-tocopherol. The free radical scavenging activity of H2Pz was higher than the CuPz
Novel, aryloxy-and arylalkyloxy-substituted pyrazine dicarbonitriles were synthesized from 5,6dic... more Novel, aryloxy-and arylalkyloxy-substituted pyrazine dicarbonitriles were synthesized from 5,6dichloropyrazine-2,3-dicarbonitrile and the corresponding phenol/alcohol derivatives. Cyclotetramerisation of these pyrazine derivatives to form metal pyrazinoporphyrazines in the presence of appropriate metal salts in different solvents such as DMF, quinoline, 2-dimethylaminoethanol and n-hexanol, resulted in decomposition products with the exception of teh latter solvent which lead to mainly octakis(alkyloxy) pyrazinoporphyrazines. Cyclic voltammetry and differential pulsed voltammetry of the complexes indicated that cobalt pyrazinoporphyrazine displayed both ligand and metal-based redox processes while zinc and copper derivatives exhibited only ligand-based redox processes. The redox processes of the pyrazinoporphyrazines shifted significantly towards positive potentials compared to those of the common phthalocyanines. The novel compounds were characterised using elemental analysis and spectral techniques.
A new phthalonitrile derivative bearing hexyloxy groups in the 3,6-positions and p-sulfonylphenox... more A new phthalonitrile derivative bearing hexyloxy groups in the 3,6-positions and p-sulfonylphenoxyand chloro groups in the 4 and 5-positions was synthesized. The new hexadeca-substituted zinc phthalocyanine was obtained by cyclotetramerisation of this phthalonitrile derivative in the presence of anhydrous zinc acetate under microwave heating. The aggregation behavior of the amphiphilic zinc phthalocyanine was studied in methanol and water. All novel compounds have been characterized by using elemental analysis, UVeVis, FT-IR, 1 H NMR and MS spectroscopic data. The photosensitizing activity of this phthalocyanine dye was evaluated by application of 1,3-diphenylisobenzofuran as a singlet oxygen chemical quencher. In cell culture media the phthalocyanine showed a cytotoxic effect on HepG2 cells; a feature which encourages future in vivo studies.
A pyrazinedinitrile derivative carrying dimethylaminoethylsulphanyl groups at positions 5 and 6 w... more A pyrazinedinitrile derivative carrying dimethylaminoethylsulphanyl groups at positions 5 and 6 was synthesised from 2-dimethylaminoethanethiol hydrochloride and 2,3-dicarbonitrile-5,6-dichloropyrazine. The dicarbonitrile gave magnesium azaphthalocyanine (MgAzaPc) when reacted with magnesium propoxide in propanol. The conversion of the MgAzaPc to a metal-free derivative was achieved by treatment with trifluoroacetic acid. Incorporation of transition metal ions into the inner core of azaphthalocyanine was accomplished by treatment of the metal-free derivative with metal acetates, i.e. Zn(OAc) 2 , Co(OAc) 2. These azaphthalocyanines were converted into water-soluble quaternised products by reaction with methyl iodide. Aggregation phenomena were followed for magnesium azaphthalocyanine with quaternisable dimethylamino substituents within a specific range of pH. The compounds were characterised by Fourier transform-infrared, proton nuclear magnetic resonance, mass and ultraviolet-visible spectral data.
Zeitschrift für anorganische und allgemeine Chemie, 2008
Porphyrazines, MPz (M = Mg, H, Ni, Zn and Co) with octakis 3‐methylbutylthio substituents have be... more Porphyrazines, MPz (M = Mg, H, Ni, Zn and Co) with octakis 3‐methylbutylthio substituents have been synthesized starting with the corresponding unsaturated dicarbonitrile derivative. These new compounds have been characterized by UV‐Vis, FT‐IR, 1H NMR, MS and elemental analysis methods. Voltammetric properties of the complexes were also investigated by CV, DPV and CPC techniques. Electrochemical studies show that three reversible one electron reductions and one reversible one electron oxidation processes (two for CoIIPz) are observed for all of the complexes. The E1/2 values are similar for the H2Pz, NiIIPz and ZnIIPz derivatives with negative shift due to the different effective nuclear charges of the central metal ion. Peak to peak separations and separation between the first reduction and first oxidation couples related with the HOMO‐LUMO gap of the complexes are in harmony with the common porphyrazine complexes.
ABSTRACT In this work, a new hexadeca substituted zinc phthalocyanine 4 bearing hexyloxy groups i... more ABSTRACT In this work, a new hexadeca substituted zinc phthalocyanine 4 bearing hexyloxy groups in non-peripheral positions and 3-(diethylamino)phenoxy groups in peripheral positions and its corresponding water-soluble octacationic derivative 5 have been reported. The new compounds have been characterized by elemental analysis, IR, UV, NMR and mass spectra. Zinc phthalocyanine showed excellent solubility in organic solvents of wide polarity range due to its amphiphilic nature and it enabled us to carry out detailed UV-Vis studies in different solvents. Octacationic zinc phthalocyanine 5 was soluble in DMF, DMSO and water. UV-Vis spectra of 5 in DMSO, DMF and water showed sharp Q band absorption as an indication of monomeric form even in aqueous media. This property of water-soluble non-aggregating zinc phthalocyanine is promising as a photosensitizer in Photodynamic Therapy of Cancer.
The focus of the present work is to gain more insight into the electrochemical behavior of newly ... more The focus of the present work is to gain more insight into the electrochemical behavior of newly synthesized Co II , Zn II , Cu II , and Pd II phthalocyanines with tetra-tricarbethoxyethyl substituents at the peripheral position. A more exhaustive electrochemical study of the complexes was done to determine the desired wisdom for the usage of the complexes as a functional material. A comparative study of the voltammetric measurements of these complexes showed that while Zn II , Cu II , and Pd II phthalocyanines exhibited up to four common phthalocyanine ring reductions, Co II phthalocyanine gave a metal-centered oxidation, a reduction and a ligand-centered reduction process. By contrast observation of the splitting of the second reduction process of Pd II phthalocyanine suggests aggregation of the complex. Diffusion coefficients of all complexes were determined by both the cyclic voltammetry and the potential step chronocoulometry techniques. Diffusion coefficients of the reduced and oxidized forms of the redox couples of the complexes were also calculated by the potential step chronocoulometry technique. Diffusion coefficients of the reduced forms of the electrode products of the complexes were found to be slightly higher than that of the oxidized forms.
ABSTRACT In this study, the syntheses and characterization of [2,3,7,8,12,13,17,18-octakis [2-(3-... more ABSTRACT In this study, the syntheses and characterization of [2,3,7,8,12,13,17,18-octakis [2-(3-quinolincarboxy)ethylhio] porphyrazinato (NNNN24)-N-21-N-22-N-23] magnesium(II), quaternized [2,3,7,8,12,13,17,18-octakis [2-(3-quinolincarboxy)ethylhio] porpyrazinato (NNNN24)-N-21-N-22-N-23] magnesium(II), [2,3,7,8,12,13,17,18-octakis[2-(3-quinolinecarboxy)-ethylthio]21H23H (NNNN24)-N-21-N-22-N-23 porphyrazine and [2,3,7,8,12,13,17,18-octakis[2-(3-quinolinecarboxy)-ethylthio]porphyrazinato (NNNN24)-N-21-N-22-N-23} zinc are described. The new compounds have been characterized by elemental analysis, FT-IR, H-1-NMR, and mass spectra. General trends are described for fluorescence quantum yields of these compounds in dimethylsulfoxide (DMSO). In this study, the effects quaternization of the substituents on the photophysical and spectroscopic properties are also reported.
Bis(3-methylbutantio) maleonitril has been obtained from the reaction of disodium salt, 1-bromo-3... more Bis(3-methylbutantio) maleonitril has been obtained from the reaction of disodium salt, 1-bromo-3 methylb ü tan in acetone under nitrogen for 11 hours. MgPz has been synthesized through the cyclotetramerization reaction of magnesium and n-butanol with bis(3-methylbutantio) maleonitril. The metal free pophyrazine derivative was obtained by its treatment with trifluroacetic acid and further reaction of this product with cobalt(II) acetate, nickel(II) acetate and zinc(II) acetate led to the metal porphyrazine (MPz, M = Co, Ni ve Zn). These new compounds have been investigated and characterized by UV, FT-IR, 1 H NMR, GC-MS and elemental analysis methods.
Thin films of tetra (tricarbethoxy)-substituted metallophthalocyanines [where the metal was Cobal... more Thin films of tetra (tricarbethoxy)-substituted metallophthalocyanines [where the metal was Cobalt(II), Copper(II) or Palladium(II)] were prepared by spin coating technique. Optical properties of thin films were investigated by measuring the transmittance and reflectance using a spectrophotometer in the wavelength range of 350-1000 nm. The refraction index and extinction coefficient were determined. Surface microstructure of the films was observed by Atomic force microscopy. Also, the optical band gap and dielectric constant values were calculated.
The adsorption of [octakis(2-trimethylammoniumethylsulfanyl)-porphyrazinatocobalt]octaiodide from... more The adsorption of [octakis(2-trimethylammoniumethylsulfanyl)-porphyrazinatocobalt]octaiodide from aqueous solution onto negatively charged sepiolite is investigated. The effects of temperature, dye and solid concentration and contact time on adsorption were evaluated. Adsorption experiments were analyzed in the light of zeta potential measurements and desorption behavior of the dyeesepiolite composite. Experimental data were analyzed using four adsorption kinetic models, of which a pseudosecond-order kinetic model was found to be superior. Experimental equilibrium data were fitted to five adsorption isotherm models, from which the free energy, enthalpy and entropy of the adsorption processes were determined. Adsorption onto sepiolite was exothermic and spontaneous. AAS and FTIR were used to elucidate the adsorption mechanism. The novel composite is considered to be useful in optical and catalytic applications.
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