Electrochemical and in situ spectroelectrochemical investigations into the redox and aggregation behaviours of phthalocyanines bearing octyl 4-phenyloxyacetate moieties

2010 ◽  
Vol 88 (4) ◽  
pp. 375-382 ◽  
Author(s):  
İmran Koç ◽  
Meryem Çamur ◽  
Mustafa Bulut ◽  
A. Riza Özkaya
Keyword(s):  
Cobalt Complex ◽  
Differential Pulse ◽  
Redox Processes ◽  
Tetrabutylammonium Perchlorate ◽  
Pulse Voltammetry ◽  
The Difference ◽  
Electron Reduction ◽  
Aggregation Phenomenon ◽  
Aggregation Phenomena

Electrochemical and spectroelectrochemical properties of phthalocyanines (H2Pc, ZnPc, NiPc, CuPc, and CoPc) involving octyl 4-phenyloxyacetate moieties have been investigated by cyclic voltammetry and differential pulse voltammetry on Pt in dimethylsulfoxide – tetrabutylammonium perchlorate. These measurements showed that the complexes undergo subsequent one-electron reduction and oxidation processes. In situ UV–vis spectroelectrochemical measurements enabled us to identify the ligand- and metal-based redox processes, and evaluate the effect of aggregation phenomena on these processes. The cobalt complex showed both metal-based and ring-based one-electron redox processes, while the other complexes displayed only ring-based one-electron couples. It was observed that the redox processes of H2Pc, NiPc, and CuPc are coupled by aggregation phenomenon, whereas those of ZnPc and especially CoPc are not, probably owing to the difference in their axial coordinating properties.

Electrochemical and in situ spectroelectrochemical behavior of 2,3,7,8,12,13,17,18-octakis(hexyl-thio) tetraazaporphyrin (H2OHTTAP) and [Zn(II)OHTTAP]

2001 ◽  
Vol 05 (06) ◽  
pp. 523-527 ◽  
Author(s):  
YANXIU ZHOU ◽  
ZHENXING WANG ◽  
DAIKE WANG ◽  
KENICHI SUGIURA ◽  
YOSHITERU SAKATA
Keyword(s):  
Electron Transfer ◽  
Differential Pulse ◽  
Single Electron ◽  
Single Electron Transfer ◽  
Free Base ◽  
Cation Radicals ◽  
Pulse Voltammetry ◽  
Electron Reduction

The characterization of free base porphyrin 2,3,7,8,12,13,17,18-octakis(hexyl-thio) tetraazaporphyrin (H2OHTTAP) and its zinc(II) complexes [ Zn (II)OHTTAP] containing eight thioether groups at the β-pyrrole positions of the macrocycle was reported. Results obtained by cyclic voltammetry and differential pulse voltammetry indicated a five-electron reduction in five steps for each complex. They were oxidized in two single-electron-transfer steps to yield π-cation radicals and dications and reduced in three single-electron-transfer steps to yield π-anion radicals, dianions and trianions, respectively. The redox property of H2OHTTAP was unusual as compared to porphyrins (PPs) and phthalocyanines (Pcs). Each process was monitored by in situ thin-layer spectroelectrochemistry, which indicated that only the ligand was electroactive. The existence of the eight hexylthio groups was responsible for the intrastack interactions and enhanced intracolumnar and intercolumnar electron motions, resulting in improved conductivity.

scholarly journals Synthesis and electrochemical characterization of substituted indolizine carboxylates

2013 ◽  
Vol 78 (6) ◽  
pp. 827-838 ◽  
Author(s):  
Maria-Laura Soare ◽  
Eleonora-Mihaela Ungureanu ◽  
Emilian Georgescu ◽  
Liviu Birzan
Keyword(s):  
Cyclic Voltammetry ◽  
Differential Pulse Voltammetry ◽  
Electrochemical Behaviour ◽  
Substituent Effects ◽  
Detailed Comparison ◽  
Differential Pulse ◽  
Synthesis And Characterization ◽  
Redox Processes ◽  
Pulse Voltammetry

This work is devoted to the synthesis and characterization of new indolizine derivatives. Particular attention was paid to the electrochemical investigations by cyclic voltammetry and differential pulse voltammetry. The redox processes for each compound were established, analyzed and assessed to the particular functional groups at which they take place. This assessment was based on detailed comparison between the electrochemical behaviour of the compounds, similarities in their structure, as well as substituent effects.

Electrochemistry of homoleptic bis[3(4),12(13),21(22),30(31)-tetra(tert-butyl)-naphthalocyaninato] rare earth(III) complexes

2005 ◽  
Vol 09 (01) ◽  
pp. 40-46 ◽  
Author(s):  
Renjie Li ◽  
Xianxi Zhang ◽  
Na Pan ◽  
Peihua Zhu ◽  
Nagao Kobayashi ◽  
...  
Keyword(s):  
Differential Pulse ◽  
Electrochemical Characteristics ◽  
Redox Potentials ◽  
Separation Effect ◽  
Tert Butyl ◽  
Double Decker ◽  
Half Wave ◽  
Pulse Voltammetry ◽  
The Difference ◽  
Order Comparison

The electrochemistry of homoleptic bis(naphthalocyaninato) double-decker complexes for the whole series of tervalent rare earths M ( TBNc )2 ( M = Y , La … Lu except Ce and Pm ; H 2 TBNc = 3(4),12(13),21(22),30(31)-tetra(tert-butyl)naphthalocyanine) has been systematically studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Up to three quasi-reversible one-electron oxidations and four quasi-reversible one-electron reductions have been revealed for these double-deckers.The half-wave potentials of all oxidations and the first reduction for double-decker complexes are dependent on the size of the metal center. The difference between the redox potentials of the first and second reductions for M III( TBNc )2, which represents the potential difference between the first oxidation and first reduction of [ M III( TBNc )2]−, lies in the range 1.09-0.95 V and gradually diminishes along with the lanthanide contraction, indicating increased π-π interaction in the double-deckers in the same order. Comparison of electrochemical characteristics between M ( TBNc )2 and M ( TBPc )2 ( H 2 TBPc = 2(3),9(10),16(17),24(25)-tetra(tert-butyl)-phthalocyanine) reveals that extension of the ligand conjugated system upon going from phthalocyanine to naphthalocyanine attenuates the ring-to-ring separation effect on the redox potentials of the double-deckers of the whole series of tervalent lanthanides.

Electrically stimulated liquid phase microextraction combined with differential pulse voltammetry: a new and efficient design for in situ determination of clozapine from complicated matrices

RSC Advances ◽  
2016 ◽  
Vol 6 (16) ◽  
pp. 12943-12952 ◽  
Author(s):  
Ahmad Rouhollahi ◽  
Masoomeh Kouchaki ◽  
Shahram Seidi
Keyword(s):  
Liquid Phase ◽  
Differential Pulse Voltammetry ◽  
Differential Pulse ◽  
Efficient Design ◽  
Liquid Phase Microextraction ◽  
Electromembrane Extraction ◽  
Pulse Voltammetry ◽  
Complicated Matrices

Electromembrane extraction combined with differential pulse voltammetry for in situ determination of clozapine from complicated matrices.

scholarly journals Electrochemical monitoring of a photocatalytic desulfurization process of a model liquid fuel

2019 ◽  
Vol 9 (2) ◽  
pp. 73-78
Author(s):  
Lina Marcela López-Lozano ◽  
Cesar Augusto Quiñones-Segura ◽  
Oscar Rodríguez-Bejarano
Keyword(s):  
Uv Light ◽  
Supporting Electrolyte ◽  
Differential Pulse ◽  
Model Liquid ◽  
Desulfurization Process ◽  
Experimental Works ◽  
Pulse Voltammetry ◽  
Model Oil ◽  
Electrochemical Monitoring

Thiophene is a sulfur compound found mostly in gasoline and contributor to air pollution. This paper analyzes UV light photocatalytic desulfurization of model oil using Ag/TiO2. Thiophene concentration in the oil phase was determined by the electrochemical analyzer using Differential Pulse Voltammetry (DPV). The electrochemical experimental works were performed by two methodologies. First, aliquots of the oleic mixture were taken every 30 minutes and the thiophene concentration was measured over 7 hours of degradation. The concentration of thiophene decreased by 37.94%. In the second methodology, the in situ thiophene concentration was determined by DPV, where the reaction mixture was altered by the addition of acetonitrile and a quaternary ammonium salt as solvent-supporting electrolyte system. In this medium, the thiophene concentration was reduced by 43.88% after 4 hours of photocatalytic degradation.

Synthesis and electronic properties of acetylene- and butadiyne-linked 3,3′-porphycene dimers

2014 ◽  
Vol 18 (10n11) ◽  
pp. 849-855 ◽  
Author(s):  
Takuya Okabe ◽  
Daiki Kuzuhara ◽  
Naoki Aratani ◽  
Hiroko Yamada
Keyword(s):  
Fluorescence Spectra ◽  
Electrochemical Measurement ◽  
Differential Pulse ◽  
X Ray Diffraction ◽  
Reduction Potentials ◽  
Oxidation Potentials ◽  
The Common ◽  
Pulse Voltammetry ◽  
Electron Reduction ◽  
C Nmr

The butadiyne- and acetylene-linked 3,3′-porphycene dimers 1 and 2 were synthesized from the common intermediate, 3-ethynyl-2,7,12,17-tetrahexylporphycene 4. The butadiyne-linked dimer 1 was prepared from 4 by copper mediated Glaser-type homo-coupling. The acetylene-linked dimer 2 was synthesized by Sonogashira coupling of 4 and 2,7,12,17-tetrahexyl-3-iodoporphycene 5. These porphycene dimers were characterized by 1 H and 13 C NMR spectroscopies, mass spectroscopy, X-ray diffraction analysis, UV-vis absorption and fluorescence spectra, cyclic voltammetry and differential pulse voltammetry. Crystal structure of 1showed a coplanar structure of two porphycene units. The absorption spectra in CH 2 Cl 2 indicated the small interaction between the porphycene units through the linkage at 3,3′-positions. The electrochemical measurement showed two one-electron oxidation potentials and four one-electron reduction potentials indicating the electric interaction between the porphycene units.

Sign in / Sign up

Export Citation Format

Share Document