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A novel class of copolyesters containing the metallophthalocyanine ring [M-Pc, M=Fe(III), Co(II)] in the chain was synthesized by polycondensation of (dicarboxyphthalocyaninato) metal [M-Dapc, M=Fe(III), Co(II)] diacid chloride, terephthalic acid chloride and aliphatic diols. The structures of the copolyesters were characterized by infrared, electronic as well as ESR spectra, and viscosity measurement. The thermal stabilities of the polymers were evaluated by dynamic thermogravimetric analyses. The polymers obtained thus were easily soluble in chloroform, dichloromethane, etc. The green or blue colored fiber was formed by melt spinning of the copolyesters containing below 1 mol % M-Pc component. The copolyester containing Co(II)-Pc in the chain obtained from 1,2-ethanediol as a diol component catalysed the autoxidation of 2-mercaptoethanol in the presence of oxygen.

Cobalt phthalocyanine (Na_2.8CoPc) organic molecular ferromagnets with a Curie temperature higher than room temperature were synthesized. By means of EXAFS spectroscopy the nearest coordinational environment of the Co ion was examined in both Na_2.8CoPc and pristine β-CoPc as well as in standard substances containing metallic cobalt. The nearest coordinational environment of the Co ion in ferromagnetic Na_2.8CoPc is shown to remain virtually invariable as compared with that in pristine β-CoPc. This environment is conditioned by the nitric and carbonic coordination spheres of the phthalocyanine and differs essentially from the nearest coordinational environment of Co in metallic cobalt. The results of EXAFS studies serve as direct structural evidence that the nature of the ferromagnetism in Na_2.8CoPc is conditioned by the organic matrix, namely by (CoPc)²⁻ and (CoPc)³⁻ anions with unpaired π-electrons in the 7e_g doubly degenerate MO of the conjugated phthalocyanine macro-ring.

The kinetics of the oxidative destruction of cobalt phthalocyanine derivatives in aqueous solutions has been investigated in the concentration interval 10⁻⁴–10⁻⁵M as a function of the concentration of alkali and the partial pressure of oxygen in the system. The kinetic equation for the initial solution bleaching rate is obtained. A mechanism of cobalt phthalocyanine destruction involving an intermediate Co(II) → Co(III) oxidation step is suggested.

Products based on metal phthalocyanines are widely used in industry. In the processing of these materials it is essential to control the conditions of the matrix the metal phthalocyanines are embedded in. Using the example of cobalt(II) phthalocyanine in sulfuric acid we show that continuous wave and pulse electron paramagnetic resonance and electron nuclear double resonance spectroscopy provide excellent tools to monitor the influence of the matrix on paramagnetic phthalocyanines. The g values, the cobalt hyperfine values, and the hyperfine and nuclear quadrupole couplings of the isoindole nitrogens, as well as the hyperfine interactions of the surrounding protons allow for a detailed assessment of the electronic structure of cobalt(II) phthalocyanine in sulfuric acid. Subtle differences between the system under study and related Co(II) porphyrin and corrin systems could be traced.

Cobalt (4) and iron (5) phenylthio-substituted phthalocyanines (MPc(SR)₈) have been synthesized and characterized. Cyclic square wave voltammetry in dimethylformamide containing tetrabutylammonium perchlorate revealed five and six redox processes, respectively, for complexes 4 and 5. The complexes are easier to reduce compared to the corresponding unsubstituted MPc and to butylthio substituted derivatives. The first oxidation and reduction occurs on the metal for both complexes. Spectroelectrochemistry (in dimethylformamide containing tetrabutylammonium perchlorate) was employed to assign the cyclic voltammetry peaks, and gave spectra characteristic of Fe^IPc for reduction of 5 and Co^IPc for the reduction of 4. The spectrum of the former is particularly of importance since such species have not received much attention in the literature.

Cobalt phthalocyanine (CoPc), cobalt tetracarboxy phthalocyanine (CoTCPc) and cobalt octacarboxy phthalocyanine (CoOCPc), adsorbed onto glassy carbon electrodes, have been used for the electrocatalytic detection of nitrite, L-cysteine and melatonin. The modified electrodes electrocatalytically detected nitrite around 800 mV vs.Ag|AgCl, a value less positive compared to that of an unmodified glassy carbon electrode (at 950 mV vs.Ag|AgCl) and also gave detection limits in the 10^-7 M range for nitrite detection. L-cysteine was detected by the modified electrodes at potentials between 0.50 to 0.65 V vs.Ag|AgCl, with L-cysteine detection limits also in the 10^-7 M range. The detection limits for melatonin ranged from 10^-7 to 10^-6 M. CoPc-modified electrodes displayed good separation of interferents (tryptophan and ascorbic acid) in the presence of melatonin. Analyses of commercial melatonin tablets using modified electrodes gave excellent agreement with manufacturer's value for all modified electrodes of this work.

Neutral cobalt(II) phthalocyanine and 2,3- and 3,4-tetrapyridoporphyrazine complexes were examined in pyridine, dimethyl sulfoxide and N,N-dimethylformamide to evaluate their catalytic properties in the reductive dechlorination of 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (p,p'-DDT). Cyclic voltammetry, controlled potential bulk electrolysis and thin-layer UV-visible spectroelectrochemistry of each compound in the presence of DDT indicated that both the singly and doubly reduced species, [Co(I)]^- and [Co(I)]^2-, can catalyze the dechlorination of DDT through the formation of, and a photoinduced or electrochemically induced cleavage of, the Co-C bond in the organometallic intermediates. GC-MS analysis revealed that DDT was converted to 1,1-bis(4-chlorophenyl)-2, 2-dichloroethane (p,p'-DDD), 1,1-bis(4-chlorophenyl)-2,2-dichloroethylene (p,p'-DDE) and 1,1-bis(4-chlorophenyl)-2-chloroethylene (p,p'-DDMU), upon dechlorination. The catalytic performance of the three cobalt complexes depends upon the reactive nature of each compound, the solvent, the reaction time and the equivalence of DDT. In addition, either DDD or DDE can be catalytically dechlorinated to generate DDMU, possibly through a similar mechanism.

This work demonstrated preparation, characterization, and application of a cobalt phthalocyanine based enzymeless/mediatorless hydrogen peroxide sensor. The cobalt phthalocyanine (CoPc) was retained in polyaniline (PANI) film on a glassy carbon electrode during electrochemical polymerization of aniline and consequently a novel composite electrode (GCE/PANI/CoPc) for the electrochemical sensor application was constructed. The CoPc functionalized composite electrode, GCE/PANI/CoPc, was evaluated by voltammetry, electrochemical impedance spectroscopy, and UV-vis spectroscopy. The results displayed retaining of the CoPc molecules in the PANI film on the GCE electrode. Presence of CoPc in PANI increased conductivity of the composite on the electrode. Sensing performance of the GCE/PANI/CoPc composite electrode to H₂O₂ were evaluated in detail with respect to the selectivity, reproducibility, repeatability, stability, linear concentration range, and sensitivity with voltammetric and double potential step chronoamperometric techniques. The GCE/PANI/CoPc composite electrode gives a linear range for H₂O₂ between 2 and 18 μM H₂O₂ with sensitivities of 1.55 A.M^-1 during the cathodic SWV scan and with sensitivities of 4.01 A.M^-1 during the anodic SWV scan. A direct application of the sensor was performed in a real working condition, for the detection of hydrogen peroxide produced from the reaction between the glucose and glucose oxidase enzyme.

Electrocatalytic properties of cobalt phthalocyanine (CoPc), cobalt tetra-carboxy phthalocyanine (CoTCPc) and cobalt octa-carboxy (CoOCPc), towards the detection of dicrotophos have been studied. Catalytic behavior towards the reduction of dicrotophos was found to be dependent on the pH, as well as the substitution on the phthalocyanine ring. Strong electron withdrawing groups on the phthalocyanine ring yielded best catalysis as evidenced by the enhancement of the reduction peak current, (~5 fold) compared to the bare glassy carbon electrode. The analysis gave a good detection limit of 1.25 × 10^-7 M, and good linearity for the studied concentration range. A high Tafel slope value was obtained, indicating a strong interaction between dicrotophos and the cobalt phthalocyanine complex.

Hexadecasubstituted CoPc and ZnPc containing different number of N-methylpyridiniumoxy groups and chlorine atoms were synthesized. It was shown that increasing number of cationic groups leads both to increased solubility of complexes in dipolar aprotic organic solvents and in water, and to increased contribution of monomeric form in aggregation equilibrium in water up full disaggregation.

Cobalt(II) phthalocyanine has been encapsulated into the supercage of X-type zeolite as an active monomer (CoPc-X) by the "ship-in-bottle" synthesis method, and furthermore the CoPc-X has been ion-exchanged with secondary metals (Mⁿ⁺ = Na⁺, Ag⁺, Cu²⁺, Zn²⁺) to obtain CoPc-Mⁿ⁺-X. They have been characterized by elemental analysis, fluorescent X-ray, UV-vis, diffuse reflectance, physisorption analysis, and ESR spectroscopic methods, and their deodorant behaviors for smell gasses, 2-nonenal and indole, have been examined.

Phthalocyanines (Pcs) have been known for excellent electron transfer properties owing to their extended $\pi$-conjugated structures. In addition, functionalized iron oxide nanoparticles (Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$ NPs) have attracted considerable interest owing to their unique spectral and electronic properties. Hence, it can be reasonably expected that Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$ NPs decorated with Pc molecules could provide a useful electrocatalytic system. Herein, we present the preparation and electrochemical properties of cobalt-phthalocyanine (CoPc)-decorated Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$ NPs (CoPc@Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}})$. The Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$ NPs were first coated with a silica layer to produce SiO${}_{\mathrm{\text{2}}}$@Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$. Subsequently, CoPc with a siloxane end group (CoPc-TEOS) was anchored to the outer surface of the SiO${}_{\mathrm{\text{2}}}$@Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$. The CoPc@Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$ thus prepared was fully analyzed using various characterization methods. Distinctive electrochemical responses of CoPc and CoPc@Fe${}_{\mathrm{\text{3}}}$O${}_{\mathrm{\text{4}}}$ in the presence of picric acid were observed, demonstrating the potential application of the current approach to electrochemical catalysis.

Dimethyl disulfide (DMDS) is an important fine chemical that can be prepared by the refined Merox process of oxidation of sodium methyl mercaptide (SMM) in the presence of a catalyst. In this paper, a novel activated carbon (AC) supported cobalt(II) tetraaminophthalocyanine (AC-CoTAPc) catalyst was prepared by the chemical grafting method. EA, UV-vis, FT-IR, BET and XPS were used to characterize the structure of the new catalyst. The effects of reaction time, catalyst dosage, reaction temperature and oxygen pressure on SMM conversion per pass (CPP${}_{SMM})$, yield (Yield${}_{DMDS})$ and purity of DMDS product (Purity${}_{DMDS})$ were investigated to evaluate the catalytic performance of new AC-CoTAPc catalyst. The results show that free CoTAPc is easily dissolved in this DMDS product, which needs extra post treatment and cannot be reused. The supported catalyst AC-CoTAPc can easily solve these problems and can be properly reused four times to get Yield${}_{DMDS}$ and CPP${}_{SMM}$ higher than 70% and 90%. Under optimum conditions, the Yield${}_{DMDS}$ andCPP${}_{SMM}$ of the AC-CoTAPc catalyst could be as high as 87.4% and 98.1%, with a purityof DMDS product of above 99.9%. AC-CoTAPc exhibits better catalytic and reuse performance than the commercial AC-supported sulphonated cobalt(II) phthalocyanine (AC-CoPcS) catalyst and shows broad industrial application prospects.

This work describes the adsorption of synthesized cobalt mono (CoPc) and binuclear phthalocyanines (CoBiPc) with single walled carbon nanotubes (SWCNT) to form SWCNT-CoPc or SWCNT-CoBiPc as non-covalent conjugates onto glassy carbon electrodes (GCE). The cobalt complexes and their SWCNT-conjugate-modified electrodes were studied for their electrocatalytic oxidation towards 4-chlorophenol. All modified electrodes showed improved catalytic current and stability towards the detection of 4-chlorophenol. The best activity was observed for the SWCNT-CoBiPc2 system in terms of current response and the SWCNT-CoBiPc1 system in terms of resistance to electrode fouling.

This work describes the adsorption of synthesized cobalt mono (CoPc) and binuclear phthalocyanines (CoBiPc) with single walled carbon nanotubes (SWCNT) to form SWCNT-CoPc or SWCNT-CoBiPc as non-covalent conjugates onto glassy carbon electrodes (GCE). The cobalt complexes and their SWCNT-conjugate-modified electrodes were studied for their electrocatalytic oxidation towards 4-chlorophenol. All modified electrodes showed improved catalytic current and stability towards the detection of 4-chlorophenol. The best activity was observed for the SWCNT-CoBiPc2 system in terms of current response and the SWCNT-CoBiPc1 system in terms of resistance to electrode fouling.