Mehmet Kandaz

Synthesis, characterization and electrochemistry of novel differently octasubstituted phthalocyanines

Abstract We describe the complete synthesis of differently substituted multifunctional metallo phthalocyanines (MPcs) (M=Ni, Zn, Co) bearing four 2′-aminophenylsulfanyl or 2-aminophenoxy moieties and four chloro atoms on peripheral positions. The synthesis started from the corresponding anhydrous metal salts and differently substituted [4-(2′-aminophenylsulfanyl)-5-chlorobenzene-1,2-dicarbonitrile] (2a) and [4-(2-aminophenoxy)-5-chlorobenzene-1,2-di-carbo nitrile] (2b), and the products were separated by HPLC. These multifunctional amino substituents serve as strong binding sites for further reactions after phthalocyanine formation, such as Schiff-bases, and provide solubility of the phthalocyanines in organic solvents (THF, CHCl3 and CH2Cl2). The newly synthesized compounds have been characterized by elemental analysis, FTIR, 1H NMR, MS (EI and FAB), UV–Vis and atomic absorption spectroscopy. Electrochemical studies reveal that CoPc (6a) has two metal and four ligand-based redox processes while NiPc (4a) and ZnPc (5b) show three ligand-based reduction processes.

Synthesis, spectroscopy and redox properties of a novel (E–E) vic-dioxime and its mono-, di- and trinuclear complexes bearing an 18-membered N2O2S2 macrocyle

Abstract A new 18-membered ligand, 2,3-dibromo-6,7,13,14,15,16,22,23-octahydro 14, 15-bis(hydroxyimino)-tribenzo [e,k,q] [1,4,10,13,7,16] diazadioxadithiacyclooctadecine (LH4) containing three different heteroatoms (N, O, S) has been prepared from 1,2-bis (2′-amino phenylsulfanylethoxy)-4,5-dibromobenzene and cyanogen di-N-oxide. Mononuclear (LH3)2M, where M=Ni(II), Cu(II), Co(II), Fe(II) binuclear (LH)2(UO2)2(OH)2 and trinuclear (LH)2M3, where M=Cu (II), Co (II) complexes of LH4 have been obtained with a metal:ligand ratio 1:2, 2:2 and 3:2, respectively, through N,N-coordinating or N, N, S, S-coordinating in the presence of a base, as do most of the vic-dioximes. 1H NMR, IR, UV–Vis and MS data are presented. The cyclic voltammetric (CV) measurements of the newly synthesized compounds were measured. Voltammetric results showed that oxime-containing ligands stabilize Ni(III), Fe(III), Co(III) and Cu(III). The Fe(II) complex displayed a different behavior with respect to other complexes. This indicated that both Fe(III) and Fe(I) species are stable while oxime containing ligands tend to stabilize only one of the oxidized forms of the metal center of the complexes. Differently, ligand based reduction was recorded only with the Ni(II) complex.

Synthesis and characterization of novel symmetrical phthalocyanines substituted with mono- or bi-macrocycles

Abstract A new generation of soluble metallophthalocyanine derivatives (5a, 5b, 6a, 6b, 7b, 8b and 8b·2KSCN) bearing four 14-membered [1,4,8,11] dioxadiaza macrocycles, 14-membered [1,4,8,11] diazadithia-macrocycles or 14-membered [1,4,8,11] diazadithia-macrocycles fused to a 15-membered crown-ether have been prepared by cyclotetramerization of the newly synthesized dicyano macrocycle (3a, 3b and 4b) in the presence of appropriate metal salts in non-aqueous solvents. The N-tosylated derivatives are extensively soluble in apolar solvents. The interaction of the alkaline metal salts with the crown-ether groups of the complex 8b resulted in products of less solubility. Elemental analysis results and IR, UV–Vis, 1H NMR, mass spectral data on the newly synthesized intermediates and all phthalocyanines are in accordance with the proposed structures.

Functional solitare- and trans-hybrids, the synthesis, characterization, electrochemistry and reactivity of porphyrazine/phthalocyanine hybrids bearing nitro and amino functionality

We report here for the first time a new and improved approach to the complete synthesis and characterization of the unsymmetrical metallo- and metal-free phthalocyanine/porphyrazine (Pz/Pc) hybrids bearing peripheral nitro or amine functionality, H2[Pz(n-Pr)6(BzNO2)] or H2[Pz(n-Pr)4(BzNO2)2], where Bz = benzo, n-Pr = n-propyl, fused on the one or two benzenoid ring which form from the reaction of two different precursors, 3,4-bis-(n-propyl)-pyroline-2,5-diimine and 6/7-nitro-1,3,3-tricholoro isoindoline, with the base-catalyzed direct condensation method. The direct condensation method used in this study enable us to skip magnesium porphyrazine (MgPz) stage and limits the formation of undesired hybrid compounds when compared with cross-condensation method. Centrally metallated solitare- and trans-Pz/Pc hybrids, M[Pz(n-Pr)6(BzNO2)] or M[Pz(n-Pr)4(BzNO2)2](M = Zn(II) or Mn(II)), synthesized in this study are somewhat more soluble than the free ones. Metallo Pz/Pc hybrids were prepared by treatment of free-soitare and trans hybrids with the appropriate metal salts in anhydrous solvent mixtures. We observed that the solubility of solitare- and/or trans-Pz/Pc hybrids increases after nitro-substituted Pz/Pc hybrids are reduced to amine substituted ones. The reactivity of the NH2 group of the solitare-Zn[Pz(n-Pr)6(BzNH2)] was tested by the condensation with ferrocenecarboxyaldehyde resulting in the formation of the ferrocene-substituted hybrid. The newly synthesized compounds have been characterized by elemental analaysis, FT IR, 1H NMR, UV-vis and MS spectroscopy. Electrochemical measurements of the complexes characterized in this study showed that the attachment of NO2 and NH2 moieties at the periphery makes a monitorable effect on redox properties of the macrocycle and metal center.

Synthesis and Electrochemistry of Soluble Phthalocyanine Complexes Containing Four Peripheral Dihexyl and Dihexylhexylmalonate Residues

Summary. Tetrasubstituted phthalocyanines bearing four dihexylmalonate or dihexylhexylmalonate residues on the periphery (M[Pc(CH(COOC6H13)2)4] or M[Pc(C(COOC6H13)2 C6H13)4]; M = Pd(II), Cu(II), Co(II)) were synthesized from the anhydrous metal salts and the corresponding phthalonitriles. The complexes were only slightly soluble in polar solvents such as methanol and ethanol, but more soluble in less polar solvents such as benzene, toluene, and even hexane. The spectroscopic properties of the complexes were affected strongly by the electron withdrawing malonate units. Cyclic voltammetry on a platinum electrode in dichloromethane showed ligand-based one-electron transfers for Cu and Pd compounds, whereas the Co complex displayed metal-based or/and ligand-based one-electron transfers depending on the supporting electrolyte anion. The structures were confirmed by elemental analysis, 1H NMR, 13C NMR, IR, mass (EI and FAB), and UV/Vis spectroscopy.

Synthesis and Properties of Copper(II) Phthalocyanines with Monoazacrown and Crown Ethers as Peripheral Substituents

Soluble and less soluble phthalocyaninatocopper(II) derivatives (4a and 4b) were prepared from the corresponding 7-[(4′-benzo-15-crown-5)oyl]-15, 16-dibromo-2,3,6,7,8,9,11,12-octahydro-5H-benzo[e]-[1,4,10,13,7] tetraoxaazacyclopentadecine (3a) and 7-(2′-tosylaminoethyl)-15, 16-dibromo-2,3,6,7,8,9,11, 12-octahydro-5H-benzo[e]-[1,4,10,13,7] tetraoxaazacyclopentadecine (3b) and CuCN in pyridine. A less soluble novel multifunctionalized scorpiand macrocycle-substituted phthalocyanine (4c) in which an NH2CH2CH2— chain is appended to a monoazacrown ether ring was obtained by detosylation of 4b with concentrated sulfuric acid.

Functional alcohol-soluble double-decker phthalocyanines: synthesis, characterization, electrochemistry and peripheral metal ion binding

In this study we report the preparation, physical characterization and electrochemistry of peripherally functionalized substituted ionophore double-decker lanthanide phthalocyanines, lanthanide bis-[(4,4″,4″,4‴)-tetrakis-(6-hydroxyhexylthio)phthalocyaninates], {M[Pc(S-C6H13OH)4]2} (M = PrIII, YbIII, and LuIII). All benzenes on the double-decker phthalocyanines are functionalized with hydroxyhexylsulfanyl moieties for potential use as metal ion binding and surface anchors. The double-decker phthalocyanines synthesized from the anhydrous metal salts {Ln(acac)3} and the corresponding 4-(6-hydroxyhexylthio)-1,2-dicyanobenzene exhibit ion-specific optical changes in the presence of Ag+ and Pd2+. Thio donors of the complexes coordinate to Ag+ and Pd2+ to give 4:1 metal-phthalocyanine complexes. Newly synthesized lanthanide double-decker phthalocyanines are soluble in methanol (MeOH), ethanol (EtOH), tetrahydrofuran (THF), dimethylformamide (DMF), dimethylsulfoxide (DMSO), chloronapthalene, quinoline and less soluble in i-PrOH and acetonitrile. Electrochemical studies reveal that all lanthanide-base complexes undergo ligand-based redox processes. The smaller HOMO-LUMO gaps of the complexes indicate the existence of strong π-orbital interactions between the rings of the sandwich. The newly synthesized compounds have been characterized by elemental analysis, FTIR, 1H and 13C NMR, MS (ESI and Maldi-TOF), UV-vis and EPR spectral data.

A novel (E,E)-dioxime and its mono-, di- and trinuclear complexes bearing tetradentate octyl sulfanyl phenylamino substituents. Synthesis, characterization and electrochemical properties of its transition metal complexes

A new vic-dioxime, 13,14-bis-(hydroxyimino)-9,12,15,18-diazadithiaoctacosane, has been synthesized from 2-octylsulfanylaminobenzene and (E,E′)-dichloroglyoxime. Mononuclear transition metal complexes of NiII, CuII, CoII and FeII have been prepared and were found to have a metal–ligand ratio of 1:2. The synthesis of di- and trinuclear complexes was achieved with UIVO2 and CuII depending on the stoichiometry of the reactants. The complexes were characterized by elemental analysis, 1H-n.m.r., u.v.–vis, i.r., f.a.b.-m.s. and by cyclic voltammetry.

Both alcohol and halogenated solvents soluble soft-metal sensor functional phthalocyanines: synthesis, electrochemistry, spectroelectrochemistry

In this study, we report a novel both alcohol and haloganated solvent soluble selective ionophore functional ligand and its β-substituted 2(3),9(10),16(17),23(24)-tetrakis(1-hydroxyhexan-3-ylthio)-phthalocyanines, M{Pc[S-CH(CH2CH2CH3)(CH2CH2OH)]4}, (Pc: Phthalocyanine) (M = Zn, Cu, Co), where -OH indicates peripheral functionality. Pcs exhibiting both hydrophobic and hydrophilic character were characterized spectroscopically (FT-IR, 1H and 13C NMR, MS (MALDI-TOF) and UV-vis), electrochemically and spectroelectrochemically. The complexes were soluble in both polar solvents, such as MeOH and EtOH, and non-polar solvents such as CHCl3, CH2Cl2, benzene, toluene, and even hexane. Absorption spectral changes of the functional MPcs during addition of AgI and PdII soft-metal ions are evaluated by monomer-oligomer and even polymer formations technique and monitored for in situ monitoring technique in the UV-vis spectroscopy. The binding process results in considerable blue-shift in the absorption spectra of MPcs. According to continuous variation method, the ligand:metal ratio was found ca. 1:1 and 1.5:1 for total concentration of 1.0 × 10-5M and 7.5 × 10-5M, respectively. Their electrochemical and spectroelectrochemical studies show that the complexes exhibited stable monoanionic M{Pc[S-CH(CH2CH2CH3)(CH2CH2OH)]4}1-, dianionic M{Pc[S-CH(CH2CH2CH3)(CH2CH2OH)]4}2- and monocationic M{Pc[S-CH(CH2CH2CH3)(CH2CH2OH)]4}1+ species during reduction and oxidation processes.

Electrochemical hydrogen peroxide sensor based on cobalt phthalocyanine captured in polyaniline film on a glassy carbon electrode

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.