Ali Ihsan Okur

Novel crown ether-substituted phthalocyanines

Abstract A novel macrocycle has been synthesized from 4′-(α-bromoacetyl)benzo-15-crown-5, 4-nitrophthalonitril and diethyl malonate; its cyclotetramerization gives Cu(II), Co(II) and Pd(II) phthalocyanines (Pcs) with four benzo-15-crown-5 substituents on the periphery. The effects of alkali metal cations with these Pcs has been investigated through the changes in the visible spectra. The newly synthesized compounds have also been characterized by elemental analyses, IR, 1 H NMR.

Synthesis and Properties of Phthalocyanines Substituted with Four Crown Ethers

Abstract New phthalocyanines substituted with four benzo-15-crown-5 units through flexible -CH2-O- chains have been synthesized from 1- {[(benzo-15-crown-5)-4′-yl]oxymethyl}-3,4-dibromo (3) or -dicyano- -benzene (4) and hydroquinone or metal salts. The crown ether group in these phthalocyanines is shown to form intermolecular sandwich type complexes with alkali metal ions leading to the aggregation of molecules.

Novel two-fold-macrocycle-substituted phthalocyanines

New metallophthalocyanines (M = Cu or Ni) substituted in peripheral positions with four 14-membered tetraaza macrocycles each attached to a 15-membered crown ether have been prepared in a multi-step reaction sequence. The N-tosylated derivatives are extensively soluble in apolar solvents and form adducts with alkali-metal cations. Detosylation of the macrocyclic aza groups provides donor sites for binding transition-metal ions (e.g. NiII) which leads to pentanuclear water-soluble complexes.

New phthalocyanines containing bulky electron rich substituents

Metal-free and metallophthalocyanines with four 9-anthroyl groups bound through ethylthio ester bridges on the periphery have been prepared. The new compounds were characterized by elemental analyses, 1H NMR, IR, mass and UV-vis spectral data. The electronic spectra exhibit an intense π-π* transition of 9-anthroyl identity together with characteristic Q and B bands of the phthalocyanine core. Effect of metal ions on intensity of fluorescence spectra of phthalocyanine derivatives substituted with 9-anthroyl groups was investigated. The energy transfer to the phthalocyanine core and radiative decays of the 9-anthroyl emission and phthalocyanine core were examined.

Synthesis of 4′,5′-Bis(salicylideneimino)benzo[15-crown-5] and Its Complexes with Uranyl(VI), Copper(II), Nickel(II), and Cobalt(II)

Abstract 4′,5′-Bis(salicylideneimino)benzo{15-crown-5} (SALH2) has been synthesized from 4′,5′-diaminobenzo{15-crown-5} and salicylaldehyde. The crystalline sodium nitrate complex of the ligand (SALH2.NaNO3.H2O) has also been isolated. As an N2O2-donor ligand, SALH2 forms 1:1 metal complexes with various metals {SAL(M)xH2O where M = UO2(VI), Cu(II), or Ni(II)}. The octahedral Co(II) complex of SALH2 is capable of binding molecular oxygen. Also prepared were the complexes which simultaneously contain both sodium and transition metal ion. 1H-n.m.r., i.r., u.v.-visible, and conductance data are presented.

ELECTROCHEMICAL STUDIES OF TETRACROWN-ETHER SUBSTITUTED PHTHALOCYANINES IN SOLUTION

Abstract Cyclic voltammetry of soluble metal-free and copper phthalocyanines with crown ethers attached to the periphery through oxymethyl bridges show two one-electron reduction processes on sweeping to negative potentials. The addition of sodium or potassium ions to the solution results in a decrease in diffusion coefficients, which is a consequence of intermolecular complex formation in the presence of these two cations.

Synthesis and characterization of novel phthalocyanines substituted with four tetraaza macrocycles

A novel copper phthalocyanine substituted with four 14-membered tetraaza macrocycles and its pentanuclear nickel(II) complex were synthesized and characterized by elemental analysis, and IR and UV spectroscopy.

Tetranuclear supramolecular structures containing phthalocyanine cores

A metal-free phthalocyanine with four pyridyl donor groups, bound through ethylthio ester bridges on the periphery, have been prepared. The pyridine donors were quaternized with iodomethane to a water-soluble tetracationic phthalocyanine. The tetranuclear supramolecular phthalocyanine was prepared by the coordination of peripheral pyridine donors with VO(acac)2. The paramagnetic tetranuclear structure was studied in powder and solution forms by the electron paramagnetic resonance (EPR) technique. Electron paramagnetic resonance studies, together with the other spectral data confirmed the presence of identical pyridine-coordinated VO(acac)2 paramagnetic centers attached to the peripheral positions of the phthalocyanine core. The X-band EPR signals recorded from powder and solution forms of supramolecules have a characteristic line shape that proves the presence of axial symmetry around the paramagnetic vanadium ions. The anisotropic Lande splitting factors were calculated as g∥ < g⊥ < ge = 2.0023. Orbital energy levels for magnetic electrons were determined from theoretically fitted Spin Hamiltonian parameters.

Unsymmetrical phthalocyanines with cyclopalladated azo functions

In this study, a synthetic procedure for unsymmetrical metallophthalocyanines of the form M[Pc(AB3)], where A and B refer to two different types of peripheral functionality, has been developed and the new compounds have been converted to monomeric and dimeric palladium complexes. Asymmetrically substituted phthalocyanines were synthesized with the well-known statistical condensation method, by using two differently substituted precursors, namely 4-(2-ethoxyethoxy)-1-2-dicyanobenzene (1) and 4-{4-[Z/E]-phenylazo]-1-naphthyl}oxy-1,2-dicyanobenzene (2). Consequently, electron-donating 2-ethoxyethoxy groups and electron-withdrawing palladium complex are present in the same structure. Cyclopalladation was performed with [Pd(PhCN)2Cl2] to yield the bis-μ-chloro-bridged dimers and subsequently, the corresponding monomers were obtained by refluxing with three equivalents of potassium acetylacetonate. The resulting products were purified by column chromatography and characterized by several chemical and spectroscopic analysis methods. All compounds have very high solubility in organic solvents due to the presence of 2-ethoxyethoxy moiety.

Template reactions of 1,4-bis(α-carboxybenzylidenehydrazino)phthalazine with cobalt(II), nickel(II), and chromium(III)

1,4-Bis(α-carboxybenzylidenehydrazino)phthalazine (1) has been prepared from 1,4-dihydrazinophthalazine and the methyl ester of phenylglyoxylic acid. The reaction of (1) with cobalt(II) and nickel(II) gives isostructural macrocyclic complexes [(2a) and (2b)] as a result of the template effect of these metal ions. In the case of the chromium(III) ion, a similar template reaction has not been observed, which is proposed to be due to the six-co-ordinate environment adopted by the CrIII ion. Mass, i.r., n.m.r., and u.v.–visible data of the novel compounds are presented.