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Abstract: With the aim of preparing a novel Zn phthalocyanine bearing four phenylboronic azaester substituents at peripheral positions, 4-[2-(bis(2-hydroxyethyl)amino)ethoxy]phthalonitrile (2) was synthesized by the aromatic nucleophilic substitution reaction of 4-nitrophthalonitrile with triethanolamine. 2,9(10),16(17),23(24)-Tetrakis-[2-(bis(hydroxyethyl)amino)ethoxy]-phthalocyaninatozinc (II) (4) was prepared from the cyclotetramerization of dinitrile 2 in the presence of anhydrous zinc(II) acetate by microwave irradiation. Alternatively, treatment of 2 with phenylboronic acid yielded the phenylboronic azaester (3), namely 4-(2-(2-phenyl-1,3,6,2-dioxazaborocan-6-yl)ethoxy)phthalonitrile. Treatment of phthalocyanine 4 with phenylboronic acid in a mixture of DMSO/toluene (20/1, v/v) afforded the desired phthalocyanine 5. The novel compounds were characterized by elemental analyses, IR, UV–Vis, 1H, 13C and 11B NMR spectra. The 11B NMR data indicated that the boron atom of phthalonitrile 3 is in the tetracoordinated state with the formation of a coordinative Nlosed form), while in the case of phthalocyanine 5, the open conformer possessing a tricoordinated B atom is favoured. [Copyright &y& Elsevier]

A novel Zn phthalocyanine bearing 4 salicylideniminophenyloxy substituents on peripheral positions was synthesized from the reaction of 4-aminophenoxy substituted phthalocyanine and salicylaldehyde. The condensation reaction of salicylidene Schiff base groups and benzeneboronic acid produced a new phthalocyanine carrying benzeneboronic acid ester derivatives as substituents. Ethoxy groups were bound to boronic acid as a second ligand. The presence of B-N bond interactions enhanced the stability of this boronated phthalocyanine derivative, which exhibited sufficient air stability during the purification and characterization processes. The novel compounds were characterized by using elemental analysis, IR, ¹H-NMR, 11 B-NMR, 13C-NMR, UV-Vis and MALDI-TOF MS spectral data. [ABSTRACT FROM AUTHOR]

Porphyrins, phthalocyanines, tetrabenzo porphyrins and porphyrazines which are tetrapyrrole derivatives. Because of both theoretical studies and applications in advanced materials science, tetrapyrrole derivatives receive extensive attention. Porphyrins are important not only from biological aspect but also for coordination chemistry as catalysis and material science. Phthalocyanines which are used in electro-photography, optic data collection, gas sensor, liquid crystal, laser technology and the photodynamic therapy of tumors as well as their classical fields as pigments and dyes, are completely synthetic materials. Porphyrazines that have functionalized groups at pheripheral positions have the potential to exhibit novel optical, magnetic and electronic properties. They also maintain some additional features superior to the values met in related materials. Additions of the transition metal ion in the inner core of a porphyrazine offer new ways to induce, modify and control molecular properties. The starting point for a novel porphyrazine structure with eight (1- naphthyl) groups bound to the periphery is 1,2-bi ( naphthyl )dinitrile which was obtained by oxidative coupling of 1-naphthylacetonitrile in the presence of I2. The solid product was obtained in a yield of 21%. It was a mixture of maleo-and fumaro-nitriles and the latter was present in higher ratio as expected from the presence of bulky naphthyl substituents. The mixture of maleo-and fumaro-nitrile reluctance to turn into porphyrazine under the usual conditions (i.e. Mg(OR)2 in refluxing propanol or butanol) points out the lower ratio of the maleonitrile component. This problem was solved by activation of the fumaronitrile derivative to the corresponding pyrroline derivative 3,4-(1-naphthyl)pyrroline-2,5- diimine which cyclizes quite easily to porphyrazine at reflux temperature of propanol or butanol. Conversion of 3,4-(1-naphthyl)pyrroline-2,5-diimine into porphyrazine was achieved by the template effect of magnesium butanolate. Cyclotetramerization gave green-colored octakis(1-naphthyl) porphyrazinato magnesium in yield (70%). It is soluble in chloroform, dichloromethane and acetone, but insoluble in apolar hydrocarbon solvents such as n-hexane. Intensive research interest on peripherally functionalized porphyra-zines during the last decade has shown that these tetrapyrrol derivatives should be considered in many respects as an alternative to phthalocyanines. The porphyrazine macrocycles afford a skilful platform to build up detailed molecular superstructures and this property coupled with a full and well-improved synthetic chemistry has surpassed to the synthesis of different catalytically essential metallo porphyrazines and original model compounds of various functions.… [ABSTRACT FROM AUTHOR]

Abstract: Metal-free 3 and metallophthalocyanines 4, 5 (Nith four, peripheral 4-pyridylmethyloxy groups were synthesized by cyclotetramerization of 4-(4-pyridylmethyloxy)-phthalonitrile (2). The zinc derivative 5 was converted into the water-soluble quaternized product 6 by its reaction with methyl iodide. The new compounds were characterized by elemental analysis, IR, NMR and their mass and electronic spectra. [Copyright &y& Elsevier]

A new phthalonitrile derivative with two different substituents on 4- and 5-positions has been synthesized and its cyclotetramerization in the presence of anhydrous metal salts without any solvent resulted with phthalocyanines (4–6) containing a hexylthio group and malonylester on each benzo unit. When phthalocyanine formation was carried out in high-boiling alcohols in the presence of a base transesterification of malonyl esters gave products with enhanced solubility in apolar solvents. These new compounds have been characterized by 1H NMR, FT-IR, UV–vis and mass spectroscopies. [Copyright &y& Elsevier]

Abstract: Metal-free and Co(II)-phthalocyanines carrying eight dodecaborate substituents (96 boron atoms) on the peripheral positions were synthesized in a multistep reaction sequence. The first step of the preparation of metal-free and Co(II) target phthalocyanines was cyclotetramerization of 4-(3,5-dimethoxyphenoxy)phthalonitrile in pentanol in the presence of lithium pentanolate and Co(II) salt, respectively. After cleavage of methyl groups the reaction of (Bu4N)[B12H11O(CH2CH2)2O] with hydroxyphenoxy substituted phthalocyanines gives the novel phthalocyanines 7, 8 with eight dodecaborate units. The new phthalocyanine compounds were characterized by NMR, FT-IR and UV–VIS spectral data. The electrochemical investigations of cobalt(II) phthalocyanine together with Zn(II) derivative having identical substituents were studied. [Copyright &y& Elsevier]

Abstract: Zinc(II)phthalocyanine with four naphthoxy pendant groups on the periphery was prepared by cyclotetramerization of 4-(2-naphthoxy)phthalonitrile. Thin films of this material have been prepared from solutions of different concentrations (5–100mg ZnPc in 1mL THF) by spin coating technique. Optical transmittance of thin films was measured using a spectrophotometer in the wavelength range of 260–1100nm. Results show that transmittance is decreased with the increasing concentration in the ranges corresponding to B and Q absorptions, but the films can still be proposed as optical windows between these regions (~400–600nm) due to very low absorbances. The surface morphology of the thin films was investigated by atomic force microscopy, AFM, and showed that all of the films have nano volcanic holes, except the film prepared from the most concentrated solution (100mg ZnPc in 1mL THF). [Copyright &y& Elsevier]

Abstract: Porphyrazines (M=H, Mg, Zn and Co) with a 2,3-dicyano-5-phenyl-5,6-dihydro-1,4-dithiin group fused to each pyrrole unit were synthesized and characterized starting with the corresponding unsaturated dicarbonitrile derivative. The voltammetric and spectroelectrochemical characterizations of the metallo-porphyrazines (M=2H+, Mg2+, Zn2+ and Co2+) substituted with 2,3-dicyano-5-phenyl-5,6-dihydro-1,4-dithiin groups on peripheral positions are described. Cyclic voltammetry and differential pulse voltammetry studies showed that while metal-free, magnesium, and zinc porphyrazines represented well-defined one-electron ligand-based reductions and ligand-based one-electron oxidation couples, cobalt porphyrazine gave both metal-based and ligand-based reduction and oxidation couples. Assignments of the redox couples were confirmed by spectroelectrochemical measurements. [Copyright &y& Elsevier]

Abstract: Novel phthalocyanines with biphenyl substituents and ester groups that are readily soluble in organic solvents were synthesized from a phthalonitrile derivative obtained by displacement of the –CH proton in 1-chloro-3,4-dicyano-6-(1,1-dicarbethoxymethyl)benzene with 4-(chloromethyl)biphenyl, followed by cyclotetramerization in the presence of metal salts {CuCl2, Pb(CH3COO)2·3H2O, CoCl2 and Zn(CH3COO)2}. Transesterification of malonyl esters occurred during the cyclotetramerization of dinitrile with CuCl2, Pb(CH3COO)2·3H2O in 1-pentanol in the presence of DBU. The structures of the newly synthesized molecules were verified using elemental analysis, 1H NMR, FT-IR, MicroTOF mass and UV–vis spectral data. [Copyright &y& Elsevier]

Abstract: A new phthalonitrile derivative bearing dimethylaminoethylsulfanyl- and diethoxymalonyl-substituents at peripheral positions has been synthesized. Cyclotetramerization of this dinitrile in hexanol gave the desired cobalt(II) and zinc(II) phthalocyanines (4 and 5) with dimethylaminoethylsulfanyl and dihexoxymalonyl groups on periphery. Four dimethylaminoethyl groups of the former were quaternized to yield a water-soluble cobalt(II) phthalocyanine. Electrochemical redox properties of these phthalocyanines were investigated by cyclic voltammetry and applied chronocoulometry techniques. [Copyright &y& Elsevier]

Abstract: Zn(II), Co(II), Ni(II) and metal-free phthalocyanines (2–5) bearing a hydroxyethylthio substituent on each benzo group were prepared from 4-(hydroxyethylthio)phthalonitrile (1) and the corresponding divalent metal salt. The reactivity of the hydroxyethyl groups was demonstrated by esterification of phthalocyanine derivatives (2–5) with acetic anhydride at reflux temperature and acetylated phthalocyanine compounds (6–9) were obtained. The new compounds have been characterized by elemental analyses, IR, UV–vis, mass and 1H NMR spectroscopy. [Copyright &y& Elsevier]

Porphyrazines (M=H, Mg, Zn or Cu) with 2,3-trimethyleneoxy-2,3-dihydro-1,4-dithiin or 2-ethoxy-2,3-dihydro-1,4-dithiin groups fused to each pyrrol unit have been synthesised starting with the corresponding unsaturated dicarbonitrile derivative. The elemental analysis and IR, 1H NMR, UV–Vis and mass spectral data have been used to characterise the new compounds. Electrochemical investigations have shown that metal insertion into the porphyrazine core and substituents having high electron donating ability shift the ring centred reduction processes towards negative potentials. [Copyright &y& Elsevier]

A novel multicomponent system consisting of benzene-1,4-diyldimethanimine bridged dimeric zinc-phthalocyanine groups was synthesized. Firstly, a novel unsymmetrically nitro and 2,4-di- tert -butylphenoxy groups substituted zinc (II) phthalocyanine was synthesized and then nitro group was reduced to amino functional group. All newly synthesized compounds were characterized by UV–Vis, FTIR, 1 H-NMR, MALDI-TOF MS and elemental analysis spectral data. The potential of these compounds as gate dielectric were investigated by fabricating bottom gate top contact OFET using poly 3-hexylthiophene-2,5-diyl as active layer. Field effect mobility values of 3.2 × 10 −4 cm 2 /V s was obtained when using ITO-coated glass as gate electrode. It was found that the density of leakage current was about 2 nA/cm 2 at 5 V. The capacitance density of 11.8 nF/cm 2 was achieved at a frequency of 5 Hz with slightly smaller values at higher frequency. [ABSTRACT FROM AUTHOR]

Abstract: A novel Zn phthalocyanine substituted with four dimethylaminocinnamaldiminophenyloxy substituents at peripheral positions was obtained by the condensation of various 4′-aminophenoxy substituted phthalocyanines and 4-(dimethylamino)cinnamaldehyde. Quaternization of the dimethylamino functionality produced cationic Zn phthalocyanines which were soluble in both water and other polar solvents such as methanol and DMSO. The novel compounds were characterized using elemental analysis, IR, 1H NMR, UV–Vis and MALDI-TOF MS spectral data. Electrochemical, in situ spectroelectrochemical, and in situ electrocolorimetric measurements revealed that the complexes undergo electron transfer reactions via the nitro and amine groups in addition to common Pc ring-based processes. [ABSTRACT FROM AUTHOR]

Abstract: 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 copper(II) acetate, zinc(II) acetate and cobalt(II) acetate led to the metal porphyrazinates (M=Cu, Zn, Co). These new compounds have been characterized by elemental analysis, together with FT-IR, 1H NMR, UV–Vis spectral data. By using EPR technique, room temperature paramagnetic properties of Cu(II) doped porphyrazine sample as powder and solution forms were measured. The first-derivative EPR signals taken from as powder and solution forms shows that the sample is axially symmetric. The trend g ∥ > g ⊥ >2 indicates that the unpaired electron is located mainly in the orbital (2B1 as ground state). [Copyright &y& Elsevier]

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 derivative was obtained by its treatment with trifluoroacetic acid and further reaction of this product with copper(II) acetate, zinc(II) acetate and cobalt(II) acetate led to the metal porphyrazinates (M=Cu, Zn, Co). These new compounds have been characterized by elemental analysis, together with FT- IR, 1H NMR, UV–Vis and EPR spectral data. [Copyright &y& Elsevier]

Phthalocyanines with four naphthoxy pendant groups on the periphery were prepared by cyclotetramerization of 4-(1-naphthoxy)phthalonitrile and 4-(2-naphthoxy)phthalonitrile. The new compounds were characterized by elemental analyses, 1H NMR, IR and UV–Vis spectral data. The electronic spectra exhibit an intense π→π* transition of naphthyl identity together with characteristic Q and B bands of the phthalocyanine core. [Copyright &y& Elsevier]