Synthesis and characterization of polyimides with ether linkages

Thermoplastic and thermoset polyimides derived from 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) and 4,4′-bis(4-aminophenoxy)-2,2′-dimethylbiphenyl (BAPD) were prepared and characterized. Their physical and thermal properties as well as the polyelectrolyte effect exhibited by BTDA–BAPP polyamic acids in NMP solution were discussed. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2559–2567, 1999     

Synthesis and characterization of new polyfluorinated dendrimeric phthalocyanines

The synthesis of new polyfluorinated dendrimeric metallophthalocyanines (M = Zn, Ni, Co) bearing 3,5-bis(2′,3′,4′,5′,6′-pentafluorobenzyloxy)benzyloxy moieties (2–4) was achieved by cyclotetramerization of phthalonitrile derivative 1 in the presence of zinc, nickel or cobalt salts in DMF. All the target phthalocyanines were separated by column chromatography and their spectroscopic, fluorescence and energy transfer properties, and aggregation behavior were investigated in different solvents and at different concentrations in chloroform. The compounds were characterized by Fourier transform-infrared, fluorine, proton and carbon nuclear magnetic resonance, mass, ultraviolet–visible and fluorescence spectral data. The phthalocyanines (2–4) were extremely soluble in various organic solvents, such as tetrahydrofuran, acetone and dichloromethane.     

Synthesis and characterization of liquid crystalline unsymmetrically substituted phthalocyanines

The synthesis of unsymmetrically substituted phthalocyanines bearing two p-tolyl-sulfonyl (tosyl)amido and six alkylthio moieties was achieved by cyclotetramerisation of two different phthalonitrile derivatives, namely 1,2-di(alkylthio)-4,5-dicyanobenzene and 4,5-dicyano-N,N′-ditosyl-o-phenylenediamine in the presence of an anhydrous metal salt and strong base. The new compounds were characterized by elemental analyses, UV/Vis, IR, NMR and mass spectra. The mesogenic properties of these new materials were studied by differential scanning calorimetry (DSC) and polarizing optical microscopy. The mesogenic properties of these compounds were compared to that of their symmetric analogous, octaalkythia substituted phthalocyanine derivatives.     

Synthesis and characterization of novel phthalocyanines bearing quaternizable coumarin

The synthesis of novel metal-free and zinc phthalocyanines with four 3-[(2-diethylamino)ethyl]-7-oxo-4-methylcoumarin dye groups on the periphery were prepared by cyclotetramerization of a novel 3-[(2-diethylamino)ethyl]-7-[(3,4-dicyanophenoxy)]-4-methylcoumarin. The novel chromogenic compounds were characterized by elemental analysis, ¹H NMR, ¹³C NMR, MALDI-TOF, IR and UV–Vis spectral data. The electronic spectra exhibit bands of coumarin identity along with characteristic Q and B bands of the phthalocyanine (Pc) core. The IR spectra of all the Pcs showed three characteristic intense bands, at 1704 cm⁻¹ for the lactone carbonyl and two bands at 1489–1604 cm⁻¹ for the conjugated olefinic system.     

Synthesis,characterization and electrochemical properties of new phthalocyanines

The chemical synthesis and characterization with spectroscopic and electrochemical properties of [bis(4-fluorophenyl)-methoxy]-substituted metallo-phthalocyanines were reported for the first time. The new phthalocyanines have been characterized by elemental analysis, UV-Vis, FT-IR, and mass spectroscopies. The aggregation behavior of the phthalocyanine compounds was investigated in different solvents and concentrations. It is found that the fluoro substituents of peripherally Co and Cu complexes are examined and induce a shift to the redox processes toward the negative potentials and formed more reversible processes. Metal-based reduction and oxidation reactions were obtained for the Co(II) complex, whereas Cu(II) complexes exhibited Pc-ring-based electron-transfer reactions. The voltammetric measurements supported the proposed structure of the complexes.     

Synthesis and characterization of new polyimides containing ethynylene linkages

We have synthesized a series of new diamines containing bis(ethynylaniline) linkages by bromine substitution reaction of ethynylaniline with 4,4′-bis(4-bromophthalimido)diphenylether (PODA) or 1,4-bis(4-bromophthalimido)benzene (PPDA). The intermediates were separated at each step, purified and characterized by the spectroscopic techniques. The model compound having imide and triple bond moiety was synthesized in order to elucidate the nature of the products formed from the ethynyl curing by FT-IR spectroscopy. The polymerization reaction of ethynylaniline diamines with various dianhydrides gave fully imidized and soluble aromatic polyimides. The thermally cured polyimide samples displayed good solvent resistance. The thermal crosslinking of triple bond moieties in the main chain was carried out by heating in the temperature range from 150 to 400 °C. The glass transition temperature of polyimide completely disappeared after heat treatment at 400 °C for 5 min. The polyimides derived from diamines containing bis(ethynylaniline) groups were thermally stable after heat treatment.     

Synthesis and characterization of liquid crystalline tetra- and octa-substituted novel phthalocyanines

Methylene-bridged tetra- and octa-(13,17-dioxa nonacosane-15 sulfanyl)-substituted metal free- and Ni(II) phthalocyanines were synthesized from the corresponding phthalonitrile (3, 4) derivatives in the presence of the anhydrous metal salt (NiCl₂) or a strong organic base. The new compounds were characterized by elemental analyses, UV/Vis, IR, NMR and mass spectra. The mesogenic properties of these materials were studied by differential scanning calorimetry (DSC), optical microscopy and X-ray diffraction investigations. X-ray diffraction patterns of the mesophase confirm that tetra- and octa-substituted compounds (3a–b, 4a–b) form hexagonal columnar mesophases (Col_h). We indicated that addition of the methylene-bridged phthalocyanine (Pc) core can either decrease the liquid crystal phase transition temperatures or extend the liquid crystal temperature range to include room temperature. Also, the Pc compounds (3a, 3b, 4a and 4b) are liquid crystals at room temperature. These properties of the Pc complexes provide some advantages such as easily obtaining an ordered film for sensor applications. Computational modelling work was combined with X-ray diffraction investigation to validate the diameter of the phthalocyanine molecule (3b).     

Synthesis, characterization and nonlinear optical properties of nonaggregating hexadeca-substituted phthalocyanines

The microwave-assisted synthesis, characterization and photophysical properties of hexadeca-substituted phthalocyanine (Pc) complexes with bulky phenoxy substituents are reported. NMR and UV-Vis analyses confirm the ability of bulky groups to induce steric isolation of Pc cores even in the solid state. The Z-scan measurement indicates that the Zn-containing derivative has promising nonlinear optical properties (NLOs).     

Synthesis and characterization of functionalized silicon phthalocyanines for fabrication of self-assembled monolayers

Novel octasubstituted phthalocyanine derivatives XYSiPc(OR)₈ (X=alkyl, Y=alkoxy, R=alkane or alkene) were synthesized by reaction of alkoxy-substituted diiminoisoindolines with XSiCl₃ followed by quenching with an alcohol YOH. Three synthetic routes for adding anchoring groups to the phthalocyanines were explored: variation of the axial groups X and Y, or incorporation of vinyl groups around the periphery of the phthalocyanine ring. The latter approach yielded silicon and copper phthalocyanines with eight terminal vinyl groups, which reacted cleanly with thioacetic acid/AIBN to give products with eight protected terminal thiols.     

Synthesis of nitroxide-functionalized phthalocyanines

A nitroxide-functionalized phthalonitrile and a diimino-isoindoline were prepared via Pd(0)-catalyzed cyanation from the corresponding dibromide and subsequent addition of ammonia, without interference from the radical moieties. The structures of these radicals were confirmed by single-crystal X-ray structure determinations. Metal-templated macrocyclization of these species under standard Linstead conditions or in 2-(dimethylamino)ethanol at reflux gave the corresponding metallated and free-base phthalocyanines, which were characterized using UV-vis, FTIR and EPR spectroscopy as well as mass spectrometry.     

Synthesis of tetrathiafulvalene-annulated phthalocyanines

The synthesis of three new TTF-annulated phthalocyanine (Pc) derivatives 5a-c are described. All of them have been characterized by elemental analysis, IR and UV-vis spectroscopy. In all cases, the incorporation of long and flexible aliphatic side-chains into the rigid TTF-annulated Pc core did not promote the formation of a discotic mesophase.     

Synthesis of sulfonamide-substituted phthalocyanines

The synthesis and characterization of new phthalocyanines bearing eight N-alkyl or N-aryl sulfonamide groups is described. The synthetic route involves the chorosulfonation of 4,5-diphenoxyphthalonitrile with chlorosulfonic acid and reaction of the resulting 4,5-bis(p-chlorosulfonylphenoxy)phthalonitrile with amines. The sulfonamide-substituted phthalonitriles are then cyclotetramerized to yield the title compounds in good yields (50–83%).     

Synthesis and characterization of novel flavonoid-substituted phthalocyanines using (±)naringenin

In this study, novel unsymmetrical mono- and di-substituted metal free and metallo phthalocyanines containing peripheral naringeninoxy moieties have been prepared. The naringenin-substituted phthalonitrile was synthesized from 4-nitrophthalonitrile and (±)naringenin in dimethylsulfoxide. Preparation of unsymmetrical mono- and di-substituted phthalocyanines, 2-naringenin-7-O-phthalocyaninatozinc, 2,9-bis-naringenin-7-O-phthalocyaninatozinc, 2,9-bis-naringenin-7-O-phthalocyaninatocobalt and 2,9-bis-naringenin-7-O-phthalocyanine was performed at 120-140 °C using the corresponding phthalonitrile in the presence of N,N-dimethylethanolamine (DMAE), ZnCl₂, CoCl₂ and LiCl, respectively. Synthesized new phthalocyanine compounds have been characterized by elemental analysis and ¹H NMR, ¹³C NMR, FT-IR, MS and UV-vis spectroscopy. These are the first known examples of flavonoid-substituted phthalocyanines.     

Synthesis,characterization, antioxidant and antibacterial properties of non-peripherally and peripherally tetra-substituted phthalocyanines

abstract

This study focuses on the synthesis, spectral, antioxidant and antibacterial properties of the metal-free, zinc and cobalt phthalocyanines (3–8) bearing 4-methoxy-phenoxy substituents on the nonperipheral [(1(4), 8(11), 15(18), 22(25)] or peripheral [2(3), 9(10), 16(17), 23(24)] positions. The new synthesized complexes 7 and 8 have been characterized by elemental analysis, FT-IR, MALDI-MS, and UV-vis spectral data. The antioxidant activities of all tested compounds were investigated by applying three different antioxidant methods such as radical scavenging ability of 1,1-diphenyl-2-picrylhydrazyl, chelating ability to ferrous ions and reducing power activity methods. In addition, the antibacterial activities of the compounds were screened by disc diffusion method against one gram-negative and four gram-positive bacteria. The tested phthalocyanine compounds showed very good antioxidant activity and promising antibacterial properties.     

Synthesis and characterization of new polymeric phthalocyanines substituted with diaza-18-crown-6 macrocycles through ethyleneoxy bridges

A tetranitrile monomer was synthesized by nucleophilic aromatic substitution of N,N′-bis(2-hydroxyethyl)-4,13-diaza-18-crown-6 onto 4-nitrophthalonitrile. A series of polymeric metal-free and metallophthalocyanine (M = 2H, Zn, Cu, Co and Ni) polymers was prepared by polymeric tetramerization reaction of the tetranitrile monomer with proper materials. The electrical conductivities of the polymeric phthalocyanines measured as gold sandwiches were found to be ∼10⁻⁹–10⁻⁴ S cm⁻¹ in a vacuum and in argon. The extraction ability of the metal-free polymeric phthalocyanine was evaluated in tetrahydrofuran using several alkali metal picrates such as Li⁺, Na⁺, K⁺ and Cs⁺. The extraction affinity of the metal-free polymeric phthalocyanine for K⁺ was found to be highest in the heterogeneous solid–liquid phase extraction experiments. The disaggregation property of the metal-free polymeric phthalocyanine was investigated with sodium, potassium and ammonium ions and methanol. All the novel compounds were characterized by using elemental analysis, UV–Vis, FT-IR, NMR and MS spectral data and DTA/TG.     

Synthesis and characterization of novel metal-free phthalocyanines containing four cylindrical or spherical macrotricyclic moieties

The novel metal-free phthalocyanines 8 and 9 bearing four peripheral tetraaza-dithiahexaoxa cylindrical or spherical macrotricycles have been synthesized by tricyclo-tetramerization of isoindolinediimine derivatives of supercryptands 6 and 7 and were characterized by elemental analysis, ¹H and ¹³C NMR, IR, MS and UV-vis spectral data.     

Synthesis,characterization and electrochemical properties of amphiphilic axially-disubstituted silicon(IV) phthalocyanines

The new 2-[2-(6-tert-butyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol 1 and 2-[2-(6-pentyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol 2 have been synthesized. Axially disubstituted silicon phthalocyanines 3 and 4 have been synthesized by introducing 2-[2-(6-tert-butyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol and 2-[2-(6-pentyl-2H-1,3-benzoxazin-3(4H)-yl)ethoxy]ethanol at the axial positions of silicon(IV) phthalocyanine, respectively. The electrochemical properties of silicon phthalocyanines 3 and 4 were also investigated by cyclic voltammetry (CV) and square wave voltammetry. Voltammetric studies show that while 3 showed two reversible reduction and one irreversible oxidation couples, 4 showed two quasi-reversible reduction and one irreversible oxidation couples.     

Synthesis,characterization and fluorescence behavior of new fluorescent probe phthalocyanines bearing coumarin substituents

In this study, we report a new ligand, 6-hexyloxy-3-[p-(3′,4′-dicyanophenoxy)phenyl]coumarin, and its fluorescent tetrasubstituted phthalocyanines {M[Pc(OBzCou)₄], M = 2H, Zn(II), Co(II); Bz: Benzene}. The effect of the coumarin derivative on the intensity of the fluorescence spectra of the metal-free (H₂Pc) and zinc phthalocyanine (ZnPc) derivatives was investigated. The change of the emission properties of both the coumarin moieties and the phthalocyanine core in the presence of the metal ion and the ring-opening reaction of the coumarin were studied by means of steady-state fluorescence spectroscopy. The radiative decay of the Pcs and the treated coumarin substituents bound to the Pcs was examined. The novel chromogenic compounds were characterized by elemental analysis, ¹H NMR, ¹³C NMR, Maldi-TOF, IR and UV–Vis spectral data. The photophysical properties of the Pcs are extensively affected by their state of aggregation: in particular, dimerization and aggregation result in a remarkable modification of the absorption and emission bands and may induce significant quenching of the usually strong Pc fluorescence. The electronic spectra exhibit a band of coumarin identity together with characteristic Q and B bands of the phthalocyanine core.     

Synthesis,characterization, conduction,and dielectric properties of tetra tert-butylsulfanyl substituted phthalocyanines

The tert-butylsulfanylphthalonitrile has been prepared with optimized synthetic procedure. Metal free (H₂Pc) and metallo phthalocyanines (Pcs) (ZnPc, CoPc, CuPc, PbPc) have been synthesized by cyclotetramerization of tert-butylsulfanylphthalonitrile in the presence of DBU and metal salts. Thus, tert-butylsulfanyl groups enhance the solubility, shift the Q band absorption to the red visible region, and inhibit efficient cofacial interaction of the Pcs (2–6) as evaluated by UV–vis spectra. The electrical conduction and dielectric properties of the synthesized Pc thin films sandwiched between indium tin oxide and aluminum electrodes (ITO–Pc–Al) were investigated from 300 to 500 K. At low bias voltage the conduction is ohmic while at high bias voltage the conduction becomes space charge limited with an exponential distribution of traps. The measured ac conductivity data are discussed in terms of classical models based on pair approximation. It was found that the ac conductivity obeys the power law given by σ_ac = σ₀ω^s, in which the frequency exponent s decreases with temperature. The real and imaginary parts of the impedance are found to be dependent on both frequency and temperature.