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A series of 11 low melting ionic liquids based on meso-substituted A₃B-porphyrins and A₂B₂-porphyrins containing one or two pyridyl substituents have been synthesized in high yields. Three of them are liquids at room temperature. All these porphyrinic salts were characterized by ¹H NMR, ¹⁹F NMR, MALDI-TOF mass spectrometry, elemental analysis and UV-visible spectroscopy. The thermal properties and conductivity values of these salt derivatives have been also measured. A specific conductivity value of up to 4 mS.cm^-1 could be obtained for a compound having the counter-anion B(C₆F₅)₄^-.

Ti(IV) phthalocyanines axially coordinated to 2,3- and 1,8-naphthalenediols have been prepared and characterized. The naphthalene axial ligands have been endowed with none, one or two sulfonate anchoring groups in order to study the performance of the dyes as DSC photosensitizers. All studied compounds showed the same efficiency. The unexpected results suggest displacement of the axial ligand with concomitant formation of a di-μ-oxotitanium-type anchoring moiety between the hydroxylated TiO₂surface and the Ti-phthalocyanine. This is probably the reason why the type of axial ligand does not play any role on the overall device efficiency. The titanium phthalocyanine absorbed in this way shows state selective electron injection were only those photons absorbed by the Soret band are capable to inject electrons into the TiO₂, while photons absorbed by the Q-band result in negligible photocurrent. This fact could explain the low efficiency of the Ti-phthalocyanines.

A phthalonitrile precursor 4-(3-hydroxypropylmercapto)phthalonitrile (3) was synthesized via a base-catalyzed nucleophilic aromatic nitro displacement of 4-nitrophthalonitrile with the 3-mercapto-1-propanol. A novel tetrasubstituted metal-free phthalocyanine (4) (M = 2H) and its metal complexes (5–8) (M = Zn, Ni, Cu and Co) bearing 3-hydroxypropylmercapto moieties were prepared by the cyclotetramerization reaction of (3) with the appropriate materials. The visible spectra of the zinc(II) phthalocyanine (5) was recorded with different concentrations and different ions as Ag⁺, Hg²⁺ and Pb²⁺ in DMF and also with different solvents as dimethylformamide and pyridine. Fluorescence spectrum of the compound (5) was also studied. Temperature and frequency dependence of AC conductivity for (4–8) was investigated in air and under vacuum and were found to be ~10^-8–10^-5 S.m^-1. Thermal properties of the phthalocyanines were examined by differential scanning calorimetry. All the novel compounds have been characterized by elemental analysis, UV-vis, FT-IR, NMR and MS spectral data and DSC techniques.