Synthesis of non-peripherally and peripherally substituted zinc (II) phthalocyanines bearing pyrene groups via different routes and their photophysical properties

• Zinc (II) phthalocyanine and pyrene substituted derivatives have been synthesized.
• Two different routes are used for comparative synthesis.
• Substitutions effect on the properties of complexes has been investigated.
• Fluorescence lifetimes and fluorescence of these compounds are studied.
• The quenching of the fluorescence intensities was examined.

This work reports on photophysical properties of the non-peripherally and peripherally substituted zinc phthalocyanines (Pcs) prepared by two different synthetic routes. Tetra-substituted non-peripheral (5) and peripheral (6) zinc phthalocyanines containing 4-mercaptophenol groups were synthesized from novel phthalonitrile derivatives for the first time. Pyrene-containing phthalocyanine derivatives (7–8) were obtained by the reaction of compounds 5–6 with 1-bromoacetylpyrene. In the second route, compounds 7–8 were prepared by cyclotetramerization of pyrene-containing phthalonitrile derivatives (3a or 4a). The synthesized compounds were characterized by elemental analysis, FT-IR, UV–Vis, NMR spectroscopy and mass spectra. General trends were described for electronic absorption, fluorescence quantum yields, lifetimes, and fluorescence quenching by benzoquinone of these compounds. The effects of position of substituent on photophysical properties of the tetra-substituted zinc Pcs were also investigated.

The synthesis, characterization and photophysical properties of the non-peripherally and peripherally substituted zinc phthalocyanines (Pcs) bearing mercaptophenol groups and their pyrene containing analogs prepared by two different synthetic routes for the first time in this study. Photophysical and photochemical studies were carried out in order to determine the potential of the complexes as photosensitizers for use in photodynamic therapy.Figure optionsDownload as PowerPoint slide