Synthesis, Characterization, Photophysical and Photochemical Properties of Novel Phthalocyanines

Abstract

The benzothiazole substituted phthalonitrile (3) and nonperipherally tetra benzothiazole substituted metal-free (4), zinc (II) (5) and lead(II) phthalocyanine (6) complexes were prepared. The compounds (3-6) were characterized by IR, NMR, UV-Vis and mass spectroscopy data. After synthesis, photochemical and photophysical parameters of the compounds (4-6) were analyzed to determine photosensitizer performance of them for PDT applications. Firstly, the most suitable solvent for compounds (4-6) was found by aggregation studies. Then, fluorescence properties were measured in DMF at 1x10 À 6 M. Singlet oxygen properties were measured in DMF by using 1,3diphenylisobenzofuran (DPBF) as a singlet oxygen quencher. Photodegradation properties were measured under light irradiation in DMF at 1x10 À 5 M. The zinc(II) phthalocyanine (5) had the highest singlet oxygen production capacity (Φ~= 0.62), fluorescence (Φ F = 0.25) and photodegradation quantum yield (Φ d = 3.28x10-4). The results showed that zinc(II) phthalocyanine (5) has potential for photodynamic therapy applications.