Photophysical, photochemical and fluorescence quenching studies of new halogenated phthalocyanine metal complexes

Abstract

This study provides an accurate description of the preparation of some new quad-compensatory phthalocyanine complexes of Zn(II) and Cu(II) substituted by 4-(4-bromo-2-formylphenoxy). Several spectroscopic techniques have been employed to characterize phthalocyanine metal complexes including FT-IR, NMR, mass spectrometry, and UV-Visible spectrophotometry. Aggregation studies have been investigated in various DMSO concentrations ranging from 2×10–6 M to 10×10–6 M. In this research, the bathochromic shift of the Q band of [Zn(Pc)] depends on the solvent type in the following ascending order: (THF< DMF< CHCl3< DMSO and H2SO4), and for [Cu(Pc)] is (THF< DMSO< DMF< CHCl3 and H2SO4) respectively. Photophysical properties of the resulting complexes have been evaluated by measuring factors such as absorption and emission. Spectral results show that both complexes 2 and 3 have the potential to be used as sensitizers in photodynamic therapy (PDT) based on their singlet oxygen efficiencies (UD = 0.41, 0.39).