Phthalocyanines with bromobenzenesulfanyl substituents at non-peripheral position: Preparation, photophysical and photochemical properties

Electron-donating bromobenzenesulfanyl-group-substituted phthalonitrile derivative (1) and its novel non-peripherally tetra-substituted metal-free, indium and zinc phthalocyanine complexes (2-4) have been prepared for the first time. The chemical structures of this new phthalonitrile and its phthalocyanine derivatives were characterized by UV-vis, FT-IR, NMR, and MALDI-TOF mass spectrometry. The introduction of this electron-donating sulfanyl type of non-peripheral substituent accounts for a remarkable red shift of the phthalocyanine Q band to approximately 730 nm. Photophysical and photochemical properties of the novel functional complexes were also examined as photosensitizers for PDT applications.