Protonation of meso-Tetraphenylporphyrin and Its beta-Functionalized Derivatives by Photogenerators of Acidity in Toluene and Polymer Film

The interaction of free-bases and Zn(II) complexes of meso-tetraphenylporphyrin, and its beta-functionalized derivatives with photogenerators of acidity (PGAs, hexachloroethane or tribromoethanol) has been studied in toluene and also embedded in polymer films. The free-bases undergo fast reversible protonation during the irradiation procedure. The photoprotonation of free-bases by PGAs is accompanied by the fluorescence decay of each porphyrin substrate. The relative rates of such photoprotonation of free-base porphyrins depend to a certain extent on the porphyrin structure. The similar protonation and the fluorescence decay of the meso-tetraphenylporphyrin derivatives in the presence of PGAs also take place in a polymer film. The related Zn(II) complexes undergo photolysis under the conditions used with the fluorescence decay as well. The protonation and sharp fluorescence decay of meso-tetraphenylporphyrin derivatives during their irradiation can find application in photosensmy technologies, information optical recording and antibacterial phototherapy.