SYNTHESIS AND CHARACTERIZATION OF HYBRID PORPHYRIN DIMERS AND HALOGENATED PORPHYRIN DIMERS

Zinc hybrid porphyrin dimer(ZnTTP-C-2-H2PFPP, ZnTTP-C-2-H2TTP, ZnPFPP-C-2-H2PFPP, and ZnPFPP-C-2-H2TTP) and manganese (III) halogenated porphyrin dimers (MnPFPP-C-2-MnPFPP, MnPFPP-C-2-MnDCPP, and MnDCPP-C-2-MnDCPP) covalently bridged by an ethylene moiety (Scheme 1) were synthesized and characterized by UV-vis spectra, fluorescence spectra, and cyclic voltammograms. These porphyrin dimers could be embedded into the lipid bilayers of a liposomal membrane. The redox potential of the manganese complex for the halogenated porphyrin dimers increased with increasing of halogen portions on the porphyrin rings. An efficient energy transfer of the excited singlet state in the covalently-linked zinc hybrid dimers from zinc porphyrin to a free base porphyrin was observed, depending on the porphyrin structure. Furthermore, the manganese halogenated porphyrin dimers acted as catalysts of transmembrane electron transfer; such activity depends on the steric effect of halogen portions on the porphyrin ring.