Synthesis and properties of 5,10,15,20-tetrakis[4-(3,5-dioctyloxybenzamido)phenyl]porphyrin and its metal complexes

A novel 5,10,15,20-tetrakis[4-(3,5-dioctyloxybenzamido)phenyl]porphyrin and its transition metal complexes are reported in this paper. Their molecular structures were characterized by elemental analysis as well as IR, H-1-NMR and UV-Vis spectroscopy. Their spectroscopic properties were studied by Raman and fluorescence spectroscopy, and X-ray photoelectron spectroscopy (XPS). The fluorescence quantum yields were measured at room temperature. The fluorescence intensity of the porphyrin ligand was stronger than the intensity of the complexes. There were large differences in the Raman spectrum of the porphyrin ligand and those of the metal complexes due to changes in the symmetry of porphyrin plane. In the XPS spectra, the replacement of the free-base protons by a metal ion to form the metalloporphyrin not only increases the symmetry of the molecule, but also introduces an electron withdrawing group into the center of the porphyrin ligand, which increases the N-1s binding energy.