The Sn(IV)-tetra(4-sulfonatophenyl) porphyrin complexes with antioxidants: Synthesis, structure, properties

摘要

Complexes of Sn(IV)-tetra(4-sulfophenyl)porphyrin with antioxidants (methoxydol and ionol) and their precursors (para-cresol and 3-hydroxypyridine) were synthesized. All four complexes were obtained by boiling in aqueous solutions of the p-sulfo substituted Sn(IV) dihydroxytetraphenylporphyrin with the corresponding phenols. The structure of the obtained compounds was confirmed by NMR spectroscopy and mass spectrometry methods and quantum chemical calculations. Fluorescent properties of the diphenol complexes of Sn(IV) porphyrins and their photochemical stability in the presence of hydrogen peroxide in buffer media were investigated. It was shown that complexes with antioxidant ligands (ionol and methoxydol) have higher quantum yields and are more resistant to macrocycle destruction than complexes with other phenols and Sn(IV) dihydroxytetraphenylporphyrinate complexes. The main reasons for higher stability and weak quenching of fluorescence intensity are the presence of alkyl groups in the ortho-positions of the phenolic rings in the ionol and methoxydol molecules.