Effects of the electron-withdrawing power of substituents on the electronic structure and reactivity in oxoiron(IV) porphyrin .pi.-cation radical complexes

Abstract

The effects of the electron-withdrawing power of the substituents bound to a porphyrin ring on the electronic structures and the reactivities of oxoiron(IV) porphyrin π-cation radical complexes were studied by using 2,7,12,17-tetramethyl-3,8,13,18-tetraarylporphyrins (aryl=(1) mesityl, (2) 2-chloro-6-methylphenyl, 2,6-dichlorophenyl, or 2,4,6-trichlorophenyl). The electronic structures of oxoiron(IV) porphyrin π-cation radicals were investigated by low-temperature UV-visible absorption spectroscopy and proton NMR measurements.