Synthesis and Dissociation Kinetics of Zinc, Copper, Cobalt, and Manganese Complexes with 2,3,7,8,12,18-Hexamethyl-5-phenyl-13,17-diethylporphin and Its Nitro-Substituted Analogs in Proton-Donor Media

Nitro-substituted 2,3,7,7,8,12,18-hexamethyl-5-phenyl-13,17-diethylporphins with nitro groups in positions 10 and 20 of the porphyrin core and in the para-position of the benzene ring have been synthesized. The structure of the obtained compounds has been confirmed by H1 NMR, UV, and IR spectroscopy as well as mass spectrometry. The kinetics of dissociation of zinc, copper, cobalt, and manganese complexes of the obtained porphyrins in proton-donor media has been studied. The stability of the porphyrin metal complexes has been related to the electronic effects of the substituents in the tetrapyrrole cycle and spatial distortion of the latter.