Highly oxidized iron complexes of N-methyltetra-p-tolylporphyrin

Article abstract of DOI:10.1021/ja00032a044

Two different, highly oxidized iron complexes of N-methyltetra-p-tolylporphyrin (N-MeTTPH) have been detected by ¹H and ²H NMR spectroscopy after oxidation with m-chloropcroxybenzoic acid. In CH₂Cl₂/CH₃OH (4:1, v/v) in the presence of sodium methoxide (N-MeTTP)Fe^IICl is converted to (N-MeTTP)Fe^II(OCH₃) and then to (CH₃O)(N-MeTTP)Fe^IV = O upon addition of the peroxyacid. The latter is observable over the temperature range -90 to 0°C, has a magnetic susceptibility of 2.9 μB (S = 1 ), and is reduced by phenyldimethylphosphine to (N-MeTTP)Fe^II(OCH₃). In the absence of sodium methoxide, (N-MeTTP)Fe^IICl is oxidized by the peroxyacid to form a very unstable species observable from -90 to -75°C whose ¹H NMR spectrum shows large hyperfine shifts for the meso aryl substituents that are consistent with the presence of a π-N- methylporphyrin radical in the product.