A First Example of Oxidation of Manganese(III) Porphyrin in Sulfuric Acid Solutions

摘要

We studied spectrophotometrically the state and reactions of the Mn(III) complex with 2,7,12,17-tetra- methyl-3,8,13,18-tetra(n-butyl)porphine [(Cl)MnP] (I) in acid solutions.The spectrum of I in acetic acid (AcOH) is similar to that in toluene,which indicates that the Mn(III) complex is stable in AcOH.However, its spectrum in concentrated H_2SO_4 [lambda_(max),nm (log epsilon): 427 (5.03),571 (3.93),620 (3.82),768 (3.79)] differs essentially from the known spectra of porphyrins and their Mn(III) complexes in acids.