Comparative study of catalytic activity of some biomimetic models of cytochrome P450 in oxidation of olefins with tetra-n-butylammonium periodate: Electron-rich Mn-porphyrins versus the electron-deficient ones

Oxidation of a wide range of cyclic and acyclic olefins with tetra-n-butylammonium periodate shows different orders of catalytic activity for a series of electron-rich and electron-deficient Mn-porphyrins in oxidation of various alkenes. While the Mn(III) complex of meso-tetra(4-thiomethoxyphenyl)porphyrin, MnT(4-SCH3P)P(OAc), has the highest activity among the series, the β tetra-brominted derivative shows the lowest catalytic efficiency for the oxidation of the used olefins with the exception of cis- and trans-stilbene. The results clearly show that the electron-withdrawing effects of meso- and β-substituents may increase or decrease the catalytic activity of Mn-porphyrins in the case of different olefins.

Oxidation of a wide range of cyclic and acyclic olefins with tetra-n-butylammonium periodate in the presence of imidazole and a series of electron-rich and electron-deficient Mn(III) meso-tetraarylporphyrins shows higher or comparable catalytic efficiencies for the electron-rich Mn-porphyrins compared with the electron-deficient ones.Figure optionsDownload as PowerPoint slideResearch highlights
► Electron-rich Mn(III)-porphyrins as efficient as the electron-deficient ones.
► Unusual instability of Mn(III) meso-tetraarylporphyrin with para-NO2 groups.
► Different substituent dependence of catalytic activity for various olefins.
► High efficiency of MnT(4-SCH3P)P(OAc) in oxidation of olefins with periodate.