Applied Catalysis A: General, Vol.230, No.1-2, 53-60, 2002
Selective catalysis of mu-oxo-bismetalloporphyrins for 2-methylbutane oxidation with PhIO under mild conditions
Fourteen mu-oxo-bisironporphyrins and nine mu-oxo-bismanganeseporphyrins were synthesized, and their selective catalysis for the oxidation of the secondary and tertiary carbon-hydrogen bonds of 2-methylbutane with PhIO were also studied. The ratio of the relative reaction selectivity of tertiary carbon-hydrogen bonds to secondary carbon-hydrogen bonds was 3:1 when ironporphyrins were used as catalysts, and 4: 1 when manganeseporphyrins were used as catalysts. The research showed that the substituents on the porphyrin rings influenced the catalytic selectivity of metalloporphyrins for the oxidation of the secondary and tertiary carbon-hydrogen bonds as well as the reaction rate. Whether ironporphyrins or manganeseporphyrins, the electron-attracting groups on porphyrin rings increased the catalytic selectivity of metalloporphyrins for the tertiary carbon-hydrogen bonds and the reaction rates, however, the electron-releasing groups increased the catalytic selectivity of metalloporphyrins for secondary carbon-hydrogen bonds, but reduced the reaction rates.