Effect of l-cysteine on the oxidation of cyclohexane catalyzed by manganeseporphyrin

In the oxidation of cyclohexane by MnTPP, l-cysteine could moderately improve the catalytic activity of MnTPP and significantly increase the selectivity of cyclohexanol. The l-cysteine may perform dual roles in the catalytic oxidation. [Display omitted] Effect of l-cysteine as the cocatalyst on the oxidation of cyclohexane by tert-butylhydroperoxide (TBHP) catalyzed by manganese tetraphenylporphyrin (MnTPP) has been investigated. The results showed that l-cysteine could moderately improve the catalytic activity of MnTPP and significantly increase the selectivity of cyclohexanol. Different from imidazole and pyridine, the l-cysteine may perform dual roles in the catalytic oxidation of cyclohexane. Besides as the axial ligand for MnTPP, the l-cysteine could also react with cyclohexyl peroxide formed as the intermediate to produce alcohol as the main product.