The catalytic behaviors of Mn(III)-porphyrin in the oxidation of aromatic aldehydes with NaOCl as oxidant under two-phase condition have been investigated. When TPPMn(III)OAc (TPP = tetraphenylporphyrin), TPPFe(III)Cl, TPPCo(II), and TPPNi(II) were used as catalysts, only TPPMn(III)OAc and TPPFeCl exhibit distinct activities. With TPPMn(III)OAc as catalyst, UV - visible spectral changes of the fourth band from 425 nm to 478 nm were observed during the course of the oxygen transfer, suggesting that oxo-manganese(V) porphyrin is the key element for the oxygenation of aldehydes. Electron withdrawing para-substituents of TPPMnOAc lead to an increase in activities and stabilities. Electron withdrawing ortho substituents increase the stabilities of manganese porphyrins, but decrease their activities.

Key words: OXIDATION, CATALYSIS, ACETATE, METAL COMPLEX, CHLORIDE, PORPHYRIN, IRON COMPLEX, SODIUM HYPOCHLORITE, BENZALDEHYDE, MANGANESE COMPLEX