An investigation of electrode oxidation processes of (tetraphenylporphinato)manganese(III) perchlorate, (TPP)Mn(III)ClO4, was carried out during the titration of chloride anions by conventional cyclic voltammetry, thin-layer cyclic voltammetry and spectroelectrochem. It was demonstrated that in the presence of one equivalent amount of Cl1-, the first one electron oxidation reaction corresponds to the Mn(III)/cation radical oxidation, and the 2nd one electron oxidation corresponds to the cation radical/dication generation followed by an isoporphyrin formation reaction, however in the presence of 2 equiv amount of Cl1-, the first one electron oxidation of Mn(III) gives Mn(IV) porphyrin and the 2nd one electron oxidation generates cation radicals of Mn(IV) followed by an isoporphyrin formation reactions. Mechanisms of these redox processes are postulated.

Key words: ULTRAVIOLET SPECTROPHOTOMETRY, OXIDATION, REACTION MECHANISM, CHLORINE ION, MANGANESE COMPLEX, CYCLOVOLTAMGRAPH