RESUMO
Mononuclear manganese(III) peroxido complexes are candidates for the reaction intermediates in manganese containing proteins, such as manganese superoxide dismutase (Mn-SOD) etc. In this study, manganese(III) peroxido complexes [Mn(O2)(L3)] and [Mn(O2)(L10)] ligated by anionic N3 type ligands with sterically hindered substituents, hydrotris(3-tertiary butyl-5-isopropyl-1-pyrazolyl)borate (L3-) and hydrotris(3-adamantyl-5-isopropyl-1-pyrazolyl)borate (L10-), respectively, were structurally characterized. These complexes are the first examples of structurally characterized five-coordinate manganese(III) peroxido complexes. Their characteristic ν(OO) and ν(MnO) stretchings were determined by using H218O2 for the first time. Theoretical calculations were performed to obtain further insight into their structural parameters. The decomposed products were obtained as [{MnIII(µ-O)(L3)}2MnIV] and [MnIII(OH){L10(O)}] from [Mn(O2)(L3)] and [Mn(O2)(L10)], respectively.