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Spectroscopic characterization and reactivity studies of a mononuclear nonheme Mn(III)-hydroperoxo complex.

ABSTRACT: We report the first example of a mononuclear nonheme manganese(III)-hydroperoxo complex derived from protonation of an isolated manganese(III)-peroxo complex bearing an N-tetramethylated cyclam (TMC) ligand, [Mn(III)(TMC)(OOH)](2+). The Mn(III)-hydroperoxo intermediate is characterized with various spectroscopic methods as well as with density functional theory (DFT) calculations, showing the binding of a hydroperoxide ligand in an end-on fashion. The Mn(III)-hydroperoxo species is a competent oxidant in oxygen atom transfer (OAT) reactions, such as the oxidation of sulfides. The electrophilic character of the Mn(III)-hydroperoxo complex is demonstrated unambiguously in the sulfoxidation of para-substituted thioanisoles.

SUBMITTER: So H

PROVIDER: S-EPMC4156864 | biostudies-other | 2014 Sep

REPOSITORIES: biostudies-other

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Spectroscopic characterization and reactivity studies of a mononuclear nonheme Mn(III)-hydroperoxo complex.

So Hee H Park Young Jun YJ Cho Kyung-Bin KB Lee Yong-Min YM Seo Mi Sook MS Cho Jaeheung J Sarangi Ritimukta R Nam Wonwoo W

Journal of the American Chemical Society 20140820 35

We report the first example of a mononuclear nonheme manganese(III)-hydroperoxo complex derived from protonation of an isolated manganese(III)-peroxo complex bearing an N-tetramethylated cyclam (TMC) ligand, [Mn(III)(TMC)(OOH)](2+). The Mn(III)-hydroperoxo intermediate is characterized with various spectroscopic methods as well as with density functional theory (DFT) calculations, showing the binding of a hydroperoxide ligand in an end-on fashion. The Mn(III)-hydroperoxo species is a competent o ...[more]

PMID: 25116698

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