Spectroscopic Characterization and Reactivity Studies of a Mononuclear Nonheme Mn(III)–Hydroperoxo Complex
نویسندگان
چکیده
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.
منابع مشابه
Nonheme ferric hydroperoxo intermediates are efficient oxidants of bromide oxidation.
This work presents the first combined experimental and computational study that gives evidence of the electrophilic reactivity of a nonheme iron(III)-hydroperoxo species. We show that in contrast to their heme counterparts the nonheme iron(III)-hydroperoxo complexes are catalytically much more active and even more so than nonheme iron(IV)-oxo species.
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