title: Structural and spectroscopic characterization of metastable thiolate-ligated manganese(III)-alkylperoxo species.
abstract: Metastable Mn-peroxo species are proposed to form as key intermediates in biological oxidation reactions involving O(2) and C-H bond activation. The majority of these have yet to be spectroscopically characterized, and their inherent instability, in most cases, precludes structural characterization. Cysteinate-ligated metal-peroxos have been shown to form as reactive intermediates in both heme and nonheme iron enzymes. Herein we report the only examples of isolable Mn(III)-alkylperoxo species, and the first two examples of structurally characterized synthetic thiolate-ligated metal-peroxos. Spectroscopic data, including electronic absorption and IR spectra, and ESI mass spectra for (16)O vs (18)O-labeled metastable Mn(III)-OOR (R = (t)Bu, Cm) are discussed, as well as preliminary reactivity.
authors.affiliation: Department of Chemistry, University of Washington, Seattle, Washington 98195, United States.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Coggins
authors.forename: Julie A
authors.initials: JA
authors.lastname: Kovacs
mesh_terms: D003545:Cysteine / Q000737:chemistry; D008345:Manganese / Q000737:chemistry*; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D021241:Spectrometry, Mass, Electrospray Ionization; D013055:Spectrophotometry, Infrared; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D009942:Organometallic Compounds; D013438:Sulfhydryl Compounds; D008345:Manganese; D003545:Cysteine