title: A Structurally Characterized Nonheme Cobalt-Hydroperoxo Complex Derived from Its Superoxo Intermediate via Hydrogen Atom Abstraction.
abstract: Bubbling O2into a THF solution of CoII(BDPP) (1) at -90 °C generates an O2adduct, Co(BDPP)(O2) (3). The resonance Raman and EPR investigations reveal that 3 contains a low spin cobalt(III) ion bound to a superoxo ligand. Significantly, at -90 °C, 3 can react with 2,2,6,6-tetramethyl-1-hydroxypiperidine (TEMPOH) to form a structurally characterized cobalt(III)-hydroperoxo complex, CoIII(BDPP)(OOH) (4) and TEMPO•. Our findings show that cobalt(III)-superoxo species are capable of performing hydrogen atom abstraction processes. Such a stepwise O2-activating process helps to rationalize cobalt-catalyzed aerobic oxidations and sheds light on the possible mechanism of action for Co-bleomycin.
authors.affiliation: Department of Chemistry and Instrumentation Center, National Taiwan Normal University , Taipei 11677, Taiwan.|Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan.
authors.forename: Chun-Chieh
authors.initials: CC
authors.lastname: Wang
authors.affiliation: Department of Chemistry and Instrumentation Center, National Taiwan Normal University , Taipei 11677, Taiwan.
authors.forename: Hao-Ching
authors.initials: HC
authors.lastname: Chang
authors.affiliation: Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan.
authors.forename: Yei-Chen
authors.initials: YC
authors.lastname: Lai
authors.affiliation: Max-Planck Institut für Chemische Energiekonversion , Mülheim an der Ruhr D-45470, Germany.
authors.forename: Huayi
authors.initials: H
authors.lastname: Fang
authors.affiliation: Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan.
authors.forename: Chieh-Chin
authors.initials: CC
authors.lastname: Li
authors.affiliation: Department of Chemistry and Instrumentation Center, National Taiwan Normal University , Taipei 11677, Taiwan.
authors.forename: Hung-Kai
authors.initials: HK
authors.lastname: Hsu
authors.affiliation: Department of Chemistry and Instrumentation Center, National Taiwan Normal University , Taipei 11677, Taiwan.
authors.forename: Zong-Yan
authors.initials: ZY
authors.lastname: Li
authors.affiliation: Department of Chemistry, Washington University , St. Louis, Missouri 63130, United States.
authors.forename: Tien-Sung
authors.initials: TS
authors.lastname: Lin
authors.affiliation: Department of Chemistry and Instrumentation Center, National Taiwan Normal University , Taipei 11677, Taiwan.
authors.forename: Ting-Shen
authors.initials: TS
authors.lastname: Kuo
authors.affiliation: Max-Planck Institut für Chemische Energiekonversion , Mülheim an der Ruhr D-45470, Germany.
authors.forename: Frank
authors.initials: F
authors.lastname: Neese
authors.affiliation: Max-Planck Institut für Chemische Energiekonversion , Mülheim an der Ruhr D-45470, Germany.
authors.forename: Shengfa
authors.initials: S
authors.lastname: Ye
authors.affiliation: Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan.
authors.forename: Yun-Wei
authors.initials: YW
authors.lastname: Chiang
authors.affiliation: Department of Chemistry, National Sun Yat-sen University , Kaohsiung 80424, Taiwan.
authors.forename: Ming-Li
authors.initials: ML
authors.lastname: Tsai
authors.affiliation: Department of Chemistry, National Tsing Hua University , Hsinchu 30013, Taiwan.
authors.forename: Wen-Feng
authors.initials: WF
authors.lastname: Liaw
authors.affiliation: Department of Chemistry and Instrumentation Center, National Taiwan Normal University , Taipei 11677, Taiwan.
authors.forename: Way-Zen
authors.initials: WZ
authors.lastname: Lee