title: Olefin cis-Dihydroxylation and Aliphatic C-H Bond Oxygenation by a Dioxygen-Derived Electrophilic Iron-Oxygen Oxidant.
abstract: Many iron-containing enzymes involve metal-oxygen oxidants to carry out O2-dependent transformation reactions. However, the selective oxidation of C-H and C=C bonds by biomimetic complexes using O2 remains a major challenge in bioinspired catalysis. The reactivity of iron-oxygen oxidants generated from an Fe(II)-benzilate complex of a facial N3 ligand were thus investigated. The complex reacted with O2 to form a nucleophilic oxidant, whereas an electrophilic oxidant, intercepted by external substrates, was generated in the presence of a Lewis acid. Based on the mechanistic studies, a nucleophilic Fe(II)-hydroperoxo species is proposed to form from the benzilate complex, which undergoes heterolytic O-O bond cleavage in the presence of a Lewis acid to generate an Fe(IV)-oxo-hydroxo oxidant. The electrophilic iron-oxygen oxidant selectively oxidizes sulfides to sulfoxides, alkenes to cis-diols, and it hydroxylates the C-H bonds of alkanes, including that of cyclohexane.
authors.affiliation: Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata-700032 (India).
authors.forename: Sayanti
authors.initials: S
authors.lastname: Chatterjee
authors.affiliation: Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, 2A & 2B Raja S. C. Mullick Road, Jadavpur, Kolkata-700032 (India). ictkp@iacs.res.in.
authors.forename: Tapan Kanti
authors.initials: TK
authors.lastname: Paine
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D001561:Benzilates / Q000737:chemistry; D002244:Carbon / Q000737:chemistry; D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry; D005296:Ferrous Compounds / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D007501:Iron / Q000737:chemistry*; D058116:Lewis Acids / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*
chemical_list: D000475:Alkenes; D001561:Benzilates; D056831:Coordination Complexes; D005296:Ferrous Compounds; D058116:Lewis Acids; D002244:Carbon; D006859:Hydrogen; D007501:Iron; D010100:Oxygen
keywords: Lewis acids; dioxygen; electrophilic oxidants; iron; oxidation