title: Intramolecular direct oxygen transfer from oxoferryl porphyrin to a sulfide bond.
abstract: A 1:1 supramolecular complex (met-hemoCD) of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrinatoiron(III) (Fe(III)TPPS) with a per-O-methylated β-cyclodextrin dimer having a -SCH2PyCH2S- (Py = pyridin-3,5-diyl) linker (Py3CD) reacted rapidly with hydrogen peroxide or cumene hydroperoxide in an aqueous solution forming two types of hydroperoxo or alkylperoxo intermediates, ROO-Fe(III)(OH(-))PCD and ROO-Fe(III)(Py)PCD, which underwent rapid homolysis to the corresponding ferryloxo species, namely, O═Fe(IV)(OH(-))PCD and O═Fe(IV)(Py)PCD, respectively. For the O═Fe(IV)(OH(-))PCD species, the iron-oxo oxygen facing the linker gradually transferred to the nearby sulfide bond on the linker, forming the sulfoxidized Py3CD (Py3CD-O)/Fe(II)TPPS complex, which then bound dioxygen in air forming an oxy-ferrous complex, O2-Fe(II)TPPS/Py3CD-O. In contrast, the O═Fe(IV)(Py)PCD species, in which the iron-oxo oxygen was located on the opposite side of the sulfide bond on the linker across the porphyrin ring, was reduced to the resting state (met-hemoCD) by the surroundings without any oxidation of the Py3CD linker.
authors: Department of Molecular Chemistry and Biochemistry, Doshisha University , Kyotanabe, Kyoto 610-0321, Japan.
authors: Takunori
authors: T
authors: Ueda
authors: Hiroaki
authors: H
authors: Kitagishi
authors: Koji
authors: K
authors: Kano
mesh_terms: D007501:Iron / Q000737:chemistry*; D008665:Metalloporphyrins / Q000138:chemical synthesis / Q000737:chemistry*; D015394:Molecular Structure; D010100:Oxygen / Q000737:chemistry*; D011166:Porphyrins / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*
chemical_list: D008665:Metalloporphyrins; D011166:Porphyrins; D013440:Sulfides; D007501:Iron; D010100:Oxygen