0000000000380102

AUTHOR

Ken Okamoto

showing 2 related works from this author

Dehydrogenation versus Oxygenation in Two-Electron and Four-Electron Reduction of Dioxygen by 9-Alkyl-10-methyl-9,10-dihydroacridines Catalyzed by Mo…

2004

Dehydrogenation of 10-methyl-9,10-dihydroacridine (AcrH(2)) by dioxygen (O(2)) proceeds efficiently, accompanied by the two-electron and four-electron reduction of O(2) to produce H(2)O(2) and H(2)O, which are effectively catalyzed by monomeric cobalt porphyrins and cofacial dicobalt porphyrins in the presence of perchloric acid (HClO(4)) in acetonitrile (MeCN) and benzonitrile (PhCN), respectively. The cobalt porphyrin catalyzed two-electron reduction of O(2) also occurs efficiently by 9-alkyl-10-methyl-9,10-dihydroacridines (AcrHR; R = Me, Et, and CH(2)COOEt) to yield 9-alkyl-10-methylacridinium ion (AcrR+) and H(2)O(2). In the case of R = Bu(t) and CMe(2)COOMe, however, the catalytic two…

Metalloporphyrinschemistry.chemical_elementElectronsReaction intermediatePhotochemistryBiochemistryMedicinal chemistryCatalysisCatalysischemistry.chemical_compoundColloid and Surface ChemistryDehydrogenationPerchloric acidAlkylchemistry.chemical_classificationPerchloratesChemistryCobaltGeneral ChemistryNADPorphyrinKineticsBenzonitrileAcridinesHydrogenationOxidation-ReductionCobaltJournal of the American Chemical Society
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Mechanism of four-electron reduction of dioxygen to water by ferrocene derivatives in the presence of perchloric acid in benzonitrile, catalyzed by c…

2004

The selective two-electron reduction of dioxygen occurs in the case of a monocobalt porphyrin [Co(OEP)], whereas the selective four-electron reduction of dioxygen occurs in the case of a cofacial dicobalt porphyrin [Co(2)(DPX)]. The other cofacial dicobalt porphyrins [Co(2)(DPA), Co(2)(DPB), and Co(2)(DPD)] also catalyze the two-electron reduction of dioxygen, but the four-electron reduction is not as efficient as in the case of Co(2)(DPX). The micro-superoxo species of cofacial dicobalt porphyrins were produced by the reactions of cofacial dicobalt(II) porphyrins with dioxygen in the presence of a bulky base and the subsequent one-electron oxidation of the resulting micro-peroxo species by…

Reaction mechanismchemistry.chemical_elementGeneral ChemistryPhotochemistryBiochemistryPorphyrinCatalysisCatalysischemistry.chemical_compoundBenzonitrileElectron transferColloid and Surface ChemistryReaction rate constantchemistryPerchloric acidCobaltJournal of the American Chemical Society
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