Iron Porphyrin Complexes Reversible Formation of Iodosylbenzene±Iron Porphyrin Intermediates in the Reaction of Oxoiron(iv) Porphyrin p-Cation Radicals and Iodobenzene**
نویسندگان
چکیده
High-valent oxoiron(iv) porphyrin p-cation radicals 2 are generally accepted to be the key reactive intermediates in a variety of oxidation reactions by heme-containing enzymes such as cytochromes P450, peroxidases, and catalases.[1,2] Extensive studies with synthetic iron(iii) porphyrin complexes and various terminal oxidants have shown that 2 is generated by heterolytic O X bond cleavage of [(Porp)FeIII-O-X]þ (1) [path A in Eq. (1)].[3] In contrast, there are only two reported instances of the reverse reaction, O X bond formation between 2 and X [path B in Eq. (1)], as biomimetic examples of haloperoxidases.[4] One is the oxo transfer from an oxomanganese(v) porphyrin complex to bromide (Br ),[4a] and the other is the generation of a [(Porp)FeIII-OCl] complex in the reaction of 2 and Cl .[4b] 1⁄2ðPorpÞFe þ þOX Ð 1⁄2ðPorpÞFe-O-X þ ð1ÞG A
منابع مشابه
Reversible formation of iodosylbenzene-iron porphyrin intermediates in the reaction of oxoiron(IV) porphyrin pi-cation radicals and iodobenzene.
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