| Abstract
| - We have obtained evidence that acylperoxo-iron(III) porphyrin complexes 1a are involved as reactivehydroxylating intermediates in the hydroxylation of alkanes by m-chloroperoxybenzoic acid (m-CPBA) catalyzedby electron-deficient iron(III) porphyrin complexes containing chloride as an anionic axial ligand in a solventmixture of CH2Cl2 and CH3CN at −40 °C. In addition to the intermediacy of 1a, oxoiron(IV) porphyrin cationradical complexes 2 are formed as the reactive hydroxylating intermediates in the alkane hydroxylations bym-CPBA catalyzed by the iron(III) porphyrin complexes containing triflate (CF3SO3-) as an anionic axialligand under the same reaction conditions. In line with the recent proposal by Newcomb, Coon, Vaz, andco-workers for cytochrome P-450 reactions, these results suggest that two distinct electrophilic oxidants suchas 1a and 2 effect the alkane hydroxylations in iron porphyrin models, depending on the reaction conditionssuch as the nature of the anionic axial ligands of iron(III) porphyrin complexes.
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