Biomimetic alcohol oxidations by an iron(III) porphyrin complex: relevance to cytochrome P-450 catalytic oxidation and involvement of the two-state radical rebound mechanism.
The systematic oxidation reactions of a wide range of alcohols have been carried out by using an iron porphyrin complex in order to understand their relation to cytochrome P-450 enzymes and to have a practical application to organic synthesis. The iron porphyrin complex catalyzed efficiently alcohol oxidation to the respective carbonyl compound via a high-valent iron-oxo porphyrin intermediate ((Porp)Fe=O+). Several mechanistic studies such as isotope 18O labeling, deuterium isotope effect, linear free energy relationship, and ring-opening of radical clock substrate, have suggested that the alcohol is oxidized by a sequence of reactions involving an alpha-hydroxyalkyl radical intermediate and oxygen rebound to form the gem-diol, dehydration of which yields the carbonyl compounds. Moreover, it has been proposed that a two-state reactivity mechanism can also be adopted for alcohol oxidation reactions in iron porphyrin model systems as exhibited by P-450 enzymes.
Han
Jung Hee
JH
Department of Fine Chemistry, Seoul National University of Technology, Seoul, 139-743, Korea.
Yoo
Sang-Kun
SK
Seo
Jin Soo
JS
Hong
Sung Jin
SJ
Kim
Seok Kyu
SK
Kim
Cheal
C
D000438:Alcohols / Q000378:metabolism*; D001665:Binding Sites; D032701:Biomimetics; D002384:Catalysis; D003511:Cyclohexanols / Q000737:chemistry; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D003903:Deuterium / Q000378:metabolism; D005609:Free Radicals; D007501:Iron / Q000737:chemistry* / Q000378:metabolism; D008665:Metalloporphyrins / Q000378:metabolism*; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism
D000438:Alcohols; D003511:Cyclohexanols; D005609:Free Radicals; D008665:Metalloporphyrins; D003577:Cytochrome P-450 Enzyme System; D003903:Deuterium; D007501:Iron; D010100:Oxygen