Aliphatic hydroxylation catalyzed by iron(III) porphyrins

• Published in: Journal of the American Chemical Society Vol. 114; no. 4; pp. 1308 - 1312
• Main Authors: Traylor, Teddy G, Hill, Kenneth W, Fann, Wen Pang, Tsuchiya, Shinji, Dunlap, Beth E
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 01.02.1992; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Multidisciplinary; Exact sciences and technology; Kinetics and mechanisms; Organic chemistry; Physical Sciences; Reactivity and mechanisms; Science & Technology; HEMINS; SUBSTITUENTS; COMPLEXES; EPOXIDATIONS; IRON; MECHANISMS; CYTOCHROME-P-450; Deuterium; Catalytic reaction; Hydrocarbon; Hydroxylation; Aliphatic compound; Nitrogen heterocycle; Saturated compound; Organic ligand; Hydrogen Isotopes; Stereochemistry; Macrocycle; Isotope effect; Iron III Complexes; Bicyclic compound; Reaction mechanism; Metalloporphyrin; Rate constant
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja00030a028

Hydroxylation of aliphatic hydrocarbons with oxidants such as iodosobenzene can be effectively catalyzed with highly halogenated iron(III) porphyrins such as iron(III) tetrakis(2,6-dichlorophenyl)octabromoporphyrin. Hydroxylation of norbornane and tetraexodeuterionorbornane using this catalyst afforded good yields of products which consisted of 86:13: < 1 and 84:16: < 1 ratios of exo-norbornan-2-ol, endo-norbornan-2-ol, and 2-norbornanone, respectively. In the latter case both D3 and D4 exo and endo alcohols but only D3 ketone were obtained. The primary isotope effect is 5. These results show that the reaction involves loss of stereochemistry and has a large isotope effect; the results are in agreement with those from a previous study of the same compounds using the enzyme cytochrome P-450. As in that case, this hydroxylation proceeds through a free-radical cage process. The hemin catalysis leads to a loss of stereospecificity similar to that in the enzyme-catalyzed reaction.