Reactivity of hydroperoxide bound to a mononuclear non-heme iron site.
The first isolation and spectroscopic characterization of the mononuclear hydroperoxo-iron(III) complex [Fe(H(2)bppa)(OOH)](2+) (2) and the stoichiometric oxidation of substrates by the mononuclear iron-oxo intermediate generated by its decomposition have been described. The purple species 2 obtained from reaction of [Fe(H(2)bppa)(HCOO)](ClO(4))(2) with H(2)O(2) in acetone at -50 degrees C gave characteristic UV-vis (lambda(max) = 568 nm, epsilon = 1200 M(-1) cm(-1)), ESR (g = 7.54, 5.78, and 4.25, S = (5)/(2)), and ESI mass spectra (m/z 288.5 corresponding to the ion, [Fe(bppa)(OOH)](2+)), which revealed that 2 is a high-spin mononuclear iron(III) complex with a hydroperoxide in an end-on fashion. The resonance Raman spectrum of 2 in d(6)-acetone revealed two intense bands at 621 and 830 cm(-1), which shifted to 599 and 813 cm(-1), respectively, when reacted with (18)O-labeled H(2)O(2). Reactions of the isolated (bppa)Fe(III)-OOH (2) with various substrates (single turnover oxidations) exhibited that the iron-oxo intermediate generated by decomposition of 2 is a nucleophilic species formulated as [(H(2)bppa)Fe(III)-O*].
Wada
Akira
A
Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya 466-8555, Japan.
Ogo
Seiji
S
Nagatomo
Shigenori
S
Kitagawa
Teizo
T
Watanabe
Yoshihito
Y
Jitsukawa
Koichiro
K
Masuda
Hideki
H
D000473:Alkanes / Q000737:chemistry*; D002384:Catalysis; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry* / Q000302:isolation & purification; D006418:Heme / Q000737:chemistry* / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000737:chemistry*; D007501:Iron / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D019159:Nonheme Iron Proteins / Q000737:chemistry*; D010084:Oxidation-Reduction; D021241:Spectrometry, Mass, Electrospray Ionization; D013059:Spectrum Analysis, Raman
D000473:Alkanes; D005290:Ferric Compounds; D019159:Nonheme Iron Proteins; D006418:Heme; D003577:Cytochrome P-450 Enzyme System; D006861:Hydrogen Peroxide; D007501:Iron