Dataset Information


Protonation of a peroxodiiron(III) complex and conversion to a diiron(III/IV) intermediate: implications for proton-assisted O-O bond cleavage in nonheme diiron enzymes.

ABSTRACT: Oxygenation of a diiron(II) complex, [Fe(II)(2)(?-OH)(2)(BnBQA)(2)(NCMe)(2)](2+) [2, where BnBQA is N-benzyl-N,N-bis(2-quinolinylmethyl)amine], results in the formation of a metastable peroxodiferric intermediate, 3. The treatment of 3 with strong acid affords its conjugate acid, 4, in which the (?-oxo)(?-1,2-peroxo)diiron(III) core of 3 is protonated at the oxo bridge. The core structures of 3 and 4 are characterized in detail by UV-vis, Mössbauer, resonance Raman, and X-ray absorption spectroscopies. Complex 4 is shorter-lived than 3 and decays to generate in ~20% yield of a diiron(III/IV) species 5, which can be identified by electron paramagnetic resonance and Mössbauer spectroscopies. This reaction sequence demonstrates for the first time that protonation of the oxo bridge of a (?-oxo)(?-1,2-peroxo)diiron(III) complex leads to cleavage of the peroxo O-O bond and formation of a high-valent diiron complex, thereby mimicking the steps involved in the formation of intermediate X in the activation cycle of ribonucleotide reductase.

SUBMITTER: Cranswick MA 

PROVIDER: S-EPMC3462276 | BioStudies | 2012-01-01

REPOSITORIES: biostudies

Similar Datasets

2008-01-01 | S-EPMC2736334 | BioStudies
2010-01-01 | S-EPMC2812653 | BioStudies
2006-01-01 | S-EPMC2501110 | BioStudies
1000-01-01 | S-EPMC2736468 | BioStudies
2020-01-01 | S-EPMC7136037 | BioStudies
2012-01-01 | S-EPMC3298377 | BioStudies
2018-01-01 | S-EPMC5920527 | BioStudies
2009-01-01 | S-EPMC2758929 | BioStudies
2017-01-01 | S-EPMC5765857 | BioStudies
2011-01-01 | S-EPMC3149837 | BioStudies