Abstract
Chemical reactions inside single crystals are quite rare because crystallinity is difficult to retain owing to atomic rearrangements. Protein crystals in general have a high solvent content. This allows for some molecular flexibility, which makes it possible to trap reaction intermediates of enzymatic reactions without disrupting the crystal lattice. A similar approach has not yet been fully implemented in the field of inorganic chemistry. Here, we have combined model chemistry and protein X-ray crystallography to study the intramolecular aromatic dihydroxylation by an arene-containing protein-bound iron complex. The bound complex was able to activate dioxygen in the presence of a reductant, leading to the formation of catechol as the sole product. The structure determination of four of the catalytic cycle intermediates and the end product showed that the hydroxylation reaction implicates an iron peroxo, generated by reductive O2 activation, an intermediate already observed in iron monooxygenases. This strategy also provided unexpected mechanistic details such as the rearrangement of the iron coordination sphere on metal reduction.
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Change history
14 October 2010
In the version of this Article originally published online, an in-house error led to the omission of one of the beamlines from the Acknowledgements. This has now been corrected in all versions of the Article.
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Acknowledgements
We thank the Agence Nationale pour la Recherche for financial support (ANR 08-CP2D-12 and ANR NT05-2 41493). We also thank Colette Lebrun (SCIB, CEA-Grenoble) for ESI-MS measurements and the CEA, the University Joseph Fourier and the CNRS for institutional support. We thank the staff from the beamlines ID14, BM-30a, ID23-eh2 and cryobench ID29s of the European Synchrotron Radiation Facility in Grenoble, France.
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Cavazza, C., Bochot, C., Rousselot-Pailley, P. et al. Crystallographic snapshots of the reaction of aromatic C–H with O2 catalysed by a protein-bound iron complex. Nature Chem 2, 1069–1076 (2010). https://doi.org/10.1038/nchem.841
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DOI: https://doi.org/10.1038/nchem.841
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