An N-bridged high-valent diiron-oxo species on a porphyrin platform that can oxidize methane

Nat Chem. 2012 Dec;4(12):1024-9. doi: 10.1038/nchem.1471. Epub 2012 Oct 14.


High-valent oxo-metal complexes are involved in key biochemical processes of selective oxidation and removal of xenobiotics. The catalytic properties of cytochrome P-450 and soluble methane monooxygenase enzymes are associated with oxo species on mononuclear iron haem and diiron non-haem platforms, respectively. Bio-inspired chemical systems that can reproduce the fascinating ability of these enzymes to oxidize the strongest C-H bonds are the focus of intense scrutiny. In this context, the development of highly oxidizing diiron macrocyclic catalysts requires a structural determination of the elusive active species and elucidation of the reaction mechanism. Here we report the preparation of an Fe(IV)(µ-nitrido)Fe(IV) = O tetraphenylporphyrin cation radical species at -90 °C, characterized by ultraviolet-visible, electron paramagnetic resonance and Mössbauer spectroscopies and by electrospray ionization mass spectrometry. This species exhibits a very high activity for oxygen-atom transfer towards alkanes, including methane. These findings provide a foundation on which to develop efficient and clean oxidation processes, in particular transformations of the strongest C-H bonds.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chlorobenzoates / chemistry
  • Metalloporphyrins / chemistry*
  • Methane / chemistry*
  • Nitrogen / chemistry*
  • Oxidation-Reduction
  • Spectrometry, Mass, Electrospray Ionization


  • Chlorobenzoates
  • Metalloporphyrins
  • 3-chloroperbenzoic acid
  • Nitrogen
  • Methane

Associated data

  • PubChem-Substance/144186570
  • PubChem-Substance/144186571
  • PubChem-Substance/144186572
  • PubChem-Substance/144186573