Mechanism of catalytic oxygenation of alkanes by halogenated iron porphyrins

Science. 1994 May 27;264(5163):1311-3. doi: 10.1126/science.8191283.

Abstract

Halogenation of an iron porphyrin causes severe saddling of the macrocyclic structure and a large positive shift in the iron(III)/(II) redox couple. Although pre-halogenated iron(II) porphyrins such as Fe(TFPPBr8) [H2TFPPBr8, beta-octabromo-tetrakis(pentafluorophenyl)-porphyrin] are relatively resistant to autoxidation, they rapidly reduce alkyl hydroperoxides. These and related reactivity studies suggest that catalysis of alkane oxygenation by Fe(TFPPBr8)Cl occurs through a radical-chain mechanism in which the radicals are generated by oxidation and reduction of alkyl hydroperoxides.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alkanes / chemistry*
  • Catalysis
  • Oxidation-Reduction
  • Pentanes / chemistry*
  • Porphyrins / chemistry*

Substances

  • Alkanes
  • Pentanes
  • Porphyrins
  • 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(pentafluorophenyl)porphyrinato-iron(III)
  • 3-methylpentane