Mechanism of Alkene, Alkane, and Alcohol Oxidation with H2O2 by an in Situ Prepared Mn-II/Pyridine-2-carboxylic Acid Catalyst

Pattama Saisaha, Jia Jia Dong, Tim G. Meinds, Johannes W. de Boer, Ronald Hage, Francesco Mecozzi, Johann B. Kasper, Wesley R. Browne*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

34 Citations (Scopus)
86 Downloads (Pure)


The oxidation of alkenes, alkanes, and alcohols with H2O2 is catalyzed efficiently using an in situ prepared catalyst comprised of a MnII salt and pyridine-2-carboxylic acid (PCA) together with a ketone in a wide range of solvents. The mechanism by which these reactions proceed is elucidated, with a particular focus on the role played by each reaction component: i.e., ketone, PCA, MnII salt, solvent, etc. It is shown that the equilibrium between the ketone cocatalysts, in particular butanedione, and H2O2 is central to the catalytic activity observed and that a gem-hydroxyl-hydroperoxy species is responsible for generating the active form of the manganese catalyst. Furthermore, the oxidation of the ketone to a carboxylic acid is shown to antecede the onset of substrate conversion. Indeed, addition of acetic acid either prior to or after addition of H2O2 eliminates a lag period observed at low catalyst loading. Carboxylic acids are shown to affect both the activity of the catalyst and the formation of the gem-hydroxyl-hydroperoxy species. The molecular nature of the catalyst itself is explored through the effect of variation of MnII and PCA concentration, with the data indicating that a MnII:PCA ratio of 1:2 is necessary for activity. A remarkable feature of the catalytic system is that the apparent order in substrate is 0, indicating that the formation of highly reactive manganese species is rate limiting.

Original languageEnglish
Pages (from-to)3486-3495
Number of pages10
JournalACS Catalysis
Issue number6
Publication statusPublished - Jun-2016


  • manganese
  • oxidation
  • catalysis
  • Raman spectroscopy
  • epoxidation
  • IRON
  • FE

Cite this