PhD student Ilse Denekamp of the Heterogeneous Catalysis and Sustainable Chemistry research group has won the Best Poster Award by public vote at the Dutch national chemistry conference CHAINS 2018 earlier this month.
The poster describes her work on catalytic non-radical air oxidation of cyclohexene. This allylic oxidation keeps the double bond while creating a new alcohol or carbonyl function. However, the reaction is far from straightforward. Oxygen has a high oxygen activation barrier due to resonance stabilisation, and often unwanted over-oxidation products appear.
To overcome these hurdles Ilse Denekamp studied the allylic oxidation of cyclohexene with O2 under mild conditions in the presence of transition‐metal catalysts consisting of nanometric metal oxide particles supported on porous N‐doped carbons. In particular the Co@N:C and Cu@N:C catalysts showed a high performance. The research revealed that while the former involves a traditional free-radical process, the latter facilitates activation of oxygen at the catalyst surface followed by a surface reaction with adsorbed cyclohexenyl hydroperoxide molecules.
The research has been published as an open-access paper in ChemCatChem:
Ilse M. Denekamp, Martijn Antens, Thierry K. Slot and Prof. Gadi Rothenberg: Selective Catalytic Oxidation of Cyclohexene with Molecular Oxygen: Radical Versus Nonradical Pathways. ChemCatChem 2018, 10, 1035–1041