In situ spectroscopy in and above manganese catalyzed oxidations

Oxidations are essential component steps in many industrial processes. These range from large scale applications, e.g., the production of plastics and resins, to the small scale applications such as the production of medicines. Oxidations typically make use of catalysts that are responsible for activation of the oxidant and transfer of oxygen atoms to an organic compound. In this thesis two different manganese based complexes, used as such catalysts, are studied to elucidate the mechanisms by which they facilitate oxidation of organic substrates with the oxidant hydrogen peroxide. The aim is to get a better understanding of the working mechanism of these catalyst. Both manganese based complexes show an increasing oxygen concentration in the headspace above the solution, pointing towards the disproportionation of hydrogen peroxide to dioxygen and water. The amount of hydrogen peroxide disproportionation is relevant, since it affects the efficiency of the process. For one of the manganese based complex, a combination of different spectroscopies is used to identify the transformation the manganese complexes undergo. A mixture of several manganese complexes is observed, although these species are considered resting states. For the other manganese based catalyst the concentration is too low to detect. By using other physical organic methods, we can still get information about the active form of the manganese complex.