Iron and cobalt catalysts in alkene oxidations and polymerizations
Transition-metal complexes, such as those based on cobalt and iron, are used widely as catalysts in chemical oxidations. Non-heme iron compounds are widely applied as catalysts in olefin oxidation, with H2O2 commonly used to produce the reactive iron species needed to oxidize the organic substrates. In these reactions, oxygen is often involved, both being formed upon disproportionation of H2O2 and being consumed through reactions with radical intermediates.
In her thesis, Yan Zhang employed in situ, real-time monitoring using spectroscopic techniques to elucidate the mechanisms involved in iron-catalyzed organic oxidations. Curing (polymerization) of alkene based resins is another representative example of chemical oxidations, in which simultaneous evaluation of product performance and curing kinetics. The associated kinetic parameters are influenced by both material properties and environmental factors, with the concentration of O2 being a key variable. In addition, oxygen introduces challenges in accurately determining these parameters via in situ spectroscopic techniques.
Zhang also investigated the effects of O2 on alkene polymerization, as well as approaches to mitigate its influence using (micro)spectroscopic analysis. The focus of this thesis is understanding the mechanisms in iron and cobalt catalyzed alkene oxidations and polymerizations using inline and offline spectroscopies.