Mechanistic Insights in “CO-free” Carbonylation Reactions as Revealed by Quantitative 2D Correlation X-ray and Infrared Spectroscopy
The research project deals with the characterization of catalytic reactions in particular with the characterization of “CO-free” carbonylation reactions utilizing X-ray absorption spectroscopy and vibrational spectroscopy. The characterization is supported by a new quantitative way to evaluate 2D correlation spectra.
Carbonylations reactions involving carbon monoxide surrogates like formaldehyde or formic acid can be a vital stepping stone to a carbon neutral circular economy. A circular economy describes a closed production cycle where resources are converted multiple times to different products. For a chemical process this approach implies an activation and recycling of combustion products like carbon dioxide (CO2) and carbon monoxide (CO). Unfortunately, CO is highly toxic and flammable. Thus, it is appropriate to start the synthesis route from more harmless CO surrogates like formaldehyde.
To fully understand the atomic reaction pathways involved in “CO-free” carbonylation reactions it is important to study the catalytic reaction during in-situ or operando conditions using sophisticated spectroscopic techniques. One of these available techniques is X-ray absorption spectroscopy. By combining X-ray absorption spectroscopy with vibrational spectroscopy it is possible to look into changes in oxidation states and local environments as well as in changing molecular structures. The results of this characterization can be used to design energy and resource efficient chemical processes in the future.
2D correlation spectroscopy is an analysis technique to analyze the perturbation-dependent behavior of spectral changes. Unfortunately, 2D correlation spectra are usually analyzed in a highly subjective way by looking at the 2D correlation patterns. This analysis approach completely discards the quantitative results from the 2D correlation analysis. Within the proposed project a new quantitative analysis approach for 2D correlation spectra shall be developed. A quantitative analysis approach for 2D correlation spectra will enable an in-depth evaluation of established theories and will also enable a quantification of the influence of e.g. the (de-)stabilizing influence of an additional ligand system to the catalytic reaction.
In summary, the present research project will on one hand deal with the spectroscopic characterization of “CO-free” carbonylation reactions utilizing X-ray absorption and vibrational spectroscopy and on the other hand it will deal with the development of a new quantitative 2D correlation analysis approach. The project will lead to innovative ways in the characterization of catalytic reactions.