A current challenge in catalysis is the development of methodologies for the production of bulk chemicals needed at levels of tens and hundreds of thousands of tons per year with the requirement to be produced at very low costs often being in the single-digit US dollar range. At the same time, such methodologies should address challenges raised by current manufacturing processes. Within this research area, a cyanide-free approach toward aliphatic nitriles used as industrial chemicals was developed starting from readily accessible n-alkenes as starting materials available in bulk quantities. This chemoenzymatic process concept is exemplified for the synthesis of nonanenitrile (as an n-/iso-mixture) and runs in water at low to moderate temperatures without the need for any types of cyanide sources. The process is based on a combination of a metal-catalyzed hydroformylation as the world-leading production technology for alkyl aldehydes with an emerging enzyme technology, namely, the recently developed transformation of aldoximes into nitriles through dehydration by means of aldoxime dehydratases. As a missing link, an efficient aldoxime formation with subsequent removal of remaining traces of hydroxylamine as an enzyme-deactivating component was found, which enabled the merging of these three steps, hydroformylation, aldoxime formation, and enzymatic dehydration, toward a nitrile synthesis without the need for purification of intermediates.

A catalytic system was developed to enable the use of industrially available terpenes (e.g., β‐myrcene, β‐farnesene) in hydroaminomethylation to obtain renewable building blocks for surfactants in two steps. This homogeneously catalyzed tandem reaction includes both hydroformylation and enamine condensation steps, followed by hydrogenation. Under the optimized conditions, the Rh/1,2‐bis(diphenylphosphino)ethane catalytic system delivers products in high yields (70 %) after short reaction times (3 h) with unprecedentedly high turnover frequency (TOF) values for the hydroformylation of 1,3‐dienes of over 739 mol mol−1 h−1. This is the highest TOF reported to date for the hydroformylation of a 1,3‐diene. Furthermore, regioselectivities of 97 % and above were observed in the hydroformylation step, which is extraordinarily high for the conversion of 1,3‐dienes. The terpene‐derived amines obtained were further functionalized to quaternary ammonium compounds that were found to show surface activity quite similar to that of industrially available quaternary ammonium compounds. The hydroaminomethylation of terpenes achieves higher step efficiency than industrial means and makes use of an alternative, renewable feedstock to synthesize more environmentally friendly surfactants.

Zwei homogene Palladium‐Katalysatoren zur Hydroesterifizierung des nachwachsenden Rohstoffs 10‐Undecensäuremethylester zum Monomer Dodecandisäuredimethylester werden verglichen. Die Katalysatoren wurden auf ihre Reaktionsraten in thermomorphen Lösungsmittelsystemen untersucht und die Reaktionsparameter optimiert. Anschließend wurde die Abtrennbarkeit der Katalysatoren vom Produkt untersucht und schließlich die Anwendbarkeit des Konzeptes der thermomorphen Lösungsmittelsysteme in dieser Reaktion durch Recyclingexperimente mit beiden Katalysatoren validiert.

A reactive ionic liquid was successfully applied in the homogeneous ruthenium-catalyzed alcohol amination for the first time. Through detailed investigation of the phase behavior and the application of sulfonated ligands, a biphasic system was developed, which fulfils several key points of a sustainable process. This strategy allows, without use of additional volatile organic compounds, a pure product phase to be obtained, enabling the catalyst to be used in repetitive recycling runs. Hence, the productivity of the catalyst was increased fivefold to a cumulative turnover number of more than 2500, which reflects a particularly high catalyst productivity for homogeneous ruthenium-catalyzed alcohol amination.

Efficient utilization of reactive ionic liquid dimcarb for catalyst separation and as the dimethyl amine source in homogeneous Pd-catalysed telomerisation of renewable β-myrcene.