Van Marum colloquium by prof.dr. Evgeny Pidko from Delft University of Technology on "Death and life of homogeneous carbonyl reduction catalysts: navigating condition space towards superior catalytic performance".

Abstract:
Catalytic reduction of carbonyl moieties in ketones and esters to their corresponding alcohols are fundamental to the production of high value fine-chemicals. In recent years, traditional Ru and Ir catalysts have been complemented by novel first-row transition metal catalysts due to their favorable sustainability, economics, and reduced toxicity.[1] The practical implementation of such catalysts based on e.g. Fe or Mn is often hampered by their limited stability under the catalytic conditions. Understanding the catalytic and deactivation paths for such systems is key to tailoring their properties towards enhanced and sustained catalytic performance. In this lecture, I will discuss the importance and challenges of understanding the chemistry of catalyst deactivation for the development of practical catalytic technologies with the examples of our recent studies on Mn catalysis for selective reduction of carbonyl-containing compounds. [2,3]

Conventionally, the performance of homogeneous catalyst is interpreted in terms of the molecular structures and electronic properties of the organometallic compounds they originate from. In practice, the catalyst systems are highly complex, multicomponent, and intrinsically multifunctional. Their behaviour is only partially controlled by the chemistry of “catalyst molecule” (e.g., nature of the metal site, ligand structure and composition, intrinsic reactivity of the complex). It should rather be viewed as a complex function of a much wider range of parameters such as the activation procedure, the presence of promotors, solvent type, and the selected conditions (T, p, medium composition). [3] The position within such a complex condition space defines the preference of the catalytic species to live and drive the catalytic cycles of the desired chemical transformations or to die via one of the competing deactivation channels. An insight into the underlying mechanisms and their condition-dependencies could be obtained through the combination of operando spectroscopy, kinetic studies [3] and automated expert-bias free computational mechanistic analysis [4], which would help navigate this vast condition space and boost the efficiency and lifetime of the 3d metal-based catalyst systems.

More information found here.

The "Van Marum Colloquia" is a collaborative lecture series between the LION and LIC institutes, focusing on fundamental and applied surface science.