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Updated: Aug 14, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Continuous homogeneous asymmetric transfer hydrogenation of ketones: lessons from kinetics
Lasse Greiner1, Stephan Laue, Andreas Liese
1Institut für Technische und Makromolekulare Chemie, RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany. greiner@itmc.rwth-aachen.de
Abstract:
Is polymer enlargement of homogeneous catalysts a tedious task? Is not batch operation with homogeneous catalysts the optimum performance point for homogeneous catalysis? Is kinetic modelling relevant to more than academic questions in homogeneous catalysis? Can all answers for a given system be answered satisfactory? In the authors' view, answers to these questions are no, no, yes, and depends. Polymer enlargement allowed the continuous operation of transfer hydrogenation in a chemical membrane reactor with total turnover numbers of up to 2.6 x 10(3) and a space-time yield of 0.58 kg L(-1) d(-1) with an enantiomeric ratio of 26.8 (enantiomeric excess 92.8 %) for a conversion level of 80 %. This was predicted from simulation conducted with a model from kinetic batch experiments adopted for continuous application. These simulations for the polymer-enlarged and the unmodified catalyst show that achieving comparable performance cannot be obtained by batch operation.
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