Ruthenium Complexes with PYA Pincer Ligands for Catalytic Transfer Hydrogenation of Challenging Substrates

Authors

  • Philipp Melle Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012 Bern, SCS-DSM Award for best poster presentation in Inorganic & Coordination Chemistry
  • Martin Albrecht Departement für Chemie und Biochemie, Universität Bern, Freiestrasse 3, CH-3012 Bern;, Email: martin.albrecht@dcb.unibe.ch

DOI:

https://doi.org/10.2533/chimia.2019.299

Keywords:

Homogenous catalysis, Ligand design, Pyridylidene amides, Transfer hydrogenation

Abstract

Here we highlight the potential of a series of ruthenium complexes with tridentate N,N,N pincer-type ligands featuring two pyridylidene amide (PYA) moieties in the ligand skeleton. They were successfully applied in transfer hydrogenation of ketones and C=C double bonds. Rational ligand design was key for increasing the catalytic performance in the reduction of challenging substrates such as potentially chelating acetylpyridines. The specific reaction profiles indicate catalyst poisoning via imine coordination as well as N,O-bidentate coordination of the substrate or the product. Approaches to mitigate this inhibition are presented. Furthermore, these PYA pincer ruthenium complexes accomplish the selective reduction of the C=C over C=O bond of ?,?-unsaturated ketones such as benzylideneacetone, while other ?,?-unsaturated ketones such as trans-chalcone predominantly underwent oxidative C=C bond cleavage.

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Published

2019-04-24

How to Cite

[1]
P. Melle, M. Albrecht, Chimia 2019, 73, 299, DOI: 10.2533/chimia.2019.299.