An In-Depth Mechanistic Study of Ru-Catalysed Aqueous Methanol Dehydrogenation and Prospects for Future Catalyst Design

Autor: Monica Trincado, Vivek Sinha, Hansjörg Grützmacher, Evert Jan Meijer, Bas de Bruin, Nitish Govindarajan
Přispěvatelé: Molecular Simulations (HIMS, FNWI), HIMS Other Research (FNWI), Homogeneous and Supramolecular Catalysis (HIMS, FNWI), Sustainable Chemistry, HCSC+ (HIMS, FNWI)
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: ChemCatChem, 12 (9)
ChemCatChem, 12(9), 2610-2621. Wiley
ISSN: 1867-3880
1867-3899
Popis: Herein we provide mechanistic insights into the dehydrogenation of aqueous methanol catalysed by the [Ru(trop2dae)] complex (which is in‐situ generated from [Ru(trop2dad)], trop2dad=1,4‐bis(5H‐dibenzo[a,d]cyclohepten‐5‐yl)‐1,4‐diazabuta‐1,3‐diene), established by density functional theory based molecular dynamics (DFT‐MD) and static DFT calculations incorporating explicit solvent molecules. The aqueous solvent proved to participate actively in various stages of the catalytic cycle including the catalyst activation process, and the key reaction steps involving C−H activation and hydrogen production. The aqueous solvent forms an integral part of the reactive system for the C−H activation steps in the [Ru(trop2dae)] system, with strong hydrogen bond interactions with the anionic oxygen (RO−, R=CH3, CH2OH, HCO) and hydride moieties formed along the reaction pathway. In contrast to the [Ru(trop2dad)] catalyst, C−H activation and hydrogen production does not proceed via a metal‐ligand cooperative pathway for the [Ru(trop2dae)] system. The pKa of the coordinated amine donors in these complexes provides a rationale for the divergent reactivity, and the obtained mechanistic information provides new guidelines for the rational design of active and additive free catalytic systems for aqueous methanol dehydrogenation.
ChemCatChem, 12 (9)
ISSN:1867-3880
ISSN:1867-3899
Databáze: OpenAIRE