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Updated: Jun 13, 2025

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Understanding Heterogeneously Catalyzed Hydrogenation of Carbonyl Compounds Through Keto-Enol Tautomerization
Jingtai Li1, Carsten Schröder2, Marvin Schmidt2
1State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China.
None:
The possibility of low-barrier hydrogenation of carbonyl compounds via keto-enol tautomerization as the initial step is a highly debated question in catalysis research. Here, a comprehensive description is provided, supported by theoretical and experimental techniques, of surface-assisted keto-enol tautomerization and subsequent hydrogenation of carbonyl compounds to alcohols. The crucial role of the ketone-ketone dimers as key reaction intermediates is elucidated, in which one ketone species undergoes a low-barrier tautomerization to form a stable ketone-enol dimer. This phenomenon arises from the strong intermolecular interactions within the dimers and the substantial charge-transfer between the adsorbates and the surface. Remarkably, the reduction of the barrier is primarily attributed to the charge-transfer from the inner HOMO-1 orbital. This work explores the atomic details underlying the tautomerization reaction, contributing to the rational design of high-performance metal catalysts for low-barrier hydrogenation of carbonyl compounds.
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