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Updated: Jul 5, 2025

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Asymmetric Hydrogenation of α-Alkyl-Substituted β-Keto Esters and Amides through Dynamic Kinetic Resolution
Taiga Yurino1, Ryo Nishihara2, Toshihisa Yasuda3
1Division of Applied Chemistry and Frontier Chemistry Center, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido 060-8628, Japan.
Abstract:
Asymmetric hydrogenation of α-alkyl-substituted β-keto esters and amides with the DIPSkewphos/3-AMIQ-Ru(II) catalyst system through dynamic kinetic resolution was examined. A series of β-keto esters and amides with a simple or functionalized α-alkyl group were applicable to this reaction, affording the α-substituted β-hydroxy esters and amides in ≥99% ee (anti/syn ≥ 99:1) in many cases. The 5 g scale reaction was readily achieved. The mode of enantio- and diastereoselection in the transition state model was proposed.
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