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Updated: Apr 11, 2026
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Highly Enantioselective Hydrogenation of Imines Catalyzed by Chiral Macrocyclic Boranes
Ru Zhang1,2, Wei Meng1,2, Xiangqing Feng1,2
1Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
Abstract:
In this paper, we report a macrocyclic alkene-derived borane catalyst for the asymmetric hydrogenation of imines. A wide range of imines was successfully converted to chiral amines in 80-97% yields and 40-97% ee. The macrocyclic framework is indispensable for excellent catalytic activity and enantioselectivity. A gram-scale reaction with 0.2 mol % catalyst loading achieved a turnover number of 485, the highest reported to date for frustrated Lewis pair-catalyzed asymmetric imine hydrogenation.
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