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Updated: Jun 17, 2025
Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
Small-Molecule-Based Strategy for Mitigating Deactivation of Chiral Lewis Acid Catalysis
Fangqiu Lu1, Taku Kitanosono1, Yasuhiro Yamashita1
1Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Abstract:
Chiral Lewis acid catalysts are widely used in organic synthesis due to their diverse applications. However, their high Lewis acidity makes them susceptible to deactivation by basic Lewis reagents and water. Here, we present a novel strategy for mitigating this deactivation using small molecules. By incorporating weakly coordinating anions into the secondary coordination sphere of the metal center, we designed a highly reusable chiral Lewis acid complex. This complex exhibits excellent thermal stability and allows for the use of electron-poor nucleophiles in the reactions. Spectroscopic and titration studies confirmed the robustness of the optimized complex. This work provides valuable insights for overcoming the limitations of chiral Lewis acids in Lewis basic environments, expanding their potential for chemical synthesis.
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