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Updated: Aug 5, 2025
Enzymatic Cascade Reactions for the Synthesis of Chiral Amino Alcohols from L-lysine
Published on: February 16, 2018
Asymmetric Hydrogenation of α-Amino Esters into Optically Active β-Amino Alcohols through Dynamic Kinetic Resolution
Hiroki Ishikawa1, Taiga Yurino2, Ryo Komatsu3
1Takasago International Corporation, Corporate Research & Development Division, 1-4-11 Nishi-yawata, Hiratsuka City, Kanagawa 254-0073, Japan.
Abstract:
Racemic α-substituted α-amino esters were hydrogenated into enantioenriched β-amino alcohols through dynamic kinetic resolution with chiral ruthenabicyclic complexes. The reaction was carried out with a substrate/catalyst molar ratio of 200-1000 under 15 atm of H2 at 25 °C to afford a variety of β-substituted β-aminoethanols in up to 96% ee (24 examples). The mechanistic studies including deuteration experiments suggested that the reaction proceeds with 1,2-hydride migration of the α-amino acetalate intermediate into the α-hydroxy imine followed by the continuous reduction of the imino compound, affording the amino alcohol product.
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