Visible Light-Promoted Deracemization of α-Amino Aldehyde by Synergistic Chiral Primary Amine and Hypervalent Iodine
Tianrun Pan1, Xieyang Jiang1, Mouxin Huang2
1Center of Basic Molecular Science, Department of Chemistry, Tsinghua University, Beijing 100084, China.
Abstract:
α-Amino aldehydes, as versatile chiral synthons, are easily racemized under normal acid or base conditions, seriously limiting their synthetic potentials. We report herein an effective deracemization of α-amino aldehydes by a synergistic chiral primary amine and hypervalent iodine catalysis under visible light. The developed catalytic system allows for the on-demand production of α-Boc- or Cbz-protected amino aldehydes with high enantioselectivity. Mechanistic studies verified a photochemical Z-E isomerization mechanism that drives the deracemization process.
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