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Updated: Aug 15, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Stereoselective beta-hydroxy-alpha-amino acid synthesis via an ether-directed, palladium-catalysed aza-Claisen
Kate N Fanning1, Andrew G Jamieson, Andrew Sutherland
1WestChem, Department of Chemistry, Joseph Black Building, University of Glasgow, Glasgow, UKG12 8QQ.
Abstract:
A highly diastereoselective synthesis of (2S,3S)-beta-hydroxy-alpha-amino acids has been developed from enantiopure alpha-hydroxy acids using a MOM-ether-directed, palladium(II)-catalysed, aza-Claisen rearrangement of allylic acetimidates to effect the key step. This highly stereoselective process gave allylic amides in diastereomeric ratios of up to 14 : 1. Problems associated with the isolation of 1,3-products (anti-Claisen) from sterically demanding substrates via an insitu palladium(0)-catalysed rearrangement process were overcome by the addition of a re-oxidant, p-benzoquinone, leading to cleaner reactions and improved yields of the 3,3-products (Claisen). The target beta-hydroxy-alpha-amino acids are an important class of natural products that are also components of more complex organic compounds with significant biological properties.
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