Reversal of diastereoselectivity of the reaction of chiral boron and titanium enolates with nitrones via N-acyloxyiminium intermediates. Asymmetric synthesis of diastereomeric α-substituted β-amino acids

Article abstract of DOI:10.1246/cl.1999.795

Reaction of nitrones and acyl halides gives N-acyloxyiminium species, which are more reactive toward soft carbon nucleophiles than nitrones. Addition of chiral enolates to the N-acyloxyiminium species gave N-hydroxy-β-amino acid derivatives highly diaster