Novel stereospecific dehydration of β-hydroxy-α-amino acids using Martinʹs sulfurane

The stereospecific dehydration of threo-N-acyl-β-hydroxy-α-amino acid derivatives was performed using Martinʹs sulfurane to give (Z)-α,β-dehydroamino acids, while erythro-N-acyl-β-hydroxy-α-amino acid amides were converted to 4,5-trans-oxazolines using analogous reaction conditions.