A highly stereoselective entry to α-hydroxy carboxylic acids using d-fructose diacetonide as a chiral auxiliary

Protected α-hydroxy carboxylic acids were synthesized in moderate yield and high diastereoselectivity by alkylation of glycolate ester enolates using a d-fructose-derived chiral auxiliary. The new chiral center was assigned the (R)-configuration based upon comparisons to the literature. Both enantiomers of the auxiliary are readily available.