An alternative stereoselective synthesis of trans-(2R,3R)-3-hydroxypipecolic acid

The enantioselective synthesis of trans-(2R,3R)-3-hydroxypipecolic acid 1b is presented, starting from O-protected methyl mandelate as chiral source. The synthesis involved a regioselective intramolecular nucleophilic substitution of an azido epoxide as the key step .