Two concise routes for the synthesis of the title amino acid have been developed. The first route employs Seebach's general approach [Seebach, D.; Lelais, G.; Micuch, P.; Josien- Lefebvre, D.; Rossi, F. Helv. Chim. Acta2004, 87, 3131] with Arndt Eistert homologation of Boc-O-allyl α-serine as the key process. The second route employs an approach using Boc- α-aspartic acid as a starting material [Salzmann, TN; Ratcliffe, RW; Christensen, BG; ...