Synthesis of terminally protected (S)-β3-H-DOPA by Arndt-Eistert homologation: an approach to crowned β-peptides

Terminally protected Boc-(S)-β3-H-DOPA-OMe has been synthesized from l-DOPA by the Arndt-Eistert homologation procedure. During the synthesis, the side-chain catechol group was temporarily protected by benzylation.