Asymmetric synthesis of L-azetidine-2-carboxylic acid and 3-substituted congeners—conformationally constrained analogs of phenylalanine, naphthylalanine, and leucine

Abstract

Enantiopure L-azetidine-2-carboxylic acid, the (3 R)-phenyl, (3 R)-naphthyl and (3 S)-isopropyl analogs were prepared based on a zinc-mediated asymmetric addition of allylic halides to the camphor sultam derivative of glyoxylic acid O-benzyl oxime.