Asymmetric Eschenmoser−Claisen Rearrangement for Anti-β-Substituted γ,δ-Unsaturated Amino Acids
journal contributionposted on 2007-09-27, 00:00 authored by Hongchang Qu, Xuyuan Gu, Zhihua Liu, Byoung J. Min, Victor J. Hruby
Optically active anti-β-substituted γ,δ-unsaturated amino acids are important synthetic building blocks in organic synthesis and for peptidomimetics. A novel asymmetric Eschenmoser−Claisen rearrangement with use of a C2-symmetric chiral auxiliary was developed to generate this type of amino acid. Excellent diastereoselectivities and high enantioselectivities (87−93% ee) were obtained after the chiral auxiliary was removed via iodolactonization/zinc reduction.