title: Thio-Claisen rearrangement used in preparing anti-β-functionalized γ,δ-unsaturated amino acids: scope and limitations.
abstract: Multifunctionalized amino acids, especially amino acids with unsaturation, are important, demanding building blocks in peptide chemistry. Here we present a summary of our most recent study using the thio-Claisen rearrangement for the synthesis of anti-β-functionalized γ,δ-unsaturated amino acids. Investigations on scope, limitations, chemoselectivities and stereoselectivities regarding an FeBr(3)-catalyzed allylation strategy and a thio-enolate dianion formation strategy for asymmetric thio-Claisen rearrangement are documented. An explanation of the chirality crossover observed between the Eschenmoser-Claisen rearrangement and the thio-Claisen rearrangement is proposed. Novel optically active N(α)-protected amino acids with biologically interesting functional groups were prepared for the first time.
authors.affiliation: Department of Chemistry and Biochemistry, University of Arizona, 1306 East University Boulevard, Tucson, Arizona 85721, USA.
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Liu
authors.forename: Sukeshi J
authors.initials: SJ
authors.lastname: Mehta
authors.forename: Kwang-Soo
authors.initials: KS
authors.lastname: Lee
authors.forename: Bryan
authors.initials: B
authors.lastname: Grossman
authors.forename: Hongchang
authors.initials: H
authors.lastname: Qu
authors.forename: Xuyuan
authors.initials: X
authors.lastname: Gu
authors.forename: Gary S
authors.initials: GS
authors.lastname: Nichol
authors.forename: Victor J
authors.initials: VJ
authors.lastname: Hruby
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D001965:Bromides / Q000737:chemistry; D002384:Catalysis; D008958:Models, Molecular; D008968:Molecular Conformation; D013237:Stereoisomerism; D013455:Sulfur / Q000737:chemistry*
chemical_list: D000596:Amino Acids; D001965:Bromides; D013455:Sulfur