title: Asymmetric Synthesis of 2H-Azirine 2-Carboxylate Esters.
abstract: 2H-Azirine 2-carboxylate esters (5), the smallest unsaturated nitrogen heterocycle, are readily prepared in enantiomerically pure form via the base-induced elimination of sulfenic acid (RSOH) from nonracemic N-sulfinylaziridine 2-carboxylate esters (4). Optimum yields were obtained when the aziridine was treated with TMSCl at -95 degrees C followed by LDA, which was attributed to the improved leaving group ability of an silicon-oxonium species. By using this new methodology the first asymmetric syntheses of the marine cytotoxic antibiotics (R)-(-)- and (S)-(+)-dysidazirine (2) were accomplished.
authors.affiliation: Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122.
authors.forename: Franklin A.
authors.initials: FA
authors.lastname: Davis
authors.forename: Hu
authors.initials: H
authors.lastname: Liu
authors.forename: Chang-Hsing
authors.initials: CH
authors.lastname: Liang
authors.forename: G. Venkat
authors.initials: GV
authors.lastname: Reddy
authors.forename: Yulian
authors.initials: Y
authors.lastname: Zhang
authors.forename: Tianan
authors.initials: T
authors.lastname: Fang
authors.forename: Donald D.
authors.initials: DD
authors.lastname: Titus