title: Efficient intramolecular cyclizations of phenoxyethynyl diols into multisubstituted α,β-unsaturated lactones.
abstract: AgOTf-catalyzed intramolecular cyclization of phenoxyethynyl diols proceeded under mild conditions to afford the multisubstituted α,β-unsaturated-γ-lactones in 55-98% yields. This method was also applicable to the synthesis of α,β-unsaturated-δ-lactones. A similar cyclization proceeded when AgOTf was replaced with a stoichiometric amount of N-bromosuccinimide to furnish the α-bromo-substituted α,β-unsaturated lactones.
authors.affiliation: School of Pharmaceutical Sciences, University of Shizuoka, 52-1, Yada, Suruga-ku, Shizuoka, Shizuoka 422-8526, Japan. egi@u-shizuoka-ken.ac.jp
authors.forename: Masahiro
authors.initials: M
authors.lastname: Egi
authors.forename: Yuya
authors.initials: Y
authors.lastname: Ota
authors.forename: Yuka
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Kaori
authors.initials: K
authors.lastname: Shimizu
authors.forename: Kenji
authors.initials: K
authors.lastname: Azechi
authors.forename: Shuji
authors.initials: S
authors.lastname: Akai
mesh_terms: D002384:Catalysis; D003500:Cyclization; D007783:Lactones / Q000138:chemical synthesis* / Q000737:chemistry; D008698:Mesylates / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D007783:Lactones; D008698:Mesylates; C012077:trifluoromethanesulfonic acid