title: Hydrolytic enantioselective protonation of cyclic dienyl esters and a β-diketone with chiral phase-transfer catalysts.
abstract: Hydrolytic enantioselective protonation of dienyl esters and a β-diketone catalyzed by phase-transfer catalysts are described. The latter reaction is the first example of an enantio-convergent retro-Claisen condensation. Corresponding various optically active α,β-unsaturated ketones having tertiary chiral centers adjacent to carbonyl groups were obtained in good to excellent yields and enantiomeric ratios (83-99%, up to 97.5:2.5 er).
authors.affiliation: Department of Chemistry, Graduate School of Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Yamamoto
authors.forename: Daichi
authors.initials: D
authors.lastname: Gokuden
authors.forename: Ayano
authors.initials: A
authors.lastname: Nagai
authors.forename: Takashi
authors.initials: T
authors.lastname: Kamachi
authors.forename: Kazunari
authors.initials: K
authors.lastname: Yoshizawa
authors.forename: Akiyuki
authors.initials: A
authors.lastname: Hamasaki
authors.forename: Tamao
authors.initials: T
authors.lastname: Ishida
authors.forename: Makoto
authors.initials: M
authors.lastname: Tokunaga
mesh_terms: D002384:Catalysis; D003512:Cyclohexanones / Q000138:chemical synthesis* / Q000737:chemistry; D004988:Ethers, Cyclic / Q000737:chemistry*; D006868:Hydrolysis; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D003512:Cyclohexanones; D004988:Ethers, Cyclic; D007659:Ketones