title: Asymmetric chroman synthesis via an intramolecular oxy-Michael addition by bifunctional organocatalysts.
abstract: Cinchona-alkaloid-urea-based bifunctional organocatalysts facilitate the catalytic asymmetric synthesis of chroman derivatives via an intramolecular oxy-Michael addition reaction. Phenol derivatives bearing an easily available (E)-α,β-unsaturated ketone or a thioester moiety are useful substrates for the title transformation. This method represents a facile synthesis of various optically active 2-substituted chromans in high yield.
authors.affiliation: Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Kyotodaigaku-Katsura, Nishikyo, Kyoto 615-8510, Japan. asano.keisuke.5w@kyoto-u.ac.jp matsubara.seijiro.2e@kyoto-u.ac.jp.
authors.forename: Ryota
authors.initials: R
authors.lastname: Miyaji
authors.forename: Keisuke
authors.initials: K
authors.lastname: Asano
authors.forename: Seijiro
authors.initials: S
authors.lastname: Matsubara
mesh_terms: D000470:Alkaloids / Q000737:chemistry*; D002384:Catalysis; D002839:Chromans / Q000138:chemical synthesis* / Q000737:chemistry; D002929:Cinchona / Q000737:chemistry*; D008968:Molecular Conformation; D014508:Urea / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D002839:Chromans; D014508:Urea