title: Catalytic and Enantioselective Synthesis of Chiral Multisubstituted Tribenzothiepins by Intermolecular Cycloadditions.
abstract: The first catalytic and highly enantioselective synthesis of tribenzothiepin derivatives was achieved. Two types of intermolecular cycloadditions using either diphenyl-sulfide-tethered diynes or 2-phenyl sulfanylbenzene-tethered diynes with a monoalkyne successfully gave chiral multisubstituted tribenzothiepins in good to excellent ee values under mild conditions. The inversion energy of this saddle-shaped molecule was calculated by measurement of the racemization rate of chiral tribenzothiepins using the Eyring kinetic equation under heating conditions. The present protocol could also be used to prepare a chiral tribenzoselenepin.
authors.affiliation: Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo, 169-8555, Japan.
authors.forename: Yu-Ki
authors.initials: YK
authors.lastname: Tahara
authors.affiliation: Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo, 169-8555, Japan.
authors.forename: Riku
authors.initials: R
authors.lastname: Matsubara
authors.affiliation: Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo, 169-8555, Japan.
authors.forename: Akihito
authors.initials: A
authors.lastname: Mitake
authors.affiliation: Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo, 169-8555, Japan.
authors.forename: Tatsuki
authors.initials: T
authors.lastname: Sato
authors.affiliation: International Center for Science and Engineering Programs (ICSEP), Waseda University, Shinjuku, Tokyo, 169-8555, Japan.
authors.forename: Kyalo Stephen
authors.initials: KS
authors.lastname: Kanyiva
authors.affiliation: Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku, Tokyo, 169-8555, Japan. tshibata@waseda.jp.|JST, ACT-C, Kawaguchi, Saitama, 332-0012, Japan. tshibata@waseda.jp.
authors.forename: Takanori
authors.initials: T
authors.lastname: Shibata
keywords: chirality; cycloaddition; enantioselectivity; rhodium; synthetic methods