title: Efficient Enantioselective Synthesis of Oxahelicenes Using Redox/Acid Cooperative Catalysts.
abstract: An efficient and enantioselective synthesis of oxa[9]helicenes has been established via vanadium(V)-catalyzed oxidative coupling/intramolecular cyclization of polycyclic phenols. A newly developed vanadium complex cooperatively functions as both a redox and Lewis acid catalyst to promote the present sequential reaction and afford oxa[9]helicenes in good yields with up to 94% ee.
authors: The Institute of Scientific and Industrial Research (ISIR), Osaka University , Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan.
authors: Makoto
authors: M
authors: Sako
authors: The Institute of Scientific and Industrial Research (ISIR), Osaka University , Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan.
authors: Yoshiki
authors: Y
authors: Takeuchi
authors: Department of Medicinal and Organic Chemistry, School of Pharmacy, Iwate Medical University , Yahaba, Iwate 028-3694, Japan.
authors: Tetsuya
authors: T
authors: Tsujihara
authors: The Institute of Scientific and Industrial Research (ISIR), Osaka University , Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan.
authors: Junpei
authors: J
authors: Kodera
authors: Department of Medicinal and Organic Chemistry, School of Pharmacy, Iwate Medical University , Yahaba, Iwate 028-3694, Japan.
authors: Tomikazu
authors: T
authors: Kawano
authors: The Institute of Scientific and Industrial Research (ISIR), Osaka University , Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan.
authors: Shinobu
authors: S
authors: Takizawa
authors: The Institute of Scientific and Industrial Research (ISIR), Osaka University , Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan.
authors: Hiroaki
authors: H
authors: Sasai