title: Anti-Diastereoselective Synthesis of CF3-Containing Spirooxazolines and Spirooxazines via Regiospecific Trifluoromethylative Spirocyclization by Photoredox Catalysis.
abstract: A novel synthesis of CF3-containing spirooxazolines and spirooxazines has been developed. Regiospecific trifluoromethylative spirocyclization (CF3-spirocyclization) of cyclic alkenes bearing an amide pendant mediated by photoredox catalysis is a useful strategy for construction of a C(sp(3))-CF3 bond and an spirooxazoline or spirooxazine ring onto C═C bonds via a single step. The key intermediate is α-CF3-substituted carbocationic species smoothly generated from single-electron-transfer (SET) photoredox processes, which results in diastereoselective spirocyclization. This is the first example of synthesis of CF3-containing spirooxazolines and spirooxazines in anti-fashion with respect to the CF3 group and the oxygen atom of the spirocycles.
authors.affiliation: Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Noto
authors.affiliation: Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
authors.forename: Kazuki
authors.initials: K
authors.lastname: Miyazawa
authors.affiliation: Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Koike
authors.affiliation: Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan.
authors.forename: Munetaka
authors.initials: M
authors.lastname: Akita