Ring-fluorinated isoquinoline and quinoline synthesis: intramolecular cyclization of o-cyano- and o-isocyano-beta,beta-difluorostyrenes.
o-Cyano-beta,beta-difluorostyrenes react with organolithiums selectively at the cyano carbon to generate the corresponding sp(2) nitrogen anions, which in turn undergo intramolecular replacement of the vinylic fluorine to afford 3-fluoroisoquinolines. Similarly, the reaction of beta,beta-difluoro-o-isocyanostyrenes with organomagnesiums or -lithiums generates the corresponding sp(2) carbanions on the isocyano carbon. Subsequent cyclization via substitution of the fluorine leads to 3-fluoroquinolines. [reaction: see text]
Ichikawa
Junji
J
Department of Chemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. junji@chem.s.u-tokyo.ac.jp
Wada
Yukinori
Y
Miyazaki
Hiroyuki
H
Mori
Takashi
T
Kuroki
Hiroyuki
H
D003500:Cyclization; D006845:Hydrocarbons, Fluorinated / Q000138:chemical synthesis*; D007546:Isoquinolines / Q000138:chemical synthesis*; D009570:Nitriles / Q000737:chemistry*; D011804:Quinolines / Q000138:chemical synthesis*; D013343:Styrenes / Q000737:chemistry*
D006845:Hydrocarbons, Fluorinated; D007546:Isoquinolines; D009570:Nitriles; D011804:Quinolines; D013343:Styrenes