Cp*CoIII-Catalyzed C2-Selective Addition of Indoles to Imines†
Tatsuhiko Yoshino
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
Search for more papers by this authorHideya Ikemoto
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
Search for more papers by this authorCorresponding Author
Dr. Shigeki Matsunaga
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
ACT-C Japan Science and Technology Agency, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206Search for more papers by this authorCorresponding Author
Prof. Dr. Motomu Kanai
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
ERATO, Kanai Life Science Catalysis Project, Japan Science and Technology Agency, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206Search for more papers by this authorTatsuhiko Yoshino
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
Search for more papers by this authorHideya Ikemoto
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
Search for more papers by this authorCorresponding Author
Dr. Shigeki Matsunaga
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
ACT-C Japan Science and Technology Agency, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206Search for more papers by this authorCorresponding Author
Prof. Dr. Motomu Kanai
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206
ERATO, Kanai Life Science Catalysis Project, Japan Science and Technology Agency, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan), Fax: (+81) 3-5684-5206Search for more papers by this authorCp*=1,2,3,4,5-pentamethylcyclopentadienyl; Cp*CoIII=a CoIII complex with one Cp* ligand and other coordinating ligand(s), such as C6H6, a base (OAc), or a substrate (imine or a pyrimidine unit in indoles).
Graphical Abstract
Overriding innate reactivity: The utility of a CoIII catalyst to promote the C2-selective addition of indoles to imines was demonstrated. The CoIII catalyst completely changed the regioselectivity in comparison with simple Lewis acid catalyzed Friedel–Crafts C3-selective addition. High turnover number (TON) of the catalyst, up to 1.8×102 (with s/c=200; see scheme; s/c is the substrate/catalyst ratio), was achieved.
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