One-Pot γ-Lactonization of Homopropargyl Alcohols via Intramolecular Ketene Trapping
Daichi Yamane, Haruna Tanaka, Akihiro Hirata, Yumiko Tamura, Daichi Takahashi, Yusuke Takahashi, Tohru Nagamitsu* and Masaki Ohtawa*
*School of Pharmacy, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641, Japan, Email: nagamitsutpharm.kitasato-u.ac.jp, ohtawampharm.kitasato-u.ac.jp
D. Yamane, H. Tanaka, A. Hirata, Y. Tamura, D. Takahashi, Y. Takahashi, T. Nagamitsu, M. Ohtawa, Org. Lett., 2021, 23, 2831-2835.
DOI: 10.1021/acs.orglett.1c00840
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Abstract
An alkyne deprotonation/boronation/oxidation sequence enables a one-pot γ-lactonization of homopropargyl alcohols. Oxidation of the generated alkynyl boronate affords the corresponding ketene intermediate, which is trapped by the adjacent hydroxy group to furnish the γ-lactone.
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proposed mechanism
Key Words
ID: J54-Y2021