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Consecutive Aryne Generation Strategy for the Synthesis of 1,3-Diarylpyrazoles
Tsuneyuki Kobayashi1, Takamitsu Hosoya1, Suguru Yoshida1
1Laboratory of Chemical Bioscience, Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), 2-3-10 Kanda-Surugadai, Chiyoda-ku, Tokyo 101-0062, Japan.
Abstract:
An efficient method for the synthesis of diverse 1,3-diarylpyrazoles via consecutive aryne generation has been developed. The bisaryne precursors bearing o-iodo- and o-silylaryl triflate moieties were prepared by sequential Suzuki-Miyaura and Chan-Lam-Evans cross-coupling reactions. The selective generation of the first aryne triggered by a silylmethyl Grignard reagent followed by the second aryne generation mediated by a fluoride ion allowed for the synthesis of diverse multisubstituted 1,3-diarylpyrazoles in a modular synthetic manner with various arynophiles.
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