Synthesis of Branch-Type 3-Allylindoles from N-Alkyl-N-cinnamyl-2-ethynylaniline Derivatives Using π-Allylpalladium
Kohei Watanabe1, Keita Nakano2, Hayato Sato2
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Abstract:
The reaction of N-alkyl-N-cinnamyl-2-ethynylaniline derivatives 1 via annulation and aza-Claisen-type rearrangement easily afforded corresponding branch-type 3-allylindoles 2 with high regioselectivities in good yields using π-allylpalladium chloride complex as a catalyst.
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