Direct C4-Benzylation of Indoles via Tandem Benzyl
Claisen/Cope Rearrangements

Abe, Takumi; Kosaka, Yuta; Asano, Miku; Harasawa, Natsuki; Mishina, Akane; Nagasue, Misato; Sugimoto, Yuri; Katakawa, Kazuaki; Sueki, Shunsuke; Anada, Masahiro; Yamada, Koji

doi:10.1021/acs.orglett.8b04120.s001

ol8b04120_si_001.pdf (43.16 MB)

Direct C4-Benzylation of Indoles via Tandem Benzyl Claisen/Cope Rearrangements

journal contribution

posted on 2019-01-23, 21:19 authored by Takumi Abe, Yuta Kosaka, Miku Asano, Natsuki Harasawa, Akane Mishina, Misato Nagasue, Yuri Sugimoto, Kazuaki Katakawa, Shunsuke Sueki, Masahiro Anada, Koji Yamada

A novel direct C4 benzylation of indoles utilizing 2-benzyloxyindoles has been developed to access 4-benzyl-2-oxindoles. This strategy involves the in situ formation of isotoluene intermediates via benzyl Claisen rearrangements, which undergoes Cope rearrangement and aromatization. The method provides the desired products in moderate to high yields and shows good functional group tolerance.