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Regioselective/electro-oxidative intermolecular [3 + 2] annulation for the preparation of indolines.

ABSTRACT: Compared with the reported intramolecular electro-oxidative cyclization of alkenyl amines or vinyl anilines for the preparation of pyrrolidines or indolines, the intermolecular version is less studied. Herein, this electrochemical intermolecular oxidative annulation of anilines and alkenes for the preparation of indolines proceeded under external oxidant-free conditions. The most noteworthy achievement of our work is the facile generation of indolines with quaternary centers at the 2-position. In addition, alkenes and anilines bearing various functional groups can be well tolerated. Remarkably, electrolyte-free conditions were used in an electrochemical flow cell, which shows the application potential of this method.

SUBMITTER: Wang Q

PROVIDER: S-EPMC8150106 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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Regioselective/electro-oxidative intermolecular [3 + 2] annulation for the preparation of indolines.

Wang Qingqing Q Wang Pan P Gao Xinlong X Wang Dan D Wang Shengchun S Liang Xingan X Wang Liwei L Zhang Heng H Lei Aiwen A

Chemical science 20200115 8

Compared with the reported intramolecular electro-oxidative cyclization of alkenyl amines or vinyl anilines for the preparation of pyrrolidines or indolines, the intermolecular version is less studied. Herein, this electrochemical intermolecular oxidative annulation of anilines and alkenes for the preparation of indolines proceeded under external oxidant-free conditions. The most noteworthy achievement of our work is the facile generation of indolines with quaternary centers at the 2-position. I ...[more]

PMID: 34123309

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