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Conversion of two stereocenters to one or two chiral axes: atroposelective synthesis of 2,3-diarylbenzoindoles.

ABSTRACT: Central-to-axial chirality conversion provides efficient access to axially chiral compounds, and several examples regarding the conversion of one, two or four stereocenters to one axis have been reported. Herein, we report the conversion of two stereocenters to one or two chiral axes for the first time. In this study, a new class of enantiomerically enriched 2,3-diarylbenzoindoles was efficiently synthesized using a chiral phosphoric acid-catalyzed [3 + 2] formal cycloaddition and a mild DDQ oxidation strategy. Moreover, a speculative model of the central-to-axial chirality conversion outcome was proposed based on preliminary mechanistic studies and DFT calculations. Potentially, using this strategy, useful chiral phosphine ligand can be synthesized smoothly (99% ee).

SUBMITTER: Hu YL

PROVIDER: S-EPMC6657404 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Conversion of two stereocenters to one or two chiral axes: atroposelective synthesis of 2,3-diarylbenzoindoles.

Hu Yu-Long YL Wang Zhe Z Yang Hui H Chen Jie J Wu Zi-Bo ZB Lei Yibo Y Zhou Ling L

Chemical science 20190520 28

Central-to-axial chirality conversion provides efficient access to axially chiral compounds, and several examples regarding the conversion of one, two or four stereocenters to one axis have been reported. Herein, we report the conversion of two stereocenters to one or two chiral axes for the first time. In this study, a new class of enantiomerically enriched 2,3-diarylbenzoindoles was efficiently synthesized using a chiral phosphoric acid-catalyzed [3 + 2] formal cycloaddition and a mild DDQ oxi ...[more]

PMID: 31391898

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