Volume 62, Issue 21 e202302638
Research Article

Facile Access to Cyclopropylboronates via Stereospecific Deborylative Cyclization: A Leaving Group-Assisted Activation of Geminal Diborons

Xin-Yi Chen

Xin-Yi Chen

Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062 China

These authors contributed equally to this work.

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Feng-Chen Gao

Feng-Chen Gao

Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062 China

These authors contributed equally to this work.

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Peng-Fei Ning

Peng-Fei Ning

Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062 China

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Yi Wei

Yi Wei

Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062 China

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Prof. Dr. Kai Hong

Corresponding Author

Prof. Dr. Kai Hong

Shanghai Engineering Research Center of Molecular Therapeutics and New Drug Development, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062 China

Shanghai Frontiers Science Center of Molecule Intelligent Syntheses, School of Chemistry and Molecular Engineering, East China Normal University, 3663 N Zhongshan Road, Shanghai, 200062 China

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First published: 24 March 2023
Citations: 16

Graphical Abstract

A transition metal-free deborylative cyclization strategy led to the efficient synthesis of racemic and enantioenriched cyclopropylboronates. The cyclization of geminal-bis(boronates) bearing a leaving group was highly diastereoselective and stereospecific, tolerating various functional groups and heterocycles. Mechanistic studies indicated that the leaving group at the γ-position significantly promoted the activation of the gem-diboron moiety.

Abstract

Herein we reported a transition metal-free deborylative cyclization strategy, based on which two routes have been developed, generating racemic and enantioenriched cyclopropylboronates. The cyclization of geminal-bis(boronates) bearing a leaving group was highly diastereoselective, tolerating a few functional groups and applicable to heterocycles. When optically active epoxides were used as the starting materials, enantioenriched cyclopropylboronates could be efficiently prepared with >99 % stereospecificity. Mechanistic studies showed that the leaving group at the γ-position played a crucial role and significantly promoted the activation of the gem-diboron moiety.

Conflict of interest

The authors declare no conflict of interest.

Data Availability Statement

The data that support the findings of this study are available in the supplementary material of this article.

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