Single-Step Synthesis of Atropisomers with Vicinal C-C and C-N Diaxes by Cobalt-Catalyzed Atroposelective C-H Annulation

Bing-Jie Wang; Guo-Xiong Xu; Zong-Wei Huang; Xu Wu; Xin Hong; Qi-Jun Yao; Bing-Feng Shi

doi:10.1002/anie.202208912

Single-Step Synthesis of Atropisomers with Vicinal C-C and C-N Diaxes by Cobalt-Catalyzed Atroposelective C-H Annulation

Angew Chem Int Ed Engl. 2022 Sep 26;61(39):e202208912. doi: 10.1002/anie.202208912. Epub 2022 Aug 23.

Authors

Bing-Jie Wang¹, Guo-Xiong Xu¹, Zong-Wei Huang², Xu Wu¹, Xin Hong¹, Qi-Jun Yao¹, Bing-Feng Shi^{1

3}

Affiliations

¹ Center of Chemistry for Frontier Technologies, Department of Chemistry, Zhejiang University, Hangzhou, 310027, China.
² Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.
³ Green Catalysis Center, College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China.

PMID: 35917381
DOI: 10.1002/anie.202208912

Abstract

The atroposelective synthesis of atropisomers with vicinal diaxes remains rare and challenging, due to the steric influence between the two axes and their unique topology. Herein, we disclose a single-step construction of atropisomers with vicinal C-C and C-N chiral diaxes by cyclopentadiene (Cp)-free cobalt-catalyzed intramolecular atroposelective C-H annulation, providing the desired diaxial atropisomers of unique structures with decent stereocontrols of both axes (up to >99 % ee and 70 : 1 dr). The optically pure products bearing fluorophores show circular polarized luminescence (CPL) properties, being candidate materials for potential CPL applications. Atropisomerization experiments and density function theory (DFT) calculations are conducted to study the rotational barriers and rotation pathways of the diaxes.

Keywords: Atroposelectivity; Cobalt; C−H Annulation; Salicyloxazoline; Vicinal Diaxis.

Abstract

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