Zheng Yan-Xin, Liu Li-Gao, Hu Tian-Qi, Li Xiao, Xu Zhou, Hong Xin, Lu Xin, Zhou Bo, Ye Long-Wu
State Key Laboratory of Physical Chemistry of Solid Surfaces, Key Laboratory of Chemical Biology of Fujian Province, and College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China.
Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou, China.
Nat Commun. 2024 Oct 25;15(1):9227. doi: 10.1038/s41467-024-53605-7.
The asymmetric Büchner reaction and related arene cyclopropanations represent one type of the powerful methods for enantioselective dearomatization. However, examples of asymmetric Büchner reactions via a non-diazo approach are quite scarce, and the related arene cyclopropanation based on alkynes has not been reported. Herein, we disclose an asymmetric Büchner reaction and the related arene cyclopropanation by copper-catalyzed controllable cyclization of N-propargyl ynamides via vinyl cation intermediates, leading to chiral tricycle-fused cycloheptatrienes and benzonorcaradienes in high yields and enantioselectivities. Importantly, this protocol represents an asymmetric arene cyclopropanation reaction of alkynes and an asymmetric Büchner reaction based on vinyl cations.
不对称布赫纳反应及相关芳烃环丙烷化反应是对映选择性去芳构化的一类强大方法。然而，通过非重氮方法进行的不对称布赫纳反应实例相当稀少，且基于炔烃的相关芳烃环丙烷化反应尚未见报道。在此，我们报道了一种不对称布赫纳反应以及通过铜催化N-炔丙基烯酰胺经乙烯基阳离子中间体可控环化实现的相关芳烃环丙烷化反应，可高产率和对映选择性地得到手性三环稠合环庚三烯和苯并降蒈二烯。重要的是，该方法代表了一种炔烃的不对称芳烃环丙烷化反应以及基于乙烯基阳离子的不对称布赫纳反应。
