Li Tong, Zhang Yanbo, Du Cong, Yang Dandan, Song Mao-Ping, Niu Jun-Long
College of Chemistry, Pingyuan Laboratory, Zhengzhou University, Zhengzhou, China.
School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng, China.
Nat Commun. 2024 Sep 3;15(1):7673. doi: 10.1038/s41467-024-52133-8.
The simultaneous construction of multiple stereogenic elements in a single step is highly appealing and desirable in the field of asymmetric synthesis. Furthermore, the catalytic enantioselective synthesis of inherently chiral calix[n]arenes with high enantiopurity has long been a challenging endeavor. Herein, we report an enantioselective cobalt-catalyzed C-H activation/annulation for the efficient construction of inherently chiral calix[4]arenes bearing multiple C-N axially chiral element. By employing the benzamide tethered calix[4]arene as the substrate, the C-H annulation with alkynes can be successfully accomplished, leading to the generation of multiple stereogenic elements. A wide range of calix[4]arenes and alkynes are found to be well compatible, and exhibit good yields, high enantioselectivity and excellent diastereoselectivity. Notably, the gram-scale reaction, catalytic application, synthetic transformations, and chiral recognition further showcase the potential applications of this protocol.
在不对称合成领域，一步同时构建多个手性中心极具吸引力且十分必要。此外，催化对映选择性合成具有高对映纯度的固有手性杯[n]芳烃长期以来一直是一项具有挑战性的工作。在此，我们报道了一种对映选择性钴催化的C-H活化/环化反应，用于高效构建含有多个C-N轴手性元素的固有手性杯[4]芳烃。通过使用苯甲酰胺连接的杯[4]芳烃作为底物，可以成功实现与炔烃的C-H环化反应，从而产生多个手性中心。发现多种杯[4]芳烃和炔烃具有良好的兼容性，并表现出良好的产率、高对映选择性和优异的非对映选择性。值得注意的是，克级反应、催化应用、合成转化和手性识别进一步展示了该方法的潜在应用。
