Pd-Catalyzed Dual C–H Activation/Cyclization: Convergent and Divergent Synthesis of 1-Azahelicenes
Yi-Xin Xu, Yu-Qing Liang, Wei-Ming Liu, Hui-Kang Fang, Hong-Kun Li, Shun-Jun Ji(纪顺俊)*,Zhong-Jian Cai(蔡忠建)*
Key Laboratory of Organic Synthesis of Jiangsu Province, College of Chemistry, Chemical Engineering and Materials Science & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University,Suzhou 215123, P. R. China
Org. Lett. 2024, 26, 42, 9005–9010
Abstract: Herein, we report a convergent synthesis of 1-azahelicenes using easily available quinoline derivatives and cyclic diaryliodonium salts as starting materials. This reaction undergoes a palladium-catalyzed dual C–H activation/cyclization process to give facile access to a wide range of 1-aza[5]helicenes and 1-aza[6]helicenes with abundant functional groups (including F, Cl, Br, I, CF3, SeR, SR, and heteroaryl) in moderate to excellent yields, thereby providing new opportunities to fine-tune the properties of the helicene backbone. In addition, the obtained products could be further transformed into helicene-based Lewis base catalysts and redox switch materials easily. Notably, one selected 1-azahelicene shined bright yellow light by aggregation. These features enlarge the chemical space of 1-azahelicenes and inspire further utilization in other areas of research.
Article information: //doi.org/10.1021/acs.orglett.4c03136
