DOI: 10.1021/acs.orglett.6c04056 ISSN: 1523-7060
Asymmetric Synthesis of Functionalized gem -Difluoromethylenecyclopropanes via Rh(III)-Catalyzed Redox-Neutral C–H Coupling
Fu-Xiaomin Liu, Weijie Chen, Ying Cai, Haohui Zhu, Dan Qiu, Lincan He, Silin Zhang, Shengdong Wang, Zhongyi Zeng, Wei Yi, Zhi ZhouAbstract
Fluorinated cyclopropane skeletons possess significant synthetic utility and medicinal potential. Herein, the Rh(III)-catalyzed redox-neutral C–H coupling of indole derivatives with gem-difluorocyclopropenol carboxylates was realized in both a racemic and asymmetric manner, giving access to the divergent synthesis of functionalized gem-difluoromethylenecyclopropanes with broad substrate compatibility, good enantioselectivity, and profound synthetic application. This protocol occurred via a tandem C–H activation/alkene insertion/β-O elimination process, thereby precluding the competitive fluoride elimination and ring scission of the strained cyclopropane.