Enantioselective synthesis of N-alkylindoles enabled by nickel-catalyzed C-C coupling
Lun Li1, Jiangtao Ren1,2, Jingjie Zhou1
1Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan Provincial Center for Research & Development of Natural Products, and State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan University, Kunming, China.
Abstract:
Enantioenriched N-alkylindole compounds, in which nitrogen is bound to a stereogenic sp3 carbon, are an important entity of target molecules in the fields of biological, medicinal, and organic chemistry. Despite considerable efforts aimed at inventing methods for stereoselective indole functionalization, straightforward access to a diverse range of chiral N-alkylindoles in an intermolecular catalytic fashion from readily available indole substrates remains an ongoing challenge. In sharp contrast to existing C-N bond-forming strategies, here, we describe a modular nickel-catalyzed C-C coupling protocol that couples a broad array of N-indolyl-substituted alkenes with aryl/alkenyl/alkynyl bromides to produce chiral N-alkylindole adducts in single regioisomeric form, in up to 91% yield and 97% ee. The process is amenable to proceed under mild conditions and exhibit broad scope and high functional group compatibility. Utility is highlighted through late-stage functionalization of natural products and drug molecules, preparation of chiral building blocks.
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