A Pragmatic Radical Strategy for Dearomative Hydroalkylation of Unactivated Indoles
Chao Hu1, Renzhe Li1, Rohan R Merchant2
1Department of Biochemistry, The University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, Texas 75390, United States.
Abstract:
Dearomative functionalization offers a direct approach for transforming planar aromatics into C(sp3)-rich frameworks with potentially improved drug-like properties. Herein, we report a metal-free and operationally simple method with broad functional group tolerance for the dearomative hydroalkylation of indoles using alkyl boronates. This strategy advances the radical-based dearomatization strategy to previously unreactive indole substrates, enabling access to a variety range of three-dimensional indolines. Notably, it highlights the use of transient indolenium ions in radical-mediated C-C bond formation, establishing a new platform for rapidly diversifying indole-derived scaffolds.
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