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Updated: Jun 16, 2025
A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
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Borane-Catalyzed Enantioselective α-Alkylation of Unactivated 2-Alkylbenzoxazoles with Electron-Deficient Olefins
Chong-Ren Ai1, Lu Liu1, Xiao-Chen Wang1
1State Key Laboratory and Institute of Elemento-Organic Chemistry, Haihe Laboratory of Sustainable Chemical Transformations, Frontiers Science Center for New Organic Matter, College of Chemistry, Nankai University, Tianjin 300071, China.
Abstract:
Chiral borane-catalyzed reactions have recently emerged as a powerful tool for the enantioselective production of chiral scaffolds. In this study, we demonstrated for the first time that a chiral bisborane catalyst can be used for the α-functionalization of 2-alkylazaarenes; specifically, we accomplished unprecedented highly enantioselective α-alkylation of unactivated 2-alkylbenzoxazoles with electron-deficient olefins. The strong Lewis acidity and the steric bulk of the bisborane catalyst were essential to the observed reactivity and selectivity.
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