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Updated: Jan 11, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Rhodium-Catalyzed Asymmetric Remote C(sp3)-H Borylation of Aldehyde-Derived Silyl Enol Ethers
Yisen Yao1, Jie Li1, Jintao Sun1
1State Key Laboratory of Chemo and Biosensing, Advanced Catalytic Engineering Research Center of the Ministry of Education, College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan 410082, P. R. China.
Abstract:
The asymmetric remote C(sp3)-H borylation of alkenes has become an effective means of remote functionalization. However, the application of silyl enol ethers in this transformation remains underexplored. Herein, we report a Rh-catalyzed asymmetric remote C(sp3)-H borylation of silyl enol ethers, using (R,R,R,R)-OMe-BIBOP as the chiral ligand, delivering enantioenriched borylethers (up to 96:4 er) in good yields (up to 96%). This protocol shows a diverse range of substrate scopes, and the practicality of this method was showcased through scalable reactions and broad product transformations. In vitro antibacterial studies for diols have demonstrated their potential as pesticide molecules. Preliminary mechanistic studies suggest that the geometric configuration of the silyl enol ethers has no effect on the enantioselectivity of the products.
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