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Synlett 2023; 34(18): 2175-2180
DOI: 10.1055/s-0041-1738448
DOI: 10.1055/s-0041-1738448
cluster
Modern Boron Chemistry: 60 Years of the Matteson Reaction
Photoredox-Catalyzed Radical–Radical Coupling of Potassium Trifluoroborates with Acyl Azoliums
We gratefully acknowledge support from the National Institute of General Medical Sciences (NIH) for support of this work (R35 GM136440). D.Y. and E.J.F. thank Northwestern for Undergraduate Research Grants. D.Y. thanks the Chemistry of Life Processes Institute at Northwestern for support in the form of the Lambert Fellowship.
Abstract
Potassium trifluoroborates have gained significant utility as coupling partners in organic synthesis, particularly in the Suzuki–Miyaura coupling reaction. Recently, they have also been used as radical precursors under oxidative conditions to generate carbon-centered radicals. These versatile reagents have found new applications in photoredox catalysis, including radical substitution, conjugate-addition reactions, and transition-metal dual catalysis. In addition, this photomediated redox-neutral process has enabled radical–radical coupling with persistent radicals in the absence of a metal, and this process remains to be fully explored. In this study, we report the radical–radical coupling of potassium benzylic trifluoroborate salts with isolated acyl azolium triflates, which are persistent-radical precursors. The reaction is catalyzed by an organic photocatalyst and forms isolable tertiary alcohol species. These products can be transformed into a range of substituted ketone products by simple treatment with a mild base.
Key words
potassium trifluoroborate - photoredox catalysis - organophotocatalysis - acyl azolium compounds - radical–radical coupling - ketonesSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0041-1738448.
- Supporting Information
Publication History
Received: 04 May 2023
Accepted after revision: 14 June 2023
Article published online:
16 August 2023
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