Radical C-Glycosylation Using Photoexcitable Unprotected Glycosyl Borate
Yusuke Miyamoto1, Sho Murakami1, Yuto Sumida2
1Institute for Chemical Research Kyoto University, 611-0011, Gokasho, Uji, Kyoto, Japan.
Abstract:
We have developed radical C-glycosylation using photoexcitable unprotected glycosyl borate. The direct excitation of glycosyl borate under visible light irradiation enabled the generation of anomeric radical without any photoredox catalysts. The in situ generated anomeric radical was applicable to the radical addition such as Giese-type addition and Minisci-type reaction to introduce alkyl and heteroaryl groups at the anomeric position. In addition, the radical-radical coupling between the glycosyl borate and acyl imidazolide provided unprotected acyl C-glycosides.
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