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Electrochemical Bromination of Glycals.

ABSTRACT: Herein, the convenient one-step electrochemical bromination of glycals using Bu₄NBr as the brominating source under metal-catalyst-free and oxidant-free reaction conditions was described. A series of 2-bromoglycals bearing different electron-withdrawing or electron-donating protective groups were successfully synthesized in moderate to excellent yields. The coupling of tri-O-benzyl-2-bromogalactal with phenylacetylene, potassium phenyltrifluoroborate, or a 6-OH acceptor was achieved to afford 2C-branched carbohydrates and disaccharides via Sonogashira coupling, Suzuki coupling, and Ferrier rearrangement reactions with high efficiency. The radical trapping and cyclic voltammetry experiments indicated that bromine radicals may be involved in the reaction process.

SUBMITTER: Luo ZX

PROVIDER: S-EPMC8732377 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Electrochemical Bromination of Glycals.

Luo Zhao-Xiang ZX Liu Miao M Li Tian T Xiong De-Cai DC Ye Xin-Shan XS

Frontiers in chemistry 20211223

Herein, the convenient one-step electrochemical bromination of glycals using Bu<sub>4</sub>NBr as the brominating source under metal-catalyst-free and oxidant-free reaction conditions was described. A series of 2-bromoglycals bearing different electron-withdrawing or electron-donating protective groups were successfully synthesized in moderate to excellent yields. The coupling of tri-<i>O</i>-benzyl-2-bromogalactal with phenylacetylene, potassium phenyltrifluoroborate, or a 6-OH acceptor was ach ...[more]

PMID: 35004613

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