Boryl Radical-Promoted Dehydroxylative Alkylation of 3-Hydroxyoxindole Derivatives
Tesfaye Tebeka Simur1, Tian-Yu Peng1, Yi-Feng Wang1
1Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
Abstract:
A boryl radical-promoted dehydroxylative alkylation of 3-hydroxy-oxindole derivatives is achieved. The reaction starts from addition of 4-dimethylaminopyridine (DMAP)-boryl radical to the amide carbonyl oxygen atom, which induces a spin-center shift process to promote the C-O bond cleavage. The elimination of a hydroxide anion from a free hydroxy group is also accomplished. Capture of the generated carbon radical with alkenes furnishes a variety of C-3 alkylated oxindoles. This method features a simple operation and broad substrate scope.
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