TEMPO as a Hydrogen Atom Transfer Catalyst for Aerobic Dehydrogenation of Activated Alkanes to Alkenes
Tasuku Ito1, Falk William Seidel1, Xiongjie Jin1
1Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
Abstract:
2,2,6,6-Tetramethylpiperidine-N-oxyl (TEMPO) has been extensively utilized as a radical scavenger or an oxidation catalyst. In contrast, TEMPO as a hydrogen atom transfer (HAT) catalyst has rarely been studied. Here, we report that TEMPO, as the HAT catalyst, homolytically cleaves benzylic or allylic C-H bonds to give the corresponding alkyl radicals. Benefiting from the dual roles played by TEMPO as the HAT catalyst and the radical scavenger, the highly challenging aerobic dehydrogenation of activated alkanes to alkenes is successfully developed.
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