Chemoselective Oxidation by Electronically Tuned Nitroxyl Radical Catalysts†
Shohei Hamada
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Search for more papers by this authorDr. Takumi Furuta
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Search for more papers by this authorYoshiyuki Wada
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Search for more papers by this authorCorresponding Author
Prof. Dr. Takeo Kawabata
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)Search for more papers by this authorShohei Hamada
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Search for more papers by this authorDr. Takumi Furuta
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Search for more papers by this authorYoshiyuki Wada
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Search for more papers by this authorCorresponding Author
Prof. Dr. Takeo Kawabata
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)
Institute for Chemical Research, Kyoto University, Uji, Kyoto 611-0011(Japan)Search for more papers by this authorWe are grateful to Prof. Norihiro Tokitoh and Dr. Takahiro Sasamori for generous assistance to the measurement of cyclic voltammetry. This work was supported by a Grant-in-Aid for Scientific Research on Innovative Areas “Advanced Molecular Transformation by Organocatalysts” from The Ministry of Education, Culture, Sports, Science and Technology (Japan), and by Grant-in-Aid for JSPS Fellows to S.H.
Graphical Abstract
Electronic tuning: Nitroxyl radical 1 is shown to be an efficient catalyst for the oxidation of secondary alcohols, and promotes oxidation through an oxoammonium species which is highly reactive because of the adjacent electron-withdrawing ester groups. Chemoselective oxidation of benzylic alcohols in the presence of aliphatic alcohols is observed and is proposed to proceed by a rate-determining hydride transfer.
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