Synthesis of α-Trifluoromethylated Ketones from Vinyl Triflates in the Absence of External Trifluoromethyl Sources
Corresponding Author
Dr. Takuji Kawamoto
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611 Japan
Search for more papers by this authorRio Sasaki
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611 Japan
Search for more papers by this authorCorresponding Author
Prof. Dr. Akio Kamimura
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611 Japan
Search for more papers by this authorCorresponding Author
Dr. Takuji Kawamoto
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611 Japan
Search for more papers by this authorRio Sasaki
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611 Japan
Search for more papers by this authorCorresponding Author
Prof. Dr. Akio Kamimura
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611 Japan
Search for more papers by this authorAbstract
A novel method for the conversion of vinyl triflates into α-trifluoromethylated ketones in the absence of external trifluoromethyl sources is described. This process accomplishes an efficient migration of the trifluoromethyl group of the triflate to the α-position in the ketone through a radical process. The reaction proceeds by the addition of a trifluoromethyl radical to the vinyl triflate and subsequent fragmentation of the trifluoromethane sulfonyl radical. Based on this reaction, a one-pot two-step procedure for the trifluoromethylation of ketones was developed. The method presented herein also allows the transfer of perfluoroalkyl groups from vinyl perfluoroalkanesulfonates, which are readily accessible from alkynes and perfluoroalkanesulfonic acids.
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