Synthesis of α-Trifluoromethylated Ketones from Vinyl Triflates in the Absence of External Trifluoromethyl Sources.
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.
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611, Japan.
Takuji
0000-0002-1845-4700
T
Kawamoto
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611, Japan.
Rio
R
Sasaki
Department of Applied Chemistry, Yamaguchi University, Ube, Yamaguchi, 755-8611, Japan.
Akio
0000-0002-3060-4265
A
Kamimura
boranes; radicals; reaction mechanisms; synthetic methods; trifluoromethylation