Synthesis of mono- and difluoroacetyltrialkylsilanes and the corresponding enol silyl ethers.
A variety of mono- and difluoroacetylsilanes and the corresponding silyl enol ethers were prepared from trifluoroethanol and chlorotrialkylsilanes in the presence of LDA through retro-Brook rearrangement. Sterically demanding silyl groups, especially those bound to oxygen, resulted in higher yields of difluoroacetylsilanes. The yields of difluoroacetylsilanes were also dramatically affected by the method of the termination of the reaction. Difluorohaloacetylsilanes were prepared from the corresponding difluoroethenyl silyl ethers with electrophilic halogenating reagents in good yields. A gamma-fluorinated beta-diketone 9a was prepared from monofluoroacetyltriisopropylsilane by nucleophilic acylation with methyl trifluoroacetate.
Higashiya
Seiichiro
S
Department of Chemistry, University at Albany, State University of New York, 1400 Washington Avenue, Albany, New York 12222, USA.
Chung
Woo Jin
WJ
Lim
Dong Sung
DS
Ngo
Silvana C
SC
Kelly
William H
WH
Toscano
Paul J
PJ
Welch
John T
JT