Facile synthesis of 1,1-difluoroallenes via the difluorovinylidenation of aldehydes and ketones.
2-Bromo-3,3-difluoroallylic acetates were readily prepared by the reaction of carbonyl compounds with 1-bromo-2,2-difluorovinyllithium, generated from 1,1-dibromo-2,2-difluoroethylene, followed by acetylation. On treatment with butyllithium, the bromoacetates underwent selective 1,2-elimination of lithium acetate to afford mono- and disubstituted 1,1-difluoroallenes in high yields.
Yokota
Misaki
M
Department of Chemistry, Graduate School of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan.
Fuchibe
Kohei
K
Ueda
Mikiko
M
Mayumi
Yuka
Y
Ichikawa
Junji
J