Mesyloxy-group migration as the stereoselective preparation method of various functionalized olefins and its reaction mechanism.
[structure: see text]. It was demonstrated that mesylation of appropriate gamma,gamma-difluorinated allylic alcohols under usual conditions furnished the corresponding alpha,alpha-difluorinated allylic mesylates, possibly by way of 1,3-mesyloxy-group migration after formation of the expected "normal" intermediates, gamma,gamma-difluorinated allylic mesylates. This rearrangement was conveniently applied to the construction of trisubstituted allylic alcohols, alpha,beta-unsaturated esters, amides, or ketones in good to excellent chemical yields with exclusive E selectivities.
Department of Bioengineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan. tyamazak@bio.titech.ac.jp
T
T
Yamazaki
S
S
Hiraoka
J
J
Sakamoto
T
T
Kitazume