Mesyloxy-Group Migration as the Stereoselective Preparation Method of Various Functionalized Olefins and Its Reaction Mechanism

Abstract

[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.