Base-Mediated Claisen Rearrangement of CF3-Containing Bisallyl Ethers

We have previously clarified that the strongly electron-withdrawing CF₃ group nicely affected the base-mediated proton shift of CF₃-containing propargylic or allylic alcohols to afford the corresponding α,β-unsaturated or saturated ketones, respectively, which was applied this time to the Claisen rearrangement after O-allylation of the allylic alcohols with a CF₃ group, followed by isomerization to the corresponding allyl vinyl ethers via the proton shift, enabling the desired rearrangement in a tandem fashion, or in a stepwise manner, the latter of which was proved to have attained an excellent diastereoselectivity with the aid of a palladium catalyst.