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Base-Mediated Claisen Rearrangement of CF3-Containing Bisallyl Ethers.

ABSTRACT: 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.

SUBMITTER: Hamada Y

PROVIDER: S-EPMC8304132 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Base-Mediated Claisen Rearrangement of CF3-Containing Bisallyl Ethers.

Hamada Yoko Y Matsunaga Rio R Kawasaki-Takasuka Tomoko T Yamazaki Takashi T

Molecules (Basel, Switzerland) 20210719 14

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, ...[more]

PMID: 34299639

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