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Enantioselective Catalysis of an Anionic Oxy-Cope Rearrangement Enabled by Synergistic Ion Binding.

ABSTRACT: Charge-accelerated rearrangements present interesting challenges to enantioselective catalysis, due in large part to the competing requirements for maximizing reactivity (ion-pair separation) and stereochemical communication. Herein, we describe application of a synergistic ion-binding strategy to catalyze the anionic oxy-Cope rearrangement of a symmetric bis-styrenyl allyl alcohol in up to 75:25 e.r. Structure-reactivity-selectivity relationship studies, including linear free-energy-relationship analyses, with bifunctional urea catalysts indicate that H-bonding and cation-binding interactions act cooperatively to promote the chemo- and enantioselective [3,3]-rearrangement. Implications for catalyst designs applicable to other transformations involving oxyanionic intermediates are discussed.

SUBMITTER: Kennedy CR

PROVIDER: S-EPMC7592710 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Enantioselective Catalysis of an Anionic Oxy-Cope Rearrangement Enabled by Synergistic Ion Binding.

Kennedy C Rose CR Choi Bo Young BY Reeves Mary-Grace R MR Jacobsen Eric N EN

Israel journal of chemistry 20200306 3-4

Charge-accelerated rearrangements present interesting challenges to enantioselective catalysis, due in large part to the competing requirements for maximizing reactivity (ion-pair separation) and stereochemical communication. Herein, we describe application of a synergistic ion-binding strategy to catalyze the anionic oxy-Cope rearrangement of a symmetric <i>bis</i>-styrenyl allyl alcohol in up to 75:25 e.r. Structure-reactivity-selectivity relationship studies, including linear free-energy-rela ...[more]

PMID: 33132416

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