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Asymmetric Induction via a Helically Chiral Anion: Enantioselective Pentacarboxycyclopentadiene Bronsted Acid-Catalyzed Inverse-Electron-Demand Diels-Alder Cycloaddition of Oxocarbenium Ions.

ABSTRACT: An enantioselective catalytic inverse-electron-demand Diels-Alder reaction of salicylaldehyde acetal-derived oxocarbenium ions and vinyl ethers to generate 2,4-dioxychromanes is described. Chiral pentacarboxycyclopentadiene (PCCP) acids are found to be effective for a variety of substrates. Computational and X-ray crystallographic analyses support the unique hypothesis that an anion with point-chirality-induced helical chirality dictates the absolute sense of stereochemistry in this reaction.

SUBMITTER: Gheewala CD

PROVIDER: S-EPMC5859540 | biostudies-literature | 2018 Mar

REPOSITORIES: biostudies-literature

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Asymmetric Induction via a Helically Chiral Anion: Enantioselective Pentacarboxycyclopentadiene Brønsted Acid-Catalyzed Inverse-Electron-Demand Diels-Alder Cycloaddition of Oxocarbenium Ions.

Gheewala Chirag D CD Hirschi Jennifer S JS Lee Wai-Hang WH Paley Daniel W DW Vetticatt Mathew J MJ Lambert Tristan H TH

Journal of the American Chemical Society 20180306 10

An enantioselective catalytic inverse-electron-demand Diels-Alder reaction of salicylaldehyde acetal-derived oxocarbenium ions and vinyl ethers to generate 2,4-dioxychromanes is described. Chiral pentacarboxycyclopentadiene (PCCP) acids are found to be effective for a variety of substrates. Computational and X-ray crystallographic analyses support the unique hypothesis that an anion with point-chirality-induced helical chirality dictates the absolute sense of stereochemistry in this reaction. ...[more]

PMID: 29485273

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