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Organocatalytic Asymmetric Peroxidation of γ,δ-Unsaturated β-Keto Esters-A Novel Route to Chiral Cycloperoxides.

ABSTRACT: A methodology for the asymmetric peroxidation of γ,δ-unsaturated β-keto esters is presented. Using a cinchona-derived organocatalyst, the target δ-peroxy-β-keto esters were obtained in high enantiomeric ratios of up to 95:5. Additionally, these δ-peroxy esters can be readily reduced to chiral δ-hydroxy-β-keto esters without impacting the β-keto ester functionality. Importantly, this chemistry opens up a concise route to chiral 1,2-dioxolanes, a common motif in many bioactive natural products, via a novel P₂O₅-mediated cyclisation of the corresponding δ-peroxy-β-hydroxy esters.

SUBMITTER: Hennessy MC

PROVIDER: S-EPMC10254861 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Organocatalytic Asymmetric Peroxidation of γ,δ-Unsaturated β-Keto Esters-A Novel Route to Chiral Cycloperoxides.

Hennessy Mary C MC Gandhi Hirenkumar H O'Sullivan Timothy P TP

Molecules (Basel, Switzerland) 20230524 11

A methodology for the asymmetric peroxidation of γ,δ-unsaturated β-keto esters is presented. Using a cinchona-derived organocatalyst, the target δ-peroxy-β-keto esters were obtained in high enantiomeric ratios of up to 95:5. Additionally, these δ-peroxy esters can be readily reduced to chiral δ-hydroxy-β-keto esters without impacting the β-keto ester functionality. Importantly, this chemistry opens up a concise route to chiral 1,2-dioxolanes, a common motif in many bioactive natural products, vi ...[more]

PMID: 37298799

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