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An aza-Robinson Annulation Strategy for the Synthesis of Fused Bicyclic Amides: Synthesis of (±)-Coniceine and Quinolizidine.

ABSTRACT: An aza-Robinson annulation strategy is described using a NaOEt-catalyzed conjugate addition of cyclic imides onto vinyl ketones, followed by a TfOH-mediated intramolecular aldol condensation to afford densely functionalized fused bicyclic amides. The potential use of these amides in the synthesis of alkaloids is demonstrated by the sequential conversion of appropriate precursors to (±)-coniceine and quinolizidine in two additional steps, thus allowing their preparation in overall 40 and 44% yields, respectively.

SUBMITTER: Garay-Talero A

PROVIDER: S-EPMC10630962 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature

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An <i>aza</i>-Robinson Annulation Strategy for the Synthesis of Fused Bicyclic Amides: Synthesis of (±)-Coniceine and Quinolizidine.

Garay-Talero Alexander A Goulart Tales A C TAC Gallo Rafael D C RDC Pinheiro Roberto do C RDC Hoyos-Orozco Catalina C Jurberg Igor D ID Gamba-Sánchez Diego D

Organic letters 20231025 43

An <i>aza</i>-Robinson annulation strategy is described using a NaOEt-catalyzed conjugate addition of cyclic imides onto vinyl ketones, followed by a TfOH-mediated intramolecular aldol condensation to afford densely functionalized fused bicyclic amides. The potential use of these amides in the synthesis of alkaloids is demonstrated by the sequential conversion of appropriate precursors to (±)-coniceine and quinolizidine in two additional steps, thus allowing their preparation in overall 40 and 4 ...[more]

PMID: 37877616

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