Palladium-Catalyzed Asymmetric (2+3) Annulation of <i>p</i>-Quinone Methides with Trimethylenemethanes: Enantioselective Synthesis of Functionalized Chiral Spirocyclopentyl <i>p</i>-Dienones
Zhi-Long Jia, Xian‐Tao An, Yu‐Hua Deng, Huibin Wang, Kang‐Ji Gan, Jing Zhang, Xian‐He Zhao, Chun‐An Fan
Abstract
A novel asymmetric catalytic (2+3) annulation of p-quinone methides with CN-substituted trimethylenemethane is described under palladium catalysis, providing an alternative approach for the enantioselective construction of highly functionalized chiral spirocyclopentyl p-dienones. Driven by the significant improvement in the reactivity and enantioselectivity, a novel type of non-C2-symmetric phosphoramidite ligand from the chirality-matched combination of (S)-BINOL and sterically demanding amine derived from l-hydroxyproline is evolved and explored for the protocol presented here.
Topics & Concepts
Enantioselective synthesisChemistryAnnulationPhosphoramiditePalladiumCatalysisTrimethylenemethaneSteric effectsCombinatorial chemistryAmine gas treatingLigand (biochemistry)Reactivity (psychology)Organic chemistryStereochemistryCycloadditionReceptorBiochemistryOligonucleotideDNAMedicinePathologyAlternative medicineSynthesis of Indole DerivativesAxial and Atropisomeric Chirality SynthesisSulfur-Based Synthesis Techniques