<i>cis</i>-Selective, Enantiospecific Addition of Donor–Acceptor Cyclopropanes to Activated Alkenes: An Iodination/Michael-Cyclization Cascade
Nils L. Ahlburg, Peter G. Jones, Daniel B. Werz
Abstract
-diastereoselective intermolecular and intramolecular cycloaddition of donor-acceptor cyclopropanes to electron-poor alkenes with cyclic acceptor groups to afford highly substituted spirocyclopentanes in good to excellent yields. The reaction can be applied to biologically interesting scaffolds, including barbiturates and isoxazolones. Mechanistic investigations were undertaken to explain the unusual diastereoselectivity and enantiospecificity; these suggest an iodination/Michael-cyclization cascade.
Topics & Concepts
ChemistryIntramolecular forceHalogenationMichael reactionCascadeIntermolecular forceAcceptorCycloadditionStereochemistryCombinatorial chemistryOrganic chemistryMoleculeCatalysisPhysicsChromatographyCondensed matter physicsCyclopropane Reaction MechanismsCatalytic Alkyne ReactionsAsymmetric Synthesis and Catalysis