Ruthenium(II)-Catalyzed Tandem C–H Allylation and [3 + 2] Dipolar Cycloaddition to Construct Bridged Tetracycles
Junghyea Moon, Nayoung Ko, Seoeun Jang, Prithwish Ghosh, Hyung Sik Kim, Neeraj Kumar Mishra, In Su Kim
Abstract
The ruthenium(II)-catalyzed tandem C-H allylation and intramolecular dipolar cycloaddition between azomethine imines and 2-methylidenetrimethylene carbonate is described herein. The initially formed β-substituted allyl fragment could trigger the exotype [3 + 2] cycloaddition with the polar azomethine group, resulting in the formation of bridged tetracycles bearing a hydroxymethylene group at a bridgehead carbon center. A wide substrate scope and broad functional group compatibility were observed. The gram-scale synthesis and synthetic transformations demonstrate the synthetic utility of this process.
Topics & Concepts
ChemistryCycloadditionRutheniumTandemIntramolecular forceCatalysisStereochemistryFunctional groupCombinatorial chemistryOrganic chemistryMaterials scienceComposite materialPolymerCatalytic C–H Functionalization MethodsAsymmetric Hydrogenation and CatalysisCyclopropane Reaction Mechanisms