Palladium-Catalyzed [3 + 2] Annulation of Aromatic Amides with Maleimides through Dual C–H Activation
Gouranga Naskar, Masilamani Jeganmohan
Abstract
A palladium-catalyzed [3 + 2] annulation of substituted aromatic amides with maleimides providing tricyclic heterocyclic molecules in good to moderate yields through weak carbonyl chelation is reported. The reaction proceeds via a dual C–H bond activation where the first C–H activation takes place selectively at the benzylic position followed by a second C–H bond activation at the meta position to afford a five-membered cyclic ring. An external ligand Ac-Gly-OH has been used to succeed in this protocol. A plausible reaction mechanism has been proposed for the [3 + 2] annulation reaction.
Topics & Concepts
AnnulationChemistryPalladiumCatalysisRing (chemistry)MoleculeLigand (biochemistry)Medicinal chemistryStereochemistryCombinatorial chemistryOrganic chemistryReceptorBiochemistryCatalytic C–H Functionalization MethodsCatalytic Cross-Coupling ReactionsSynthesis and Catalytic Reactions