Intermolecular [5+2] Annulation between 1‐Indanones and Internal Alkynes by Rhodium‐Catalyzed C–C Activation
Rui Zhang, Ying Xia, Guangbin Dong
Abstract
Herein, we report a [5+2] cycloaddition between readily accessible 1-indanones and internal alkynes through Rh-catalyzed activation of less strained C-C bonds. The reaction is enabled by a strongly σ-donating NHC ligand and a carefully modified temporary directing group. A wide range of functional groups is tolerated, and the method provides straightforward access to diverse benzocycloheptenones that are hard to access otherwise. DFT studies of the reaction mechanism imply the migration insertion as the turnover-limiting step and suggest beneficial π-π interactions in the transition states.
Topics & Concepts
AnnulationIntermolecular forceRhodiumCycloadditionChemistryCatalysisLimitingLigand (biochemistry)Transition stateStereochemistryReaction mechanismMedicinal chemistryCombinatorial chemistryMoleculeOrganic chemistryReceptorEngineeringMechanical engineeringBiochemistryCatalytic C–H Functionalization MethodsCatalytic Alkyne ReactionsCyclopropane Reaction Mechanisms