Access to Spiroindolines and Spirodihydrobenzofurans via Pd-Catalyzed Domino Heck Spiroyclization through C–H Activation and Carbene Insertion

摘要: A new palladium-catalyzed domino approach for the synthesis of attractive spirocyclic indolines and dihydrobenzofurans was developed. The reaction proceeds through a sequential intramolecular Heck spirocyclization, remote C–H activation, diazocarbonyl carbene insertion. Various spiroindolines spirodihydrobenzofurans containing two quartenary carbon stereocenters were readily obtained in good to excellent yields. preliminary study asymmetric spirocyclization using chiral monophosphoramidite as ligand also conducted, enabling access highly valuable with up 80% ee.