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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, and diazocarbonyl carbene insertion. Various spiroindolines and spirodihydrobenzofurans containing two quartenary carbon stereocenters were readily obtained in good to excellent yields. A preliminary study of asymmetric spirocyclization using chiral monophosphoramidite as a ligand was also conducted, enabling access to highly valuable chiral spiroindolines with up to 80% ee. [ABSTRACT FROM AUTHOR]