Iridium-Catalyzed Intramolecular Enantioselective C-H Alkylation at the C-2 Position of N-Alkenylindoles

Intramolecular enantioselective alkylation of N-alkenylindoles proceeded via C-H bond cleavage at the C-2 position in the presence of a cationic iridium catalyst with a diphosphine ligand. Aroyl groups at the C-3 position of the indoles operated as effective directing groups, and chiral 1-substituted-2,3-dihydro-1H-pyrrolo[1,2-a] indoles were obtained in high yield with excellent ee.