Iridium‐Catalyzed Enantioselective Intramolecular Hydroarylation of Allenes: Formal Synthesis of (+)‐Rhazinilam

We report a versatile, highly enantioselective intramolecular hydroarylation of allenyl-tethered pyrroles and indoles. The reaction, promoted by an iridium(I)/bisphosphine chiral catalyst, provides a direct access heteropolycyclic systems bearing either tertiary or quaternary carbon stereocenters and a synthetically appealing alkenyl pendant. The method allows a highly efficient assembly of five-, six- and even seven-membered fused indole and pyrrole products, providing enantiomeric excesses of up to 99%. DFT computational studies align nicely with the experimental results and allow to rationalize the key factors that control both regio- and stereoselectivity of the process. Finally, the synthetic potential of the method was exemplified with a very short, highly enantioselective formal synthesis of (+)-Rhazinilam.