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Updated: Sep 20, 2025
Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Iridium-Catalyzed Enantioselective Intramolecular Hydroarylation of Allenes: Formal Synthesis of (+)-Rhazinilam
Andrés Arribas1, Alejandro Rey1, Martín Calvelo1
1Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS) and Departamento de Química Orgánica, Universidade de Santiago de Compostela, Santiago de Compostela, 15782, Spain.
Abstract:
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.
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