Mild Rhodium(III)-Catalyzed Cyclization of Amides with α,β-Unsaturated Aldehydes and Ketones to Azepinones: Application to the Synthesis of the Homoprotoberberine Framework


  • We thank Karl Collins for helpful discussions. This work was supported by the Alexander von Humboldt Foundation (Z.S.) and the Deutsche Forschungsgemeinschaft (IRTG Münster-Nagoya). Generous financial support by the European Research Council under the European Community’s Seventh Framework Program (FP7 2007-2013)/ERC Grant agreement no. 25936 is gratefully acknowledged.


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Seven! The title reaction can be described as an intermolecular annulation involving tandem C[BOND]H activation, cyclization to give the seven-membered ring, and condensation steps. Biologically interesting azepinone derivatives can be prepared in this way. The synthetic potential of this method was demonstrated by the construction of the homoprotoberberine ring system.