Phosphine-Catalyzed Cascade [3 + 2] Cyclization−Allylic Alkylation, [2 + 2 + 1] Annulation, and [3 + 2] Cyclization Reactions between Allylic Carbonates and Enones
datasetposted on 18.02.2011, 00:00 by Rong Zhou, Jianfang Wang, Haibin Song, Zhengjie He
The phosphine-catalyzed annulations between Morita−Baylis−Hillman adduct carbonates and enones are reported. Under the catalysis of PBu3 (20 mol %), cascade [3 + 2] cyclization−allylic alkylation, [2 + 2 + 1] annulation, and [3 + 2] cyclization reactions chemoselectively occur depending on the substituent variation of both the carbonate and enone. These reactions provide efficient syntheses of highly functionalized cyclopentenes and cyclopentanes.