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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Synthesis of Stilbene Derivatives via Phosphine-Catalyzed Cascade [2+4] Annulation/Decarboxylative Aromatization of
Mingxia Huang1, Yi Tang1, Jingrong Jin1
1Department of Chemistry, China Agricultural University, Beijing 100193, P. R. China.
Abstract:
Despite significant advances in phosphine catalysis for synthesizing diverse cyclic frameworks, phosphine-catalyzed benzannulation reactions remain largely underexplored. In this work, we report a phosphine-catalyzed cascade [2+4] annulation/decarboxylative aromatization reaction between yne-enones and α-pyrones, which provides access to a wide range of functionalized stilbene derivatives in moderate to high yields (up to 98%). The reaction exhibits scalability and allows facile derivatization of products, highlighting its practical utility. A proposed mechanism outlines a stepwise annulation pathway and further underscores the unique reactivity of yne-enones in phosphine-catalyzed transformations.
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