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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Tandem [2+4] annulation/aromatization reaction of yne-enones with o-sulfonamidobenzaldehydes
Zhiyang Cui1, Honghao Sun1, Jingrong Jin1
1Department of Applied Chemistry, China Agricultural University, Beijing 100193, China. hchguo@cau.edu.cn.
Abstract:
Yne-enones are valuable platform molecules that undergo diverse transformations under both metal-catalyzed and metal-free conditions. However, their participation in phosphine-catalyzed annulation reactions has remained relatively unexplored. Herein, a phosphine-catalyzed tandem [2+4] annulation/detosylative aromatization of yne-enones with o-sulfonamidobenzaldehydes is reported, affording polyfunctionalized quinolines in moderate to high yields with a broad substrate scope. A plausible reaction mechanism is proposed, highlighting the potential of yne-enones to serve as versatile synthons for the development of new annulation strategies under phosphine catalysis.
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