PPh3-Catalyzed (3 + 3) Annulations of 5-Acetoxypenta-2,3-dienoate with 1C,3O-Bisnucleophiles: Facile Entry to Stable Monocyclic 2H-Pyrans
Jian Hu, Wei Dong, Xin-Yan Wu and Xiaofeng Tong*
*Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road No. 130, Shanghai, 200237, P. R. China, Email: tongxfecust.edu.cn
J. Hu, W. Dong, X.-Y. Wu, X. Tong, Org. Lett., 2012, 14, 5530-5533.
DOI: 10.1021/ol302634p (free Supporting Information)
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Phosphine-catalyzed (3 + 3) annulations between allenoates and 1C,3O-bisnucleophiles provide a facile entry to stable 2H-pyrans which are greatly challenging targets in organic synthesis. (3 + 2) Annulations can be achieved with the assistance of base to yield furans.
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