Diastereo- and enantioselective direct vinylogous Michael addition of γ-substituted butenolides to 2-enoylpyridines catalyzed by chiral bifunctional amine-squaramides.

نویسندگان

  • Zhen-Hua Wang
  • Zhi-Jun Wu
  • Xue-Qun Huang
  • Deng-Feng Yue
  • Yong You
  • Xiao-Ying Xu
  • Xiao-Mei Zhang
  • Wei-Cheng Yuan
چکیده

The diastereo- and enantioselective direct vinylogous Michael addition reaction of γ-substituted butenolides to 2-enoylpyridines has been achieved. A range of γ,γ-disubstituted butenolide derivatives, bearing two consecutive tri- and tetrasubstituted stereogenic centers, were readily obtained in good yields with excellent stereoselectivities (up to >99 : 1 dr and >99% ee).

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عنوان ژورنال:
  • Chemical communications

دوره 51 87  شماره 

صفحات  -

تاریخ انتشار 2015