Chiral phosphoproline-catalyzed asymmetric Michael addition of ketones to nitroolefins: an experimental and theoretical study.

نویسندگان

  • Zhiping Zeng
  • Ping Luo
  • Yao Jiang
  • Yan Liu
  • Guo Tang
  • Pengxiang Xu
  • Yufen Zhao
  • G Michael Blackburn
چکیده

A novel pyrrolidine-based chiral phosphoproline is an effective bifunctional organocatalyst for the asymmetric Michael addition of ketones to nitroolefins giving high levels of diastereo- and enantio-selectivities (up to > 99 : 1 dr and 96% ee). anti-SR Transition state has the lowest barrier which controls the stereoselectivity, in agreement with experimental results.

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عنوان ژورنال:
  • Organic & biomolecular chemistry

دوره 9 20  شماره 

صفحات  -

تاریخ انتشار 2011