Chiral N-phosphonyl imine chemistry: an efficient asymmetric synthesis of chiral N-phosphonyl propargylamines.

نویسندگان

  • Parminder Kaur
  • Gaurav Shakya
  • Hao Sun
  • Yi Pan
  • Guigen Li
چکیده

A variety of substituted chiral propargylamines have been synthesized by reacting chiral N-phosphonylimines with lithium aryl/alkyl acetylides. Seventeen examples were studied to give excellent yields (>90%) and diastereoselectivities (96 : 4 to 99 : 1). It was found that the types of bases for generating acetylides and solvents are crucial for effectiveness of this asymmetric reaction. In addition, N,N-isopropyl group on chiral N-phosphonylimine auxiliary was proven to be superior to other protecting groups in controlling diastereoselectivity.

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عنوان ژورنال:
  • Organic & biomolecular chemistry

دوره 8 5  شماره 

صفحات  -

تاریخ انتشار 2010