An enantioselective strategy for the total synthesis of (S)-tylophorine via catalytic asymmetric allylation and a one-pot DMAP-promoted isocyanate formation/Lewis acid catalyzed cyclization sequence.

نویسندگان

  • Bo Su
  • Hui Zhang
  • Meng Deng
  • Qingmin Wang
چکیده

A new asymmetric total synthesis of a phenanthroindolizidine alkaloid (S)-tylophorine is reported, which features a catalytic asymmetric allylation of aldehydes and an unexpected one-pot DMAP promoted isocyanate formation and Lewis acid catalyzed intramolecular cyclization reaction. In addition, White's direct C-H oxidation catalyst system converting monosubstituted olefins to linear allylic acetates was also employed for late-stage transformation.

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عنوان ژورنال:
  • Organic & biomolecular chemistry

دوره 12 22  شماره 

صفحات  -

تاریخ انتشار 2014