Download PDF
Synthesis 1999; 1999(2): 286-289
DOI: 10.1055/s-1999-3396
paper
© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

Synthesis of Optically Active Indolizidines: (-)-8a-epi-Dendroprimine and (-)-7,8-Dehydro-5,6-dimethylindolizidine

Michel Diederich* , Udo Nubbemeyer
  • *Inst. für Organische Chemie, Freie Universität Berlin, Takustr. 3, D-14195 Berlin; Fax +49(30)8 38 51 63; E-mail: udonubb@chemie.fu-berlin.de
Further Information

Publication History

Publication Date:
31 December 1999 (online)

  PDF Download  Permissions and Reprints All articles of this category

Indolizidinones can be employed as key intermediates in efficient asymmetric synthesis of naturally occurring indolizidine alkaloid analogues. The 5,7-dimethylindolizidine (-)-8a-epi-dendroprimine was formed by a diastereoselective methylation-reduction sequence of the lactam function. The (-)-5,6-dimethylindolizidine was generated via the same key step including an additional quasi 1,2-methyl shift: an intramolecular enamine alkylation is followed by regioselective reductive cyclopropane ring opening.

indolizidinone - indolizidine - intramolecular enamine alkylation - iminium salt - diastereoselective reduction - radical cyclopropane opening

      >