Tandem double-Michael-addition/cyclization/acyl migration of 1,4-dien-3-ones and ethyl isocyanoacetate: stereoselective synthesis of pyrrolizidines

Angew Chem Int Ed Engl. 2009;48(16):2868-72. doi: 10.1002/anie.200805703.

Abstract

Up to four adjacent stereocenters can be formed stereoselectively in the construction of a pyrrolizidine unit through a novel organocatalytic reaction that involves treatment of various dienones with ethyl isocyanoacetate (see scheme; DBU = 1,8-diazabicyclo[5.4.0]undec-7-ene). Mechanisms for this atom-economic, one-pot synthesis have been proposed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Cyclization
  • Isocyanates / chemistry*
  • Pyrrolizidine Alkaloids / chemical synthesis*
  • Pyrrolizidine Alkaloids / chemistry
  • Stereoisomerism

Substances

  • Isocyanates
  • Pyrrolizidine Alkaloids