Synthesis of gamma-butyrolactams by photoinduced PhSe group transfer radical cyclization and formal synthesis of (+/-)-isocynometrine with diphenyldiselenide as promoter

J Org Chem. 2009 Nov 20;74(22):8610-5. doi: 10.1021/jo9017099.


We have developed a strategy for constructing nitrogen heterocycles by photoinduced PhSe group transfer radical cyclization. trans-Alpha,beta-disubstituted gamma-butyrolactams (2-pyrrolidinones) were prepared in good yields (38-73%) with high regioselectivity and stereoselectivity from N-alkenyl alpha-PhSe beta-keto amides. Reaction outcomes were modulated by the steric effect of the substituents on the nitrogen atom of the cyclization precursors and the stereoelectronic effect of the substrates. Diphenyldiselenide, as an additive, was found to promote ring closure. The advantage of this strategy in natural product synthesis is demonstrated by a formal synthesis of (+/-)-isocynometrine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 4-Butyrolactone / analogs & derivatives
  • 4-Butyrolactone / chemical synthesis*
  • 4-Butyrolactone / chemistry
  • Alkaloids / chemical synthesis*
  • Alkaloids / chemistry
  • Cyclization
  • Free Radicals / chemistry
  • Imidazoles / chemical synthesis*
  • Imidazoles / chemistry
  • Molecular Structure
  • Organoselenium Compounds / chemistry*
  • Photochemistry
  • Stereoisomerism


  • Alkaloids
  • Free Radicals
  • Imidazoles
  • Organoselenium Compounds
  • isocynometrine
  • 4-Butyrolactone