Reactions of alpha,beta-enones with diazo compounds part 3 on the nature of the 1,5-ring closure of alpha,beta-enone ylides

Anac O. , Ozdemir A. , SEZER Ö.

HELVETICA CHIMICA ACTA, vol.86, no.2, pp.290-298, 2003 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 86 Issue: 2
  • Publication Date: 2003
  • Doi Number: 10.1002/hlca.200390030
  • Title of Journal : HELVETICA CHIMICA ACTA
  • Page Numbers: pp.290-298


Carbonyl ylides arising from ethyl acetodiazoacetate/dimethyl diazomalonate and a,beta-enones with mainly s-cis conformations underwent disrotatory cyclization to produce dihydrofuran derivatives. This process proved to be sensitive to steric effects. The corresponding ylides arising from rather s-trans a,beta-enals yielded dioxole derivatives. The mechanisms of the reactions are discussed.