Darzens Reaction of Acyl Phosphonates with alpha-Bromo Ketones: Selective Synthesis of cis- and trans-Epoxyphosphonates

DEMİR A. G., Emrullahoglu M., Pirkin E., Akca N.

JOURNAL OF ORGANIC CHEMISTRY, vol.73, no.22, pp.8992-8997, 2008 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 73 Issue: 22
  • Publication Date: 2008
  • Doi Number: 10.1021/jo801818p
  • Journal Name: JOURNAL OF ORGANIC CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.8992-8997
  • Middle East Technical University Affiliated: Yes

Abstract

Acyl phosphonates with alpha-halo ketones in the presence of bases at room temperature afford cis- and trans-epoxyphosphonates in good chemical yields and high selectivities using different bases. The diastereoselectivity of this reaction is easily controlled by changing the base. Changing the base from CS(2)CO(3) to DBU changed the diastereomeric ratio (trans/cis) from 3/2 to 9/1. Moreover, the treatment of the trans isomer with DBU showed a complete conversion to the corresponding cis isomer.