Download PDF
Synthesis 1997; 1997(6): 673-676
DOI: 10.1055/s-1997-1399
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.

The Reaction of an α-Oxophosphonium Ylide with Halogens: 2,3-Disubstituted Diethyl Butenedioates from Diethyl 2-Oxo-3-triphenylphosphoranylidenebutanedioate

António M. d'A. Rocha Gonsalves1 , Ana M.T.D.P.V. Cabral2 , Teresa M.V.D. Pinho e Melo2 , Thomas L. Gilchrist3
  • 1Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3000 Coimbra, Portugal, Fax +351(39)26068; E-mail: arg@gemini.ci.ue.pt
  • 2Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3000 Coimbra, Portugal
  • 3Chemistry Department, University of Liverpool, P.O. Box 147, Liverpool L69 3BX, UK
Further Information

Publication History

Publication Date:
31 December 2000 (online)

  PDF Download  Permissions and Reprints All articles of this category

The title ylide 1 reacts with chlorine and with bromine in the presence of a range of nucleophiles. Triphenylphosphine oxide is eliminated and 2,3-disubstituted ethyl butenedioates 2-5 are isolated in moderate to good yield. The structure of one product, diethyl (Z)-2-acetoxy-3-bromobutenedioate (3a), has been established by X-ray crystallography. Similar reactions between the ylide 1 and N-bromosuccinimide and N-chlorosuccinimide in methanol or in the presence of azidotrimethylsilane give the diesters 6-8. Several of the reactions are highly stereoselective whereas others give both (E)- and (Z)-isomers.

stereoselectivity - phosphorous ylides - tetrasubstituted alkenes

      >