Mechanistic aspects of the isomerization of Z-vinylic tellurides double bonds in the synthesis of potassium Z-vinyltrifluoroborate salts

نویسندگان

  • Hélio A Stefani
  • Rafael C Guadagnin
  • Artur F Keppler
  • Giancarlo V Botteselle
  • João V Comasseto
  • Carlos A Suganuma
چکیده

Through direct transmetalation reaction of Z-vinylic tellurides with nBuLi was observed the unexpected isomerization of double bonds leading to potassium E-vinyltrifluoroborates salts in low to moderate yields. Using EPR spin trapping experiments the radical species that promoted the stereoinversion of Z-vinylic organometallic species during the preparation of potassium vinyltrifluoroborate salts was identified. The experiments support the proposed mechanism, which is based on the homolytic cleavage of the TenBu bond.

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عنوان ژورنال:
  • Beilstein Journal of Organic Chemistry

دوره 4  شماره 

صفحات  -

تاریخ انتشار 2008