Asymmetric Isothiourea-Catalysed Formal [3+2] Cycloadditions of Ammonium Enolates with Oxaziridines

نویسندگان

  • Siobhan R Smith
  • Charlene Fallan
  • James E Taylor
  • Ross McLennan
  • David S B Daniels
  • Louis C Morrill
  • Alexandra M Z Slawin
  • Andrew D Smith
چکیده

A highly enantioselective Lewis base-catalysed formal [3+2] cycloaddition of ammonium enolates and oxaziridines to give stereodefined oxazolidin-4-ones in high yield is described. Employing an enantioenriched oxaziridine in this process leads to a matched/mis-matched effect with the isothiourea catalyst and allowed the synthesis of either syn- or anti-stereodefined oxazolidin-4-ones in high d.r., yield and ee. Additionally, the oxazolidin-4-one products have been derivatised to afford functionalised enantioenriched building blocks.

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عنوان ژورنال:

دوره 21  شماره 

صفحات  -

تاریخ انتشار 2015