Continuous-flow enantioselective α-aminoxylation of aldehydes catalyzed by a polystyrene-immobilized hydroxyproline

نویسندگان

  • Xacobe C Cambeiro
  • Rafael Martín-Rapún
  • Pedro O Miranda
  • Sonia Sayalero
  • Esther Alza
  • Patricia Llanes
  • Miquel A Pericàs
چکیده

The application of polystyrene-immobilized proline-based catalysts in packed-bed reactors for the continuous-flow, direct, enantioselective α-aminoxylation of aldehydes is described. The system allows the easy preparation of a series of β-aminoxy alcohols (after a reductive workup) with excellent optical purity and with an effective catalyst loading of ca. 2.5% (four-fold reduction compared to the batch process) working at residence times of ca. 5 min.

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عنوان ژورنال:

دوره 7  شماره 

صفحات  -

تاریخ انتشار 2011