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

ABSTRACT: The application of polystyrene-immobilized proline-based catalysts in packed-bed reactors for the continuous-flow, direct, enantioselective ?-aminoxylation of aldehydes is described. The system allows the easy preparation of a series of ?-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.

SUBMITTER: Cambeiro XC

PROVIDER: S-EPMC3252847 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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

Cambeiro Xacobe C XC Martín-Rapún Rafael R Miranda Pedro O PO Sayalero Sonia S Alza Esther E Llanes Patricia P Pericàs Miquel A MA

Beilstein journal of organic chemistry 20111031

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. ...[more]

PMID: 22238521

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