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Enantioselective Addition of Bromonitromethane to Aliphatic N-Boc Aldimines Using a Homogeneous Bifunctional Chiral Organocatalyst.

ABSTRACT: This report details the enantioselective synthesis of ?-amino-?-bromo nitroalkanes with ?-alkyl substituents, using homogeneous catalysis to prepare either antipode. Use of a bifunctional Brønsted base/acid catalyst allows equal access to either enantiomer of the products, enabling the use of Umpolung Amide Synthesis (UmAS) to prepare the corresponding L- or D-?-amino amide bearing alkyl side chains - overall, in only 4 steps from aldehyde. The approach also addresses an underlying incompatibility between bromonitromethane and solid hydroxide bases.

SUBMITTER: Schwieter KE

PROVIDER: S-EPMC4807613 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Enantioselective Addition of Bromonitromethane to Aliphatic N-Boc Aldimines Using a Homogeneous Bifunctional Chiral Organocatalyst.

Schwieter Kenneth E KE Johnston Jeffrey N JN

ACS catalysis 20150101 11

This report details the enantioselective synthesis of β-amino-α-bromo nitroalkanes with β-alkyl substituents, using homogeneous catalysis to prepare either antipode. Use of a bifunctional Brønsted base/acid catalyst allows equal access to either enantiomer of the products, enabling the use of Umpolung Amide Synthesis (UmAS) to prepare the corresponding L- or D-α-amino amide bearing alkyl side chains - overall, in only 4 steps from aldehyde. The approach also addresses an underlying incompatibili ...[more]

PMID: 27019764

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