title: Enantioselective Addition of Bromonitromethane to AliphaticN-Boc Aldimines Using a Homogeneous Bifunctional Chiral Organocatalyst.
abstract: 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 incompatibility between bromonitromethane and solid hydroxide bases.
authors.forename: Kenneth E
authors.initials: KE
authors.lastname: Schwieter
authors.forename: Jeffrey N
authors.initials: JN
authors.lastname: Johnston
keywords: enantioselective catalysis; homogeneous catalysis; organocatalysis; peptides; umpolung amide synthesis