Organocatalytic Nucleophilic Addition of Hydrazones to Imines: Synthesis of Enantioenriched Vicinal Diamines
作者:Yang Wang、Qian Wang、Jieping Zhu
DOI:10.1002/anie.201702295
日期:2017.5.8
catalytic amount of chiral phosphoric acid, nucleophilicaddition of N‐monosubstituted hydrazones to N‐Boc imines affords differentially protected vicinal diamines in the form of β‐amino N,N′‐dialkyldiazenes in excellent yields with high chemo‐, diastereo‐, and enantioselectivity. This catalytic asymmetric aza‐Mannich reaction represents the first example in which N‐alkyl hydrazones serve as α‐azo carbanion
A Formal Enantioselective Acetate Mannich Reaction: The Nitro Functional Group as a Traceless Agent for Activation and Enantiocontrol in the Synthesis of β-Amino Acids
作者:Bo Shen、Jeffrey N. Johnston
DOI:10.1021/ol801797h
日期:2008.10.16
procedure involving the enantioselective addition of alpha-nitro esters to imines, followed by reductive denitration, provides a convenient newenantioselective synthesis of beta-amino acids. Specifically, beta-phenyl alanine derivatives with up to 98% ee are formed in good yield (64-88%) over two steps. The utility of the approach is demonstrated through the first enantioselective synthesis of the key