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Updated: Sep 14, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Accessing N-Unprotected Unnatural α-Amino Acid Esters by Half-Sandwich Chiral-at-Ruthenium Aldehyde Catalysis: Scope
Gang Chen1, Gabriel N Morais2, Hui Liang1
1Frontiers Science Center for Transformative Molecules, National Key Laboratory of Innovative Immunotherapy, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, 200240, P.R. China.
Abstract:
Chiral aldehyde catalysis has emerged as an efficient and step-economical protocol for constructing unnatural α-amino acids and related esters. Herein, we report the application of a half-sandwich chiral-at-ruthenium complex featuring an aldehyde group as a versatile asymmetric catalyst with remarkably broad scope. Direct asymmetric α-C─H functionalization of N-unprotected glycine esters with four types of electrophiles (51 examples, all >91% ee) has been successfully realized for accessing structurally diverse unnatural α-amino acid esters. Gram-scale synthesis and successful catalyst recovery underscored the practicability and application potential of the present asymmetric aldehyde catalysis.
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