Chiral <i>N</i>-Acylethylenediamines as New Modular Ligands for the Catalytic Asymmetric Addition of Alkylzinc Reagents to Aldehydes
作者:Christopher M. Sprout、Christopher T. Seto
DOI:10.1021/jo0347516
日期:2003.10.1
Chiral N-acylethylenediamines represent a new class of modular ligands for the catalytic asymmetric addition of alkylzincreagents to aldehydes. The N-acylethylenediamine moiety serves as a metal binding site, while attached amino acids provide the source of chirality. Three sites of diversity on the ligands were optimized to enhance the enantioselectivity of the catalysts using an iterative optimization
Solid-Phase Synthesis of Chiral <i>N</i>-Acylethylenediamines and Their Use as Ligands for the Asymmetric Addition of Alkylzinc and Alkenylzinc Reagents to Aldehydes
作者:Christopher M. Sprout、Meaghan L. Richmond、Christopher T. Seto
DOI:10.1021/jo049160+
日期:2004.10.1
synthesis of chiral N-acylethylenediamine ligands. The ligands are obtained in good yield and purity, without the need for chromatography or other purification methods. Several new and previously reported ligands were prepared using this procedure. These compounds were examined as catalysts for the enantioselectiveaddition of alkylzincreagents to aldehydes. In all cases, the crude ligands from the solid-phase