Mechanistic implications of the enantioselective addition of alkylzinc reagents to aldehydes catalyzed by nickel complexes with α-amino amide ligands

摘要: The enantioselective alkylation of aldehydes catalysed by nickel(ii)-complexes derived from α-amino amides was studied means density functional theory (DFT) and ONIOM (B3LYP:UFF) calculations. A mechanism proposed in order to investigate the origin enantioselectivity. chirality-determining step for formation intermediate complexes with involvement a 5/4/4-fused tricyclic transition state. predominant products predicted theoretically were (S)-configuration, good agreement experimental observations. scope reaction examined high yields enantioselectivities observed addition Et2Zn Me2Zn aromatic aliphatic aldehydes.