Asymmetric synthesis of β-lactams by chiral ester enolate - imine condensation
作者:Iwao Ojirna、Ivan I-Iabus
DOI:10.1016/s0040-4039(00)97603-2
日期:1990.1
Asymmetric cyclocondensation of N,N-bis(silyl)glycinates bearing chiral ester moieties with aldimines is found to proceed with extremely high enantioselectivity to give the corresponding chiral β-lactams in good to high yields. It is found that the E/Z-geometry of the chiral ester-enolate ts responsible for cis/trans stereochemistry of the β-lactam formed. Effects of various chiral auxiliaries in the