engleski

Asymmetric synthesis of beta-lactams by chiral ester enolate-imine condensation

Asymmetric cyclocondensation of N, N-bis(silyl)glycinates bearing chiral ester moieties with aldimines is found to proceed with extremely high enentioselectivity to give the corresponding chiral beta-lactams in good to high yields. It is found that the E/Z-geometry of the chiral ester-enolate is responsible for cis/trans stereochemistry of the beta-lactam formed. Effects of various chiral auxiliaries in the ester-enolates or the aldimines on the enentioselectivity of the reactions will be discussed.

beta-lactams; chiral ester enolate-imine condensation

nije evidentirano