An efficient and highly anti-diastereo-(de=90–≈100%) and enantioselective (ee=92–≈100% ) synthesis of 3,4-disubstituted 5-oxo-alkanoates in good overall chemical yields is described. The procedure involves the asymmetric Michael addition of aldehydes or ketones to enoates via their lithiated SAMP-/RAMP-hydrazones. Both enantiomers are accessible at will. ... The 1.4-addition of aldehydes and ketones to enoates in excellent asymmetric ...