Asymmetric Michael Additions via SAMP‐/RAMP‐Hydrazones Enantioselective 1,4‐Addition of Methyl Ketones to Knoevenagel Acceptors1)

Asymmetric Michael addition of lithiated methyl ketone SAMP‐hydrazones (S)‐2 to 2‐benzylidenemalonates and ‐dinitriles 3 followed by oxidative cleavage of the 1,4‐adducts (SR)‐4 by ozonolysis affords 2‐substituted 4‐oxo diesters and ‐dinitriles (R)‐5 in good overall yields of 50–82% and high enantiomeric excesses (ee ≧ 95%).