An efficient, overall enantioselective variant of the Hantzsch synthesis of 4-aryl-1,4-dihydropyridines (ee = 84 - 98%), important biologically active compounds (eg as calcium channel blockers), is described. Key step of the new procedure is the asymmetric Michael addition of metalated chiral alkyl acetoacetate hydrazones ( )- to the Knoevenagel acceptors . An accurate method to determine the enantiomeric excess of chiral dihydropyridines is also reported.
