the condensation of N′-benzylbenzoylhydrazide with a variety of aldehydes in the presence of a catalytic amount of an axiallychiraldicarboxylicacid. By trapping these electrophiles with alkyl diazoacetate or (diazomethyl)phosphonate nucleophiles, we produced a diverse array of chiral α-diazo-β-hydrazino esters and phosphonates with excellent enantioselectivities.