Because N to C carboxyl migration is precedented in acyclic amino acid derivatives, 25 and is known with 2-lithioaziridines that lack the stabilizing 2-alkoxycarbonyl group, 21 and 23 it might also occur with aziridine enolates. If the relatively strained bicyclic transition state for migration is accessible below the decomposition temperature, then a convenient synthesis of 2-substituted aziridine carboxylates may be possible from stable, readily available precursors.
