The dynamic kinetic resolution (DKR) of a zirconaaziridine with (R,R)-diphenylethylene carbonate (R,R-DPEC, an optically active CO₂ synthon) yields a zirconacycle; methanolysis gives an enantioenriched amino acid methyl ester.  The maximum ee is attained when the rate of zirconaaziridine enantiomer interconversion is much faster than the rate of reaction of either enantiomer with R,R-DPEC.  In order to decide if such a DKR is possible, the rate of enantiomer interconversion must be known.  We have measured that rate by using the reaction below to produce optically enriched zirconaaziridines and monitoring their racemization by CD.