The efficient resolution of racemic N-benzyl α-amino acids (N-Bn-AA) has been achieved by a liquid-liquid extraction process using the lipophilic chiral salen-cobalt(III) complex [Co III (3)(OAc)]. As a result of the resolution by extraction, one enantiomer (S) of the N-benzyl α-amino acid predominated in the aqueous phase, while the other enantiomer (R) was driven into the organic phase by complexation to cobalt. The complexed amino acid (R) was then quantitatively released by a reductive (Co III Ǟ Co II ) counter-extraction with aqueous sodium dithionite or L-ascorbic acid in methanol. The reductive cleavage allowed to recover the [Co II (3)] complex in good yield, which could be easily re-oxidized to [Co III (3)(OAc)] with air/AcOH and reused with essentially no loss of reactivity and selectivity. Investigation on the nitrogen

Liquidating the assets: Coordination of one enantiomer from a racemic mixture of N‐benzyl α‐amino acids (N‐Bn‐AA) to the lipophilic chiral [CoIII(salen)(OAc)] complex results in its extraction into the organic phase. The enantiomer can then be released in excellent yield and high enantiomeric excess by reductive counterextraction. The cobalt(III) complex can be regenerated and re‐used without loss of reactivity or selectivity.

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