| Abstract: | Enantioselective resolution is realized by combining potentiometry with ligand exchange (CE) in a new method called chiral ligand exchange potentiometry (CLEP). A chiral selector, N‐carbobenzoxy‐L ‐aspartic acid (N‐CBZ‐L‐Asp), preferentially recognizes D ‐aspartic acid (D‐Asp) and undergoes ligand exchange with the enantiomeric labile coordination complexes of [Cu(II)(D‐Asp)2] or [Cu(II)(L‐Asp)2] to form a diastereoisomeric complex [(D‐Asp)Cu(II)(N‐CBZ‐L‐Asp)] (a) or [(L‐Asp)Cu(II)(N‐CBZ‐L‐Asp)] (b). Considerable stereoselectivity occurs in the formation of these diastereoisomeric complexes, and their net charges were ?2 (a) and 0 (b), respectively, resulting in different Nernst factor (electrode slope), thus enabling chiral D‐Asp to be distinguished by potentiometry without any pre‐ or postseparation processes. |
