Carboxylic acids, enantioseparation

For a quite long period of time, chiral ligand-exchange chromatography (CLEC) has been the standard method for the enantioseparation of free amino acids. Meanwhile, other methods became available for these target molecules, such as teicoplanin or chiral crown-ether-based CSPs. However, for the enantioseparation of aliphatic a-hydroxy carboxylic acids, it is still one of the most efficient methods. 

Figure 13.15 Enantioseparation of selected carboxylic acids and other acidic compounds 40-53.

Uray, G., Maier, N.M. Diphenylethane-diamine (DPEDA) derivatives as chiral selectors. VI. Enantioseparation ofunder-ivatized aryl substituted carboxylic acids on four differently linked N-3,5-dinitro-benzoyl-DPEDA derived CSPs, Enantiomer, 1996,1, 211-217. 

Sinibaldi, M., Flieger, M., Cvak, L., Messina, A. and Pichini, A. (1994) Direct resolution of optically active isomers on chiral packings containing ergoline skeletons. II. Enantioseparation of carboxylic acids. /. Cbromatogr. A, 666, 471-478. 

The major area of applications of cinchona 9-O-carbamate type CSPs embraces enantioseparation of diverse N-protected amino acids and peptides, carboxylic, phosphonic, and phosphoric acids as well as other acidic compounds. 

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