Enantioseparation of amino compounds by derivatization with o-phthalaldehyde and d-3-mercapto-2-methylpropionic acid

Abstract o -Phthalaldehyde in combination with d -3-mercapto-2-methylpropionic acid is described as a chiral reagent for the enantioseparation of amino compounds. The reagent was applied to the optical resolution of α-amino acids, α-alkyl-α-amino acids, α-amino acid amides, α-alkyl-α-amino acid amides, β-amino alcohols and β-alkyl-β-amino alcohols. Separation of the diastereomers was carried out by reversed-phase chromatography and the derivatives were detected fluorimetrically. The diastereoselectivity obtained was compared with that of other commercially available chiral thiols. The rate of the reaction of various amino compounds with o -phthalaldehyde- d -3-mercapto-2-methylpropionic acid was studied, together with the stability of the derivatives obtained. Application of the method to the enantioseparation of chiral monofunctional amines was demonstrated by using α-methylbenzylamine as a model compound. The method described offers good enantioselectivity combined with high sensitivity for various chiral amino compounds derived from chemo-enzymatic processes.