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This article is based on a review of literature devoted to the phenomenon of SDE via achiral chromatography since the appearance of the seminal work of Professor Emanuel Gil-Av. The discussed examples of chromatographic studies are related to amides derived from chiral amines and α- and β-amino acids. We discuss the observed SDE magnitude as a function of a compound's structure, and composition of eluent and stationary phases, providing some mechanistic considerations. Particular emphasis is given to the aspect of SDE via achiral chromatography as an emerging unconventional enantiomeric purification technique. [ABSTRACT FROM AUTHOR]

We report the best performance yet for the self-disproportionation of enantiomers (SDE) via achiral chromatography as typically used in laboratories for the isolated yield of the excess enantiomer using N-acetyl β-amino acid ethyl esters. The results are the most convincing ever demonstration of the capability of the SDE for practical-scale enantiopurification as comparable, or even superior for some systems, to that of recrystallization. For example, from a sample of 94.4 % ee, a yield of 71 % of enantiopure material was isolated in a single chromatographic run. Moreover, the lack of an esoteric structural entity, e.g. strongly polarizing groups, such as, for instance CF, highlights the fact that the phenomenon is not dependent on the presence of such and thus the process is relevant to any usual-type structure. In contrast to recrystallization, the procedure is predictable, general, and dependable, boding well for its widespread application in routine laboratory settings. [ABSTRACT FROM AUTHOR]

The study of the self-disproportionation of enantiomers (SDE) via gravity-driven achiral column chromatography of a series of N -fluoroacetylated amides derived from 1-phenylethylamine is described. The chromatographic experiments performed with N -fluoroacetylated amides confirmed, that the process of molecular association in solution leading to the SDE manifestation, is sensitive to the fluorine content and type of solvent used. Thus, the two opposite eluting profiles for the same compound were observed in two different eluents. Moreover, the amides bearing perfluoroalkyl groups showed opposite eluting order as compared to the established profile for fluorine-free N -acetyl-1-phenylethylamine. [ABSTRACT FROM AUTHOR]