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Readily available L-tartaric acid, which is a bidentate ligand with two chiral centers forming a seven-membered chelate ring, was applied to the chiral ligand for the chiral (NMR) shift reagent of samarium(III) formed in situ. This simple method does not cause serious signal broadening in the high magnetic field. Enantiomeric 13C and 1H NMR signals and enantiotopic 1H NMR signals of α-amino acids were successfully resolved at pH 8.0 and the 1:3 molar ratio of Sm(NO3)3:L-tartaric acid. It is elucidated that the enantiomeric signal resolution is attributed to the anisotropic magnetic environment for the enantiomers induced by the chiral L-tartarato samarium(III) complex rather than differences in stability of the diastereomeric substrate adducts. The present 13C NMR signal resolution was also effective for the practical simultaneous analysis of plural kinds of DL-amino acids. Chirality 27:353-357, 2015.© 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Experimental conditions for determination of enantiomeric composition of 1-substituted 3-aminocarboranes by 1H and 13C NMR spectroscopy using chiral shift reagent Eu(hfc)3 have been found. [Copyright &y& Elsevier]