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The enantioselectivity of chiral macrocyclic polyamides 1 – 3 derived from L-/D-tartaric acid was investigated by using 1 H NMR. All the macrocycles exhibited certain chiral recognition towards the enantiomers of the racemic carboxylic acids we had chosen. As a chiral solvating agent, the compound 3 has the excellent enantiomeric discriminating ability for mandelic acids and its derivatives, containing an α-OH at the chiral carbon, while the compound 2 has the best enantioselectivity towards dibenzoyltartaric acid. The molar ratio and the association constants of the compound 3 with each of the enantiomers of some guest molecules were determined by using the Job's plots and a nonlinear leastsquares fitting method, respectively. The effect of the structure of the hosts or guests on the enantioselectivity of the compound 1 – 3 has been explored. [ABSTRACT FROM AUTHOR]

Abstract: Two amphiphilic chiral receptors 2a and 2b were designed and synthesized. Both are efficient chiral solvating agents for chiral carboxylic acids. In particular, 2a is an excellent CSA not only for lipophilic guests, but also for some hydrophilic guests. It is the first CSA for the direct determination of the enantiomeric composition of hydrophilic chiral hydroxylated acid in protic polar solvent. [Copyright &y& Elsevier]

Abstract: A series of new compounds, (1R,2R)-1-(1′,8′-naphthalimide)-2-aminocyclohexane 1 and its 4′-derivatives 2 and 3 derived from (1R,2R)-1,2-diaminocyclohexane have been synthesized conveniently and efficiently. 1H NMR spectroscopy was employed to investigate their enantiodiscriminating ability. Compared with α-phenylethylamine, a commercially available chiral solvating agent (CSA), these compounds exhibited better enantiodiscriminating ability toward the chiral carboxylic acids we had chosen, distinguishing them as promising and practical CSAs. [Copyright &y& Elsevier]