Enantiomerically pure (𝑅,𝑅)-(+)-2,3-diphenylpiperazine with 98% $ee$ was obtained by resolution of the corresponding racemic mixture using ($1S$)-(+)-10-camphorsulfonic acid. The partially resolved enriched sample of (𝑆,𝑆)-(-)-2,3-diphenylpiperazine with 73% ee was purified to obtain samples of 97% ee using different achiral acids via the preparation of either homochiral or heterochiral hydrogen bonded aggregates.

Efficient use of the readily accessible chiral $C_2$-symmetric acyclic diamines (1-2) as well as macrocyclic amines (3-5) containing trans-1,2-diaminocyclohexyl moiety as chiral solvating agents (CSA) for the determination of enantiomeric excess of representative carboxylic acids (6-7) and an amino acid derivative (8) is illustrated. The enantiomeric composition of different carboxylic acids estimated here by the ¹H NMR method, based on the integration of the corresponding methine proton signals are in good correlation with that determined using HPLC method. The data are in accordance with the formation of multimolecular diastereomeric complexes in solution, which render good splitting of NMR signals for the enantiomers of representative carboxylic acids as well as for 𝑁-Ts-phenylglycine (up to $\Delta \Delta \delta = 0.295$ ppm, 118 Hz).