文摘

This paper describes the X-ray crystal structure of the diastereomeric complexes formed by enantiopure dimethyl-substituted acridino-18-crown-6 ether (R,R)-1 and the enantiomers of 1-(1-naphthyl)ethylammonium perchlorate. We found that the heterochiral complex (R,R)-1–(S)-1-NEA is more stable than the homochiral one (R,R)-1–(R)-1-NEA. In the case of the heterochiral complex, the X-ray studies revealed a strong intermolecular π–π interaction between the naphthyl unit and the acridine moiety. However, in the case of the homochiral complex, π–π interaction was not found. We suggest that the existence or absence of the π–π interaction and the difference in steric repulsions in the diastereomers is responsible for the enantiomeric discrimination.