Recognition by New Pyridino-18-crown-6 Ligands Containing Two Methyl, Two t-Butylor Two Allyl Substituents on Chiral Positions Next to the Pyridine Ring for the Enantiomers of Chiral Organic Ammonium Perchlorates

摘要

The log K values for the interaction of new chiral pyridino-18-crown-6 ligandscontaining two substituents on chiral positions next to the pyridine ring with the enantiomers of a-phenylethylamonium perchlorate (PhEt) and a-(1-naphthyl)ethylammonium perchlorate (NapEt) were measured using a (1)H NMR titration method in a CDCl3/CD3OD (1/1) solvent mixture. The log K values indicate that these chiral pyridino-18-crown.-6 ligands have high complexing abilities and good enantiomeric recognition for the chiral organic ammonium perchiorates. The (1)H NMR titration experiments also show that the phenyl ring