Recognition by New Pyridino-18-crown-6 Ligands Containing Two Methyl, Two t-Butyl or Two Allyl Substituents on Chiral Positions Next to the Pyridine Ring for the Enantiomers of Chiral Organic Ammonium Perchlorates.
Abstract
The log K values for the interaction of new chiral pyridino-18-crown-6 ligands containing 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 of the guest PhEt is almost parallel to the pyridine ring in the chiral diallyl- and dimethyl-substituted ligand complexes with chiral PhEt, and the phenyl ring is perpendicular to the pyridine ring in the chiral di-t-butyl-substituted ligand complex with PhEt. These results were supported by MM2 calculations.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1996
- Accession Number
- ADA309206
Entities
People
- J. J. Young
- Jerald S. Bradshaw
- Peter Huszthy
- Steven L. Castle
- Yoichi Habata
Organizations
- Brigham Young University