CHED 799 |
| Patricia J. Galarza and Konstantinos Kavallieratos. Department of Chemistry and Biochemistry, Florida International University, University Park, Miami, FL 33199 |
| Enantioselective synthesis and catalysis is a vibrant field of synthetic chemistry. Many successful examples have been reported, which often involve metal complexes of chiral ligands. Simpler chiral auxiliaries have been used in the past with spectacular results. Extending our previous work on chiral sulfonamide anion receptors, we now report the synthesis and characterization of new chiral carboxamides, which could find application in the enantioselective catalysis of reactions involving anionic transition states. They are derived from simple frameworks (isophthaloyl dichloride, 2,6-pyridinedicarbonyl chloride) and the chiral amines, (R)-(+)-Bornylamine, (1R,2S)-(+)-cis-1-Amino-2-indanol, (1S,2R)-(-)-cis-1-Amino-2-indanol, (R)-(+)-α-(1-Naphthylethyl)amine, and (S)-(-)-α-(1-Naphthylethyl)amine. Anion binding via hydrogen bonding was demonstrated by 1H-NMR spectroscopy. Association constants for anion binding were determined by 1H-NMR titrations with tetrabutylammonium salts of the corresponding anions. The association constants Ka were found to be as high as 10,000 M-1 for the acetate complex of the (1S,2R)-(-)-cis-1-Amino-2-indanol amide derivative. More significantly, the carboxamide derivatives of (1S,2R)-(-)-cis-1-Amino-2-indanol and of (1R,2S)-(+)-cis-1-Amino-2-indanol, were found to bind tetrabutylammonium L-lactate with association constants of 520 M-1 and 145 M-1 respectively, indicating chiral recognition. |
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Undergraduate Research Poster Session: Organic Chemistry
2:00 PM-4:00 PM, Monday, March 29, 2004 Anaheim Convention Center -- Hall A, Poster
Division of Chemical Education |