ORGN 682 |
| Primary, secondary, and indiscriminately carboxymethylated derivatives of alpha-, beta-, and gamma-cyclodextrin are prepared and compared to native cyclodextrins for their effectiveness as chiral NMR discriminating agents. The anionic carboxymethylated cyclodextrins are especially effective for the analysis of cationic organic substrates. Enantiomeric discrimination with the indiscriminately substituted carboxymethylated cyclodextrin derivatives is larger than that with the secondary and primary derivatives. This is likely the result of the high degree of substitution with the indiscriminately substituted derivative. Paramagnetic lanthanide ions such as praseodymium(III) and ytterbium(III), when added solutions of the carboxymethylated cyclodextrins, complex with the carboxymethyl groups and cause pronounced enhancements in enantiomeric discrimination. |
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Asymmetric Reactions, Combinatorial Chemistry, Molecular Recognition and Self-Assembly, Proteins, Peptides, Amino Acids and Enzyme Inhibitors
8:00 PM-10:00 PM, Wednesday, March 28, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Organic Chemistry |