An improved method for determining enantiomeric excess by 13C-NMR in chiral liquid crystal media
Autor: | Vasilios M. Marathias, Nikolaos Papaioannou, Walter W. Massefski, Peter A. Tate |
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Rok vydání: | 2010 |
Předmět: |
Pharmacology
Magnetic Resonance Spectroscopy Time Factors Chromatography Chemistry organic chemicals Organic Chemistry Enantioselective synthesis Analytical chemistry Chemical modification Stereoisomerism Carbon-13 NMR Small molecule Catalysis Spectral line Liquid Crystals Analytical Chemistry Solvent Liquid crystal Drug Discovery polycyclic compounds heterocyclic compounds Enantiomeric excess Spectroscopy |
Zdroj: | Chirality. 22:838-843 |
ISSN: | 0899-0042 |
Popis: | By using a combination of inverse gated (1)H decoupled (13)C-NMR experiments1 with short acquisition times and NMR Cryo-probe technology, the sample requirements and experimental times necessary to accurately measure enantiomeric excess of small chiral molecules has been reduced 16-fold. Quality (13)C-NMR spectra can now be obtained from a 1 to 5 mg sample in 12 minutes. The enantiomeric excess determination achieved from the average integration of all the (13)C-resonances in the spectrum is comparable to enantiomeric excess measured by chiral SFC. The advantage of the NMR method is that enantiomeric excess can rapidly be measured in situ on practical amounts of enantioselective reaction products without the need for chromatographic separation or chemical modification and with substantially less solvent waste. |
Databáze: | OpenAIRE |
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