BRANDL, G and KASTNER, F and FRITSCH, R and ZINNER, H and MANNSCHRECK, A (1992) CHIROPTICAL DETECTION DURING LIQUID-CHROMATOGRAPHY .5. ONLINE MEASUREMENT OF CIRCULAR-DICHROISM SPECTRA-DELTA-EPSILON-LAMBDA DURING STOPS OF CHROMATOGRAPHIC FLOW. MONATSHEFTE FUR CHEMIE, 123 (11). pp. 1059-1069. ISSN 0026-9247,
Full text not available from this repository.Abstract
A procedure is described which serves to measure circular dichrograms DELTAepsilon (lambda) on line during stops of flow in liquid chromatography. Since the concentration of substrate in the spectrometer cell during the stop is not known, the differential absorption coefficients DELTAepsilon are calculated from the experimental differential absorbances DELTAA by means of UV absorption (i.e. photomultiplier voltage) data. Verifications of the procedure are obtained by its application to three substrates (Table 1), the DELTAepsilon (lambda) spectra of which were known. The present on-line technique is compared with a corresponding off-line method. The N,N-dimethylthiobenzamides 1 and 2 as well as the 9,10-phenanthrenequinone 7 consist of interconvertible enantiomers because their planar states are destabilized by steric overcrowding of groups. The unknown dichrograms DELTAepsilon (lambda) of 1, 2 and 7 are obtained (Figs. 2 and 4) and discussed with reference to the helicities of these molecules.
| Item Type: | Article |
|---|---|
| Uncontrolled Keywords: | ABSOLUTE-CONFIGURATION; ROTATIONAL BARRIERS; ENANTIOMERS; TRIACETYLCELLULOSE; SEPARATION; ENRICHMENT; HPLC; CIRCULAR DICHROISM SPECTRA; LIQUID CHROMATOGRAPHY ON OPTICALLY ACTIVE SORBENTS; 9,10-PHENANTHRENEQUINONES, ENANTIOMERS OF; THIOBENZAMIDES, ENANTIOMERS OF |
| Depositing User: | Dr. Gernot Deinzer |
| Last Modified: | 19 Oct 2022 08:44 |
| URI: | https://pred.uni-regensburg.de/id/eprint/54316 |
Actions (login required)
 |
View Item |
