ISSN:
0749-1581
Keywords:
NMR
;
1H NMR
;
chiral shift reagents
;
meso isomers
;
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
In the presence of chiral shift reagents the enantiotopic nuclei of a pair of enantiomers become diastereotopic and have the potential to give resolved NMR signals. Similarly, the enantiotopic nuclei within a meso isomer become diastereotopic in the presence of a chiral shift reagent and may give resolved NMR signals. However, the diastereotopic nuclei of a meso isomer mixed with a chiral shift reagent, unlike those of a racemic mixture, are located in the same molecule. Their intramolecular character can be established experimentally by detection of spin-spin splitting between them or to a common third nucleus. Comparison of the correlation peaks in a two-dimensional, heteronuclear, multiple-quantum correlation (HMQC) spectrum with those of a heteronuclear multiple-bond correlation (HMBC) spectrum is an effective means of detection of coupling to a third nucleus. Two-dimensional NMR spectroscopy was used to identify the meso form of di-(trans-2-aminocyclohexyl)amine.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1260331112
Permalink