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On the solvent versatility in immobilized amylose tris(3,5-dimethylphenylcarbamate) chiral stationary phase in high performance liquid chromatography: Application to the asymmetric cyclopropanation of olefins
journal contribution
posted on 2023-05-17, 00:15 authored by Ghanem, A, Aboul-Enein, HYThe enantioseparation of a set of cyclopropanes derived from Meldrum's acid and 3,3,3-trifluoro-2-diazopropionate has been achieved on the new immobilized amylose tris(3,5-dimethylphenylcarbamate) chiral stationary phase (Chiralpak IA) in high performance liquid chromatography (HPLC) using a mixture of n-hexane–2-propanol (90:10, or 99:1, v/v) as mobile phase with a flow-rate of 0.5 ml/min and UV detection at 254 nm. Due to its ability to withstand prohibited HPLC solvents like dichloromethane, an online HPLC equipped with a sensitive optical rotation detector for monitoring the optical activity of the racemic and enantioenriched cyclopropanes prepared via the Rh(II)-catalyzed asymmetric inter- and intramolecular cyclopropanations in dichloromethane is demonstrated. Direct analysis techniques without further purification, workup or removal of dichloromethane were summarized. The method provides an easy and direct determination of the enantiomeric excess of the cyclopropanes and selectivity of the catalyst used without any further work up.
History
Publication title
Analytica Chimica ActaVolume
548Issue
1-2Pagination
26-32ISSN
0003-2670Department/School
School of Natural SciencesPublisher
Elsevier Science BvPlace of publication
Po Box 211, Amsterdam, Netherlands, 1000 AeRights statement
The definitive version is available at http://www.sciencedirect.comRepository Status
- Restricted