Journal
ANALYTICAL CHEMISTRY
Volume 81, Issue 9, Pages 3560-3570Publisher
AMER CHEMICAL SOC
DOI: 10.1021/ac802212s
Keywords
-
Categories
Funding
- Universita La Sapienza, Rome, Italy
- Istituto Pasteur Fondazione Cenci Bolognetti, Rome, Italy
Ask authors/readers for more resources
Second-order rate constants of the diethylamine-promoted enantiomerization of 2-[2-(1-methyl-1H-pyrrol-2-yl)-2-oxo-1-phenylethyl]-isoindole-1,3-dione, a chiral a-substituted ketone endowed with high anti-MAO activity type-A, were measured by dynamic high-performance liquid chromatography (DHPLC), stopped-flow high-performance liquid chromatography (sf-HPLC), and a classical method based on enantioselective HPLC as the monitoring tool. The chiral column used in all determinations was the commercial Chiralpak AD. By comparison of the obtained data, perturbing effects of the stationary phase on the DHPLC and sf-HPLC determinations were highlighted and distinguished in indirect (SPIPC) and direct (SPDPC) type. It was evidenced that SPDPC noise effects may be completely erased by simple mathematical treatment of data obtained at different concentrations of the basic catalyst. Perturbations of type SPIPC may instead only be partially kept down by modulating the concentration of the basic catalyst. An estimation of the density distribution of catalytic sites covalently bonded to the stationary phase (SP) of the Chiralpak AD was performed exploiting the quantified SPDPC effects. Such an approach might be of general application, supplying a useful way to characterize the attitude of SPs to speed acid- or base-catalyzed equilibria possibly active during chromatographic separations.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available