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Updated: Mar 17, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Photofragmentation mechanisms in protonated chiral cinchona alkaloids
Sunil Kumar1, Bruno Lucas1, Jacqueline Fayeton1
1Institut des Sciences Moléculaires d'Orsay (ISMO), CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France. anne.zehnacker-rentien@u-psud.fr.
Abstract:
The photo-stability of protonated cinchona alkaloids is studied in the gas phase by a multi-technique approach. A multi-coincidence technique is used to demonstrate that the dissociation is a direct process. Two dissociation channels are observed. They result from the C8-C9 cleavage, accompanied or not by hydrogen migration. The branching ratio between the two photo-fragments is different for the two pseudo-enantiomers quinine and quinidine. Mass spectrometry experiments coupling UV photo-dissociation of the reactants and structural characterization of the ionic photo-products by Infra-Red Multiple Photo-Dissociation (IRMPD) spectroscopy provide unambiguous information on their structure. In addition, quantum chemical calculations allow proposing a reactive scheme and discussing it in terms of the ground-state geometry of the reactant.
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