DETERMINATION OF THE <i>R</i>⇆<i>S</i> ENANTIOMERIZATION BARRIER IN 5,6-DIHYDROBENZOIMIDAZO[1,2-<i>c</i>]QUINAZOLINES

Abstract

Chiral imidazoquinazolines undergoing thermally induced reversible R⇆S enantiomerization have been synthesized by the interaction of 2-(o-aminophenyl)benzimidazoles with aldehydes and ketones. The benzimidazole fragment has been used for the first time as an indicator group in temperature-dependent ¹H NMR spectra for determining the energy barrier of this rearrangement. The effects of nearby substituents on the kinetic and activation parameters, and on the recyclization mechanism have been investigated.

Authors: P. G. Morozov and S. V. Kurbatov.

English Translation in Chemistry of Heterocyclic Compounds, 2012, 48 (5), pp 758-765

http://link.springer.com/article/10.1007/s10593-012-1054-7