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.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 815-823, May, 2012.
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Morozov, P.G., Kurbatov, S.V. Determination of the R ⇄ S enantiomerization barrier in 5,6-dihydrobenzoimidazo[1,2-c]quinazolines. Chem Heterocycl Comp 48, 758–765 (2012). https://doi.org/10.1007/s10593-012-1054-7
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DOI: https://doi.org/10.1007/s10593-012-1054-7