Switchable intramolecular hydrogen bond in polysubstituted 5-nitrosopyrimidines

0428941 - ÚOCHB 2015 CZ eng C - Conference Paper (international conference)
Procházková, Eliška - Čechová, Lucie - Žurek, Jiří - Janeba, Zlatko - Dračínský, Martin
Switchable intramolecular hydrogen bond in polysubstituted 5-nitrosopyrimidines.
Chemistry of Nucleic Acid Components. 16th Symposium. Praha: Institute of Organic Chemistry and Biochemistry AS CR, v. v. i, 2014 - (Hocek, M.), s. 251-254. Collection Symposium Series, 14. ISBN 978-80-86241-50-0.
[Symposium on Chemistry of Nucleic Acid Components /16./. Český Krumlov (CZ), 08.06.2014-13.06.2014]
R&D Projects: GA ČR GA13-24880S
Institutional support: RVO:61388963
Keywords : intramolecular hydrogen bonds * polysubstituted 5-nitrosopyrimidines * NMR spectroscopy
Subject RIV: CC - Organic Chemistry

The formation of strong intramolecular hydrogen bonds was observed in a series of 2-amino-5-nitrosopyrimidines with alkylamino and arylamino substituents in the positions 4 and 6. Mixtures of two rotamers differing in the orientation of the nitroso group were observed in the NMR spectra of the compounds where two distinct intramolecular hydrogen bonds could be formed. In several cases, we were able to isolate and characterize the two hydrogen bond isomers (two conformers) by column chromatography. The ratio of the two rotamers in equilibrium depends strongly on the character of the substituents in the positions 4 and 6 and can be finely tuned in a broad range of conformation ratios. The experimental results were supported by DFT calculations.
Permanent Link: http://hdl.handle.net/11104/0234285