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Updated: Aug 16, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Structure-NMR chemical shift relationships for novel functionalized derivatives of quinoxalines
Alsu Balandina1, Alexei Kalinin, Vakhid Mamedov
1Institute of Organic and Physical Chemistry, Arbuzov str. 8, Kazan 420008, Russia.
Abstract:
(1)H, (13)C and (15)N NMR chemical shifts for a variety of novel quinoxalines were determined by different 2D methods and were calculated using the GIAO DFT approach. Comparison with experimental data shows good correlations in the case of (1)H, (13)C and (15)N chemical shifts. Different combinations of basis sets were tested. In non-polar solvents quinoxalines exist as dimers owing to strong hydrogen bonding. Calculations for dimers improve the correlation between experiment and theory. Additive empirical methods for estimating chemical shifts have drawbacks and have to be used with a great care for this type of compound.
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