Related Experiment Video
Updated: Jun 23, 2026

Rapid Scan Electron Paramagnetic Resonance Opens New Avenues for Imaging Physiologically Important Parameters In Vivo
Published on: September 26, 2016
Effect of substituents on spin density in benzimidazole nitronyl nitroxide radicals studied by electron spin
Burak Esat1, Ismail Fidan, Sumeyye Bahceci
1Department of Chemistry, Fatih University, Buyukcekmece, Istanbul, Turkey. besat@fatih.edu.tr
Abstract:
Several novel benzimidazole-3-oxide-1-oxyl radicals with substituents at 5 and/or 6 position were synthesized. The ESR analysis of nitrogen hyperfine coupling constants (hfccs) revealed that substituents at 5 and 6-position affect the spin density to greater extent than substituents on the phenyl ring at 2-position. Density functional theory calculations of nitrogen hfccs were performed using several different Pople type basis sets, as well as double and triple zeta quality individual gauge for localized orbital (IGLO-II, IGLO-III) and electron paramagnetic resonance (EPR-II, EPR-II) basis sets. Experimental and theoretical hfccs are compared.
More Related Videos
Related Concept Videos
Electron Paramagnetic Resonance (EPR) Spectroscopy: Organic Radicals
NMR Spectroscopy of Benzene Derivatives
Electrophilic Aromatic Substitution: Nitration of Benzene
meta-Directing Deactivators: –NO2, –CN, –CHO, –⁠CO2R, –COR, –CO2H
Directing Effect of Substituents: ortho–para-Directing Groups
Directing Effect of Substituents: meta-Directing Groups

