Properties of Perhalopyridines

Abstract

The introduction of halogen atoms on the pyridine ring causes significant changes in its properties. Halogens reduced basicity of pyridine ring as well as dipole moment. The presence of dense halogen atoms renders a higher density of perhalopyridines than pyridine. Fluorine atoms cause a low-field shift of pyridine carbons than chlorine and bromine atoms. Perhalopyridines are mainly involved in nucleophilic substitution reactions due to the electron-withdrawing nature of halogens while perfluoropyridines are more active than others.

Keywords: 13C-NMR spectrum, 19F-NMR spectrum, Activating Effect, Addition- Elimination Mechanism, Basicity, Chemical Shifts, Density, Dipole Moment, Intermolecular Forces, IR spectrum, Meisenheimer Intermediate, Nucleophilic Substitution, Pentabromopyridine, Pentachloropyridine, Pentafluoropyridine, Raman Analysis, Shielding Effect, Spectroscopy, Steric Factors, UV-Vis Spectrum.