Ultraviolet Absorption Spectra of Three Isomeric Pyridine Monocarboxylic Acids and Their N-Oxides

摘要: The ultraviolet absorption spectra of 2-, 3- and 4-pyridine monocarboxylic acid their N-oxides were measured in various solvents. these compounds with the exception picolinic show blue shift change solvent from dioxane to ethanol water. band occurs region shorter wavelength than that isonicotinic acid; this fact may be caused by formation intramolecular hydrogen bond, which prevents resonance molecule. N-oxide wevelength nicotinic or N-oxide, for present author attributed bond steric interaction N-oxide. We also observed n–π*