Abstract
Abstract The ultraviolet absorption spectra of 2-, 3- and 4-pyridine monocarboxylic acid and their N-oxides were measured in various solvents. The absorption spectra of these compounds with the exception of picolinic acid show the blue shift with the change of the solvent from dioxane to ethanol and water. The absorption band of picolinic acid occurs in the region of the shorter wavelength than that of isonicotinic acid; this fact may be caused by the formation of the intramolecular hydrogen bond, which prevents the resonance of this molecule. The absorption band of picolinic acid N-oxide occurs in the region of the shorter wevelength than that of nicotinic or isonicotinic acid N-oxide, for which the present author attributed the formation of the intramolecular hydrogen bond and the steric interaction in picolinic acid N-oxide. We also observed the n–π* absorption in picolinic acid N-oxide.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.