ELECTRONIC SPECTRA AND STRUCTURE OF 2,4-DIHАLOPICOLINЕS AND THEIR N-OXIDES

Abstract

UV spectra of 2, 4-dihalopicolines and their N-oxides are presented, and the influence of substituents on spectral parameters is discussed. The electronic spectra were calculated by a modified INDO method. Transition energies, intensities and assignments were compared with UV spectra. The degree of intramolecular charge transfer in 2,4-dihalopicolines is greater than in 2-halopicoline N-oxides and smaller than in 2-halo-4-nitropicoline N-oxides. Difference values of HOMO-LUMO energies point out that the susceptibility on photochemical reaction lies in the order: 2-halo-4-nitro рicolinе N-oxides>2,4-dihаlopicolinе N-oxides > 2-halopicoline N-oxides > pyridine N-oxide.

How to Cite
Puszko, A. Chem. Heterocycl. Compd. 1998, 34, 1148. [Khim. Geterotsikl. Soedin. 1998, 34, 1352.]

For this article in the English edition, see DOI https://doi.org/10.1007/BF02319493