THE ¹³С NMR, UV AND IR ABSORPTION SPECTRA OF PYRIDINEDICARBOXYLIC ACIDS

Аннотация

The ¹³С NMR, UV and IR absorption spectra of 2,3-, 2,4-, 2,5-, 2,6-, 3,4- and 3,5-pyridinedicarbохуlic acids were recorded and their spectral parameters were assigned. The influence of electronic properties of the substituents on the direction of the chemical shifts is discussed. The ultraviolet absorption spectra of the title compounds were recorded. The influence of substituents in molecule on λ_max and ε_max of spectral band are disscused. Оn the base of ¹³С NMR, UV and IR absorption spectra it was found that there is a disturbance of mutual electronic interaction of substituents by a steric ortho effect. This effect is reflected in paramagnetism of the carboxyl group, value of correlation coefficient, deformation С–О stretching bands and decrease of intensity of CT band.

Also published in Chemistry of Heterocyclic Compounds, 1999, 35 (2), pp 186-194

http://link.springer.com/article/10.1007/BF02251707