Carbon-13 nuclear magnetic resonance spectra and electronic densities of symmetrical naphthyridines

Abstract

The ¹³C n.m.r. spectra of the four symmetrical naphthyridines have been obtained and assignment of the signals performed by means of heteronuclear decoupling experiments and empirical additivity methods. The shifts were found to depend linearly upon the total charge density on the carbon atoms as calculated by self-consistent molecular orbital INDO and CNDO approximations.