¹³C NMR spectra of N-substituted carbazoles. Transmission of the electronic effects of substituents through the nitrogen atom to the carbazole ring

The effect of substituents attached to the nitrogen atom on the ¹³C NMR chemical shifts was determined for a series of 9-substituted carbazoles. Correlation relationships between the inductive and resonance constants of the substituents and the chemical shifts of the carbon atoms were obtained. It was shown that carbazole derivatives are similar to anilines with respect to the conductivity of electronic effects through the nitrogen atom to the carbazole ring.